This document reviews methods for measuring the thermal conductivity of liquids. It discusses why determining thermal conductivity is important for engineering applications involving heat transfer. It then describes several common techniques for measuring thermal conductivity, including steady-state parallel plate and coaxial cylinder methods as well as transient hot wire, flat plate, and 3-omega methods. For each technique, it covers the basic principles, advantages, and limitations. The focus is on developing an accurate yet simple method for measuring thermal conductivity in laboratories while minimizing the effects of convection in liquids.
This document summarizes a study on the thermal performance of a shell and tube heat exchanger using nanofluids. Finite volume modeling was used to analyze heat transfer and flow characteristics. Various nanofluids including Ag, Al2O3, CuO, SiO2, and TiO2 suspensions in water were tested and compared to pure water. The objectives were to analyze temperature profiles, heat transfer coefficients, pressure drops, and effectiveness. Results showed nanofluids had higher overall temperatures indicating more heat transfer compared to water alone. This study analyzed the potential for nanofluids to enhance heat exchanger performance.
IRJET- Experimental Investigation of Pipe in Pipe Tube Heat Exchanger using S...IRJET Journal
This document presents an experimental investigation of a pipe-in-pipe tube heat exchanger using silica (SiO2) nanofluid. The heat exchanger consists of an outer steel pipe and inner aluminum pipe. SiO2 nanofluid with 2% volume concentration and 100nm nanoparticle size is used and compared to water as the base fluid. Test results show that the nanofluid improves heat transfer characteristics and heat transfer coefficient compared to water. Specifically, the effectiveness of the heat exchanger increased by 23.1% when using nanofluid versus water. Varying the mass flow rate was also found to impact the heat transfer rate and effectiveness.
Review Paper on Experimental Analysis of Vortex TubeIRJET Journal
The document summarizes research on the experimental analysis of vortex tubes. It discusses several studies that examined how the geometric parameters and operating conditions of vortex tubes, such as nozzle diameter, tube length, inlet pressure, and cold fraction, influence the temperature separation and energy separation efficiency. Computational fluid dynamics (CFD) models are used to study the internal flow phenomena and energy separation mechanisms. The studies found that there is an optimal tube length and nozzle diameter that maximize energy separation. Increasing the inlet pressure or decreasing the cold fraction also increases the temperature difference between the cold and hot outlets.
This document presents a computational fluid dynamics (CFD) analysis of different heat sink shield profiles for electronic cooling. Three shield profiles - trapezoidal with curved inclination, trapezoidal with plane inclination, and slope shield - were modeled and simulated under a heat load of 75W. The trapezoidal shield with curved inclination achieved the lowest maximum temperature of 325.58K, highest heat transfer coefficient of 29.32, and highest surface Nusselt number of 1211.604, indicating it has the best thermal performance of the three profiles analyzed.
Differential scanning calorimetry (DSC) is a thermoanalytical technique that measures the heat flow into a sample as it is heated, cooled, or held at constant temperature. DSC curves show endothermic or exothermic reactions as peaks or dips. DSC is used to determine glass transition temperatures, crystallization and melting points, purity, and heat capacity. It has applications in pharmaceutical analysis, polymer curing processes, and general chemical analysis. DSC provides information about physical and chemical changes by measuring the difference in heat flow between the sample and reference.
Differential scanning calorimetry (DSC) is a thermal analysis technique that measures the heat flow into or out of a sample as it is heated or cooled. DSC can be used to determine properties like glass transition temperature, melting point, crystallization, heat capacity, and thermal stability. It works by heating a sample and reference pan at a controlled rate and measuring the heat differential between the two. This allows it to detect physical transformations that require or release energy like phase changes. DSC has applications in polymers, foods, pharmaceuticals, and other materials.
This document summarizes a study on the thermal performance of a shell and tube heat exchanger using nanofluids. Finite volume modeling was used to analyze heat transfer and flow characteristics. Various nanofluids including Ag, Al2O3, CuO, SiO2, and TiO2 suspensions in water were tested and compared to pure water. The objectives were to analyze temperature profiles, heat transfer coefficients, pressure drops, and effectiveness. Results showed nanofluids had higher overall temperatures indicating more heat transfer compared to water alone. This study analyzed the potential for nanofluids to enhance heat exchanger performance.
IRJET- Experimental Investigation of Pipe in Pipe Tube Heat Exchanger using S...IRJET Journal
This document presents an experimental investigation of a pipe-in-pipe tube heat exchanger using silica (SiO2) nanofluid. The heat exchanger consists of an outer steel pipe and inner aluminum pipe. SiO2 nanofluid with 2% volume concentration and 100nm nanoparticle size is used and compared to water as the base fluid. Test results show that the nanofluid improves heat transfer characteristics and heat transfer coefficient compared to water. Specifically, the effectiveness of the heat exchanger increased by 23.1% when using nanofluid versus water. Varying the mass flow rate was also found to impact the heat transfer rate and effectiveness.
Review Paper on Experimental Analysis of Vortex TubeIRJET Journal
The document summarizes research on the experimental analysis of vortex tubes. It discusses several studies that examined how the geometric parameters and operating conditions of vortex tubes, such as nozzle diameter, tube length, inlet pressure, and cold fraction, influence the temperature separation and energy separation efficiency. Computational fluid dynamics (CFD) models are used to study the internal flow phenomena and energy separation mechanisms. The studies found that there is an optimal tube length and nozzle diameter that maximize energy separation. Increasing the inlet pressure or decreasing the cold fraction also increases the temperature difference between the cold and hot outlets.
This document presents a computational fluid dynamics (CFD) analysis of different heat sink shield profiles for electronic cooling. Three shield profiles - trapezoidal with curved inclination, trapezoidal with plane inclination, and slope shield - were modeled and simulated under a heat load of 75W. The trapezoidal shield with curved inclination achieved the lowest maximum temperature of 325.58K, highest heat transfer coefficient of 29.32, and highest surface Nusselt number of 1211.604, indicating it has the best thermal performance of the three profiles analyzed.
Differential scanning calorimetry (DSC) is a thermoanalytical technique that measures the heat flow into a sample as it is heated, cooled, or held at constant temperature. DSC curves show endothermic or exothermic reactions as peaks or dips. DSC is used to determine glass transition temperatures, crystallization and melting points, purity, and heat capacity. It has applications in pharmaceutical analysis, polymer curing processes, and general chemical analysis. DSC provides information about physical and chemical changes by measuring the difference in heat flow between the sample and reference.
Differential scanning calorimetry (DSC) is a thermal analysis technique that measures the heat flow into or out of a sample as it is heated or cooled. DSC can be used to determine properties like glass transition temperature, melting point, crystallization, heat capacity, and thermal stability. It works by heating a sample and reference pan at a controlled rate and measuring the heat differential between the two. This allows it to detect physical transformations that require or release energy like phase changes. DSC has applications in polymers, foods, pharmaceuticals, and other materials.
The document discusses different methods for measuring temperature, relative humidity, and density. It describes several common temperature sensors including thermocouples, RTDs, thermistors, infrared sensors, bimetallic devices, and liquid expansion devices. It also discusses methods for measuring liquid level such as hydrostatic and bubble tube systems. Density can be measured using capacitance, hydrometers calibrated on different scales like alcoholometer and brix scales, and other methods. pH is an important process parameter that is typically measured using a pH sensor and electrode.
Experimental Investigation of Vertical Downward Flow Boiling Heat Transfer i...IJMER
The present work is carried to determine the two phase heat transfer coefficient during flowing
vertical downward in the minichannel. The minichannel test section is made up of aluminum having
hydraulic diameter 1.33mm. The experiments were carried out by varying mass flow rate from 0.1g/sec to
0.3g/sec of steam at three different vapour qualities of 0.2, 0.4 and 0.6. The result showed as the heat flux
increases there is an increase in two phase heat transfer coefficient upto 20000W/m2 0C. In addition to
that there is a decrease in treand of heat transfer coefficient for vapour quality.
Experimental Study of Heat Transfer Enhancement of Pipe-inPipe Helical Coil H...iosrjce
This document presents an experimental study of heat transfer enhancement in a pipe-in-pipe helical coil heat exchanger. Experiments were conducted with two different inner coil diameters (6mm and 8mm) under varying mass flow rates in the inner coil and annulus. The overall heat transfer coefficient and inner Nusselt number were found to increase with increasing mass flow rates. Counter-flow configuration resulted in higher heat transfer rates than parallel flow due to the larger log mean temperature difference, though overall heat transfer coefficients were similar between the two flow arrangements. Experimental results for inner Nusselt number agreed with established correlations in parallel flow but were higher in counter-flow.
IRJET- Heat Transfer Studies of Corrugated Plate Heat Exchanger using OilIRJET Journal
This document presents a study on heat transfer in corrugated plate heat exchangers using oil as the heat transfer fluid. Three corrugated plate heat exchangers with angles of 30°, 40°, and 50° were experimentally tested and compared to a flat plate heat exchanger. The heat transfer coefficient and Nusselt number increased with increasing Reynolds number and corrugation angle. The 50° corrugation angle achieved the highest heat transfer rates, representing a 40% increase over the 30° angle. Using oil as the fluid resulted in slightly higher heat transfer compared to previous studies using water. The experimental results agreed with previous CFD analyses showing improved performance of corrugated plates over flat plates.
This work deals with a study on the laminar convective heat flow of a homemade air condition ing unit through a computational fluid dynamics simulation. With adoption of chilled water as the working fluid within a tube section of the evaporative compartment of the homemade air conditioner whose radius is 5mm and Height 20mm .The numerical analysis was carried out using COMSOL MULTIPHYSICS.Simulation was carried out, using (276𝐾 (3°C) as the inlet temperature and 293𝐾 (20°C) as the outlet temperature with a flow rate of 0.15 m3 ⁄ s. The result showed the velocity profile of the working fluid and the temperature distribution before, during and after heat exchange, helping to achieve a Visual understanding of the Laminar convective fluid and heat flow phenomena within the cooling coil.
Cfd and conjugate heat transfer analysis of heat sinks with different fin geo...eSAT Journals
This document discusses a computational fluid dynamics (CFD) and conjugate heat transfer analysis of different fin geometries for heat sinks used in electronics cooling. Five fin geometries - zigzag, fluted, slanted mirror, custom pin fin, and staggered array - were analyzed under different heat loads and air velocity. The results show that the slanted mirror geometry provided the best thermal performance with the lowest thermal resistance and highest heat transfer coefficient, while maintaining a relatively low pressure drop. CFD simulations using ANSYS Fluent were conducted to analyze fluid flow, heat transfer, temperature distribution, and thermal performance of the different heat sink designs.
This document summarizes a study on the thermal analysis of circular inclined pipes subjected to natural convection using computational fluid dynamics (CFD). The study investigated the effect of parameters like tube diameter, heat supplied, and tube inclination on the temperature and heat transfer coefficient through experimental testing and CFD analysis. The experimental results were validated against CFD results, with less than 5% error found between the two. It was found that temperature increased with increasing pipe diameter and heat supply. The temperature was also strongly influenced by heat flux and diameter, and weakly dependent on tube inclination.
This document describes an experiment on heat conduction using different specimen materials and shapes. Temperature data was collected as specimens cooled in air after being heated to an initial temperature in a water bath. The results were used to calculate dimensionless temperature, Fourier number, and Biot number to determine if the lumped capacitance method could be applied. For a stainless steel sphere specimen, the method yielded a heat transfer coefficient of 32.58 W/m2K, consistent with expected values. The experiment allowed students to analyze unsteady state heat transfer and compare heat transfer coefficients for different materials.
Experimental and computational investigation of low cost standing wave thermo...IAEME Publication
This document presents experimental and computational investigation of a low-cost standing wave thermoacoustic refrigerator. Experimentally, a maximum temperature difference of 11K was obtained using a glass fiber stack with glass capillary tube spacers located at 0.15m from the speaker inlet. Computational fluid dynamics analysis using similar conditions obtained a temperature difference of 6K, in good agreement with experimental results. The study aims to develop an inexpensive standing wave thermoacoustic refrigerator design using readily available materials.
Experimental and Exergy Analysis of A Double Pipe Heat Exchanger for Parallel...IJERA Editor
This paper presents For Experimental and Exergy Analysis of a Double Pipe Heat Exchanger for Parallel- flow Arrangement. The Double pipe heat exchanger is one of the Different types of heat exchangers. double-pipe exchanger because one fluid flows inside a pipe and the other fluid flows between that pipe and another pipe that surrounds the first.In a parallel flow, both the hot and cold fluids enter the Heatexchanger at same end andmove in same direction. The present work is taken up to carry experimental work and the exergy analysis based on second law analysis of a Double-Pipe Heat Exchanger. In experimental set up hot water and cold water will be used working fluids. The inlet Hot water will be varied from 40 0C and 50 0C and cold water temperature will be varied from between 15 and 20. It has been planned to find effects of the inlet condition of both working fluid flowing through the heat exchanger on the heat transfer characteristics, entropy generation, and Exergy loss. The Mathematical modelling of heat exchanger will based on the conservation equation of mass, energy and based on second law of thermodynamics to find entropy generation and exergy losses.
A Review on Study of Heat Transfer Analysis of Helical Coil Heat Exchangersijtsrd
Now a day’s a geometrically modified Helical coil heat exchangers are widely using in industrial applications like cryogenic state processes, air conditioning, thermal nuclear reactors and waste heat recovery due to their compact size and high heat transfer coefficient. Advantage of using helical coils over straight tubes is that the residence time spread is reduced, allowing helical coils to be used to reduce axial dispersion in tubular reactors. In this study, numerical investigation of the influence of geometrical parameters such as tube diameter d , coil radius R , and coil pitch p on overall heat transfer coefficient in helical double tube heat exchangers are performed using a professional CFD software FLUENT. In recent years, numerous styles were introduced for heat exchangers that apply to completely different applications sadly, their heat transfer co efficient wasnt reliable at different operational conditions. the standard of the heat changed rate wasnt optimized and there have been many deficiencies and errors in styles. The heat transfer of the copper material is enhanced in comparison with other material unfortunately thermal resistance is reduced with an increase in pressure drop thus enhancing the heat transfer on the heat exchanger. Helical architecture is often designed with a clear motive of compact size and also address heat transfer co efficient and other ancillary attributes efficiently and effectively. So the better material is suggested for an industrial heat exchanger according to the applications is Copper with the basis of simulation results. The geometry and different dimension parameter of the helical coil show that the proposed study in different material properties and different mass flow rates to heat transfer are maximum in different parameter helical coil heat exchangers. Finally, the heat transfer increase for the copper material compared to another material but with the increase in pressure drop the corresponding thermal resistance decreases which allow the improved heat transfer rate and the rate increases from Aluminum to Bronze to Copper. With the drop in temperature, the thermal resistance is reduced which enhances the heat transfer rate. The simulation results show that the copper has a high heat transfer coefficient than Aluminum and Bronze while operating in identical conditions. Due to the extensive use of helical coils in various applications, knowledge about the flow patterns and heat transfer characteristics are important. Atul Vats | Sunil Kumar Chaturvedi | Abhishek Bhandari "A Review on Study of Heat Transfer Analysis of Helical Coil Heat Exchangers" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-4 , June 2021, URL: https://www.ijtsrd.compapers/ijtsrd43650.pdf Paper URL: https://www.ijtsrd.comengineering/mechanical-engineering/43650/a-review-on-study-of-heat-transfer-analysis-of-helical-coil-heat-exchangers/atul-vats
IRJET- Heat Transfer Enhancement of Parallel Flow and Counter Flow Heat E...IRJET Journal
This document experimentally investigates heat transfer enhancement in parallel flow and counter flow heat exchangers using different inserts, including normal twisted tape, W-cut twisted tape, right angle triangle twisted tape. Hot water at 60°C is passed through the heat exchanger at a flow rate of 2.8 kg/s. Results found that the W-cut and right angle triangle inserts produced higher heat transfer rates and coefficients compared to the normal insert, due to increased vortex generation. The counter flow configuration performed better than the parallel flow arrangement. The right angle triangle insert in the counter flow configuration produced the best performance with a heat transfer rate of 217.6kj/kg and heat transfer coefficient of 52.29 W/m2k
FLUID FLOW ANALYSIS IN AIR DUCT FLOW WITH AND WITHOUT INTERNAL THREADS USING ...IAEME Publication
Computational heat transfer flow modeling is one of the great challenges in the classical sciences. As with most problems in engineering, the interest in the heat transfer augmentation is increasing due to its extreme importance in various industrial applications. This paper deals with the analysis of heat transfer for fluid flowing through the pipe with and without internal threads using CFD. Using CFD codes for modeling the heat and fluid flow is an efficient tool for predicting equipment performance. CFD offers a convenient means to study the detailed flows and heat exchange processes, which take place inside the tube. Simulations were carried out using commercial CFD software ANSYS Fluent version 14.5. Friction factor and Nusselt number for air flowing through the specified tube (internal diameter = 0.005 m, length = 0.1 m) were obtained first for the plain tube and then for the tube with internal threads with pitch 5mm in the Reynolds number range of 2000 to 5000. Finally results will be compared to available experimental and analytical calculations. The data obtained by simulation are matching with the literature value for a plain tube with the discrepancy of less than plus or minus 5% for Nusselt number and for the friction factor.
Enhanced heat transfer for the tube with internal threads has been observed. Heat flux is more uniform all along the tube and decreases uniformly towards the center.
IRJET- Thermal Analysis of Corrugated Plate Heat Exchanger by using Ansys...IRJET Journal
This document discusses thermal analysis of a corrugated plate heat exchanger using ANSYS software through finite element analysis. It summarizes previous research on using nanofluids like Al2O3 in water to improve heat transfer in these types of heat exchangers. The document then outlines the methodology that will be used, which involves studying the corrugated plate heat exchanger with counterflow configuration and varying parameters like volume flow rate and corrugation angle to determine the optimal heat transfer results.
Thermal analysis of various duct cross sections using altair hyperworks softwaresushil Choudhary
In this work thermal analysis and comparison of various duct cross sections is done computationally using Altair
Hyperworks Software. Simple Analytical results were obtained for conduction and convection through the ducts
which can be used to build up thermal circuit. The inner surface of all ducts is maintained at constant
temperature and ambient air is at certain temperature that is less than inner surface temperature of pipe. Due to
temperature difference heat will flow from higher temperature to lower temperature. Due to temperature
difference heat will flow from higher temperature to lower temperature. The material of pipe provides
conductive resistance and air provides convective resistance. Hence this is a mix mode of heat transfer. The heat
transfer takes place in one dimension only and properties are considered to be isotropic. The ducts are assumed
to be made of aluminium having known thermal conductivity and density. The surroundings of ducts have
known convective heat transfer coefficient and temperature. The results are obtained on hyperview which are for
heat flux, temperature gradient and grid temperature. The different characteristics can be obtained by varying the
material of the ducts.
This document reviews research on the heat transfer of nanofluids when an electric or magnetic field is applied. It discusses how applied fields can affect the heat transfer performance and mechanisms of nanofluids. While studies show fields can significantly impact nanofluid heat transfer, there are differing opinions on their exact effects and mechanisms. The document aims to analyze the mechanism of thermal conductivity enhancement in nanofluids and how applied fields induce chaotic convection and heat transfer enhancement.
Evaluation of Convective Heat Transfer Coefficient of Air Flowing Through an ...Bishal Bhandari
The document evaluates the convective heat transfer coefficient of air flowing through an inclined circular duct. It describes an experimental setup used to study the effect of inclination angle and air velocity on the convective heat transfer coefficient. Tests were conducted by forcing air through a copper duct at various angles (0°, 30°, 60°, 90°, 120°, 150°) and velocities while keeping heat input constant. Temperature readings were used to calculate parameters like Reynolds number, Nusselt number, and the convective heat transfer coefficient. Results showed that the heat transfer coefficient peaks at a 90° inclination for an air velocity of 12 m/s, and is lowest at a 30° inclination for a velocity of 8.38 m/s
The document describes the monitoring instrumentation used for a helium liquefier system at the University of North Florida Physics Department. It discusses a hygrometer and purity meter that detect impurities like water moisture in stored helium gas and indicate when maintenance is needed. It also describes setting up and collaborating on a LabVIEW program to ensure proper operation of these instruments for efficient liquefaction of helium gas.
This document describes the design of a ribbed heat exchanger. It begins with an abstract that outlines heat exchangers, their uses, and the goal of designing for heat transfer rates. It then presents the problem statement of designing a ribbed heat exchanger with high effectiveness. The document calculates the required length of pipe through assumptions about temperatures and flows, using the log mean temperature difference method. The calculations find a required surface area of 3.76 square feet, which corresponds to a pipe length of 65 centimeters. In conclusion, the length of pipe for the designed heat exchanger is 65 cm based on the provided calculations.
The document describes an experimental and numerical study to enhance heat transfer on a heat exchanger using an air flow with water droplets and Al2O3/water nanofluid. The study used a test rig with an instrumented air duct to inject water droplets via nozzles toward a finned tube heat exchanger. Experiments tested different nozzle types, droplet locations, air/water flow rates and temperatures. Numerical analysis using ANSYS FLUENT modeled the governing equations to study parameter effects. Results showed maximum heat transfer enhancement of 45% occurred at a 2% nanofluid concentration with sprayed air, agreeing within 11% of experimental data.
Experimental Studies on Pool Boiling Heat Transfer Using Alumina and Graphene...IRJET Journal
This document presents an experimental study on pool boiling heat transfer using alumina and graphene oxide nanofluids. The study tested different concentrations of alumina and graphene oxide nanofluids to determine their effect on critical heat flux during pool boiling. Scanning electron microscope images showed that higher concentrations resulted in a porous nanoparticle layer forming on the heating surface, which significantly improved critical heat flux. Alumina nanofluids achieved up to 56.27% higher critical heat flux than distilled water, while graphene oxide nanofluids achieved up to 51% higher critical heat flux. The experimental results indicate that nanofluids have potential to enhance pool boiling heat transfer and critical heat flux.
Critical heat flux enhancement in pool boiling with al2 o3 water nanofluideSAT Journals
Abstract Boiling is an important phase change phenomena as it plays a crucial role in the design of high heat flux system like boilers, heat exchangers, microscopic heat transfer devices. However boiling phenomenon is limited by critical heat flux. At critical heat flux material of heated surface suffers physical damage due to lower heat transfer resulting from thin film formed over the surface. Now a days Nanofluid which is colloidal suspension of nanoparticle in base fluid is highlighted as innovative techniques to enhance critical heat flux. In the present study Al2O3 nanoparticles were characterized by using SEM and XRD analysis. From SEM images it was seen that nanoparticle has spherical morphology, and from XRD analysis average nanoparticle size determined was 29.48 nm. Five different nanofluids of concentration range from 3 gram/liter to 15 gram/liter were prepared. Critical heat flux (CHF) of each Al2O3-water nanofluid in pool boiling is determined on NiCr wire of SWG 28. The minimum critical heat flux enhancement is 30.53% at 3 gram/liter nanofluid compared to critical heat flux of distilled water. The highest critical heat flux enhancement is 72.70 % at 12 gram/liter nanofluid. Critical heat flux of nanofluid increases with increase in concentration of Al2O3 nanoparticle in distilled water up to 12 gram/liter nanofluid. Surface roughness of bare wire was 0.126 μm. Surface roughness of wire sample used in pool boiling of 3 gram/liter nanofluid is 0.299μm and highest surface roughness was 0.715 μm of heater used in pool boiling of 12 gram/liter nanofluid. The Surface roughness measurement results show the evidence of nanoparticle deposition on wire surface and its effect on Critical Heat Flux enhancement. Keywords: Critical heat flux, Nanoparticle, Nanofluid, Concentration, Surface roughness.
The document discusses different methods for measuring temperature, relative humidity, and density. It describes several common temperature sensors including thermocouples, RTDs, thermistors, infrared sensors, bimetallic devices, and liquid expansion devices. It also discusses methods for measuring liquid level such as hydrostatic and bubble tube systems. Density can be measured using capacitance, hydrometers calibrated on different scales like alcoholometer and brix scales, and other methods. pH is an important process parameter that is typically measured using a pH sensor and electrode.
Experimental Investigation of Vertical Downward Flow Boiling Heat Transfer i...IJMER
The present work is carried to determine the two phase heat transfer coefficient during flowing
vertical downward in the minichannel. The minichannel test section is made up of aluminum having
hydraulic diameter 1.33mm. The experiments were carried out by varying mass flow rate from 0.1g/sec to
0.3g/sec of steam at three different vapour qualities of 0.2, 0.4 and 0.6. The result showed as the heat flux
increases there is an increase in two phase heat transfer coefficient upto 20000W/m2 0C. In addition to
that there is a decrease in treand of heat transfer coefficient for vapour quality.
Experimental Study of Heat Transfer Enhancement of Pipe-inPipe Helical Coil H...iosrjce
This document presents an experimental study of heat transfer enhancement in a pipe-in-pipe helical coil heat exchanger. Experiments were conducted with two different inner coil diameters (6mm and 8mm) under varying mass flow rates in the inner coil and annulus. The overall heat transfer coefficient and inner Nusselt number were found to increase with increasing mass flow rates. Counter-flow configuration resulted in higher heat transfer rates than parallel flow due to the larger log mean temperature difference, though overall heat transfer coefficients were similar between the two flow arrangements. Experimental results for inner Nusselt number agreed with established correlations in parallel flow but were higher in counter-flow.
IRJET- Heat Transfer Studies of Corrugated Plate Heat Exchanger using OilIRJET Journal
This document presents a study on heat transfer in corrugated plate heat exchangers using oil as the heat transfer fluid. Three corrugated plate heat exchangers with angles of 30°, 40°, and 50° were experimentally tested and compared to a flat plate heat exchanger. The heat transfer coefficient and Nusselt number increased with increasing Reynolds number and corrugation angle. The 50° corrugation angle achieved the highest heat transfer rates, representing a 40% increase over the 30° angle. Using oil as the fluid resulted in slightly higher heat transfer compared to previous studies using water. The experimental results agreed with previous CFD analyses showing improved performance of corrugated plates over flat plates.
This work deals with a study on the laminar convective heat flow of a homemade air condition ing unit through a computational fluid dynamics simulation. With adoption of chilled water as the working fluid within a tube section of the evaporative compartment of the homemade air conditioner whose radius is 5mm and Height 20mm .The numerical analysis was carried out using COMSOL MULTIPHYSICS.Simulation was carried out, using (276𝐾 (3°C) as the inlet temperature and 293𝐾 (20°C) as the outlet temperature with a flow rate of 0.15 m3 ⁄ s. The result showed the velocity profile of the working fluid and the temperature distribution before, during and after heat exchange, helping to achieve a Visual understanding of the Laminar convective fluid and heat flow phenomena within the cooling coil.
Cfd and conjugate heat transfer analysis of heat sinks with different fin geo...eSAT Journals
This document discusses a computational fluid dynamics (CFD) and conjugate heat transfer analysis of different fin geometries for heat sinks used in electronics cooling. Five fin geometries - zigzag, fluted, slanted mirror, custom pin fin, and staggered array - were analyzed under different heat loads and air velocity. The results show that the slanted mirror geometry provided the best thermal performance with the lowest thermal resistance and highest heat transfer coefficient, while maintaining a relatively low pressure drop. CFD simulations using ANSYS Fluent were conducted to analyze fluid flow, heat transfer, temperature distribution, and thermal performance of the different heat sink designs.
This document summarizes a study on the thermal analysis of circular inclined pipes subjected to natural convection using computational fluid dynamics (CFD). The study investigated the effect of parameters like tube diameter, heat supplied, and tube inclination on the temperature and heat transfer coefficient through experimental testing and CFD analysis. The experimental results were validated against CFD results, with less than 5% error found between the two. It was found that temperature increased with increasing pipe diameter and heat supply. The temperature was also strongly influenced by heat flux and diameter, and weakly dependent on tube inclination.
This document describes an experiment on heat conduction using different specimen materials and shapes. Temperature data was collected as specimens cooled in air after being heated to an initial temperature in a water bath. The results were used to calculate dimensionless temperature, Fourier number, and Biot number to determine if the lumped capacitance method could be applied. For a stainless steel sphere specimen, the method yielded a heat transfer coefficient of 32.58 W/m2K, consistent with expected values. The experiment allowed students to analyze unsteady state heat transfer and compare heat transfer coefficients for different materials.
Experimental and computational investigation of low cost standing wave thermo...IAEME Publication
This document presents experimental and computational investigation of a low-cost standing wave thermoacoustic refrigerator. Experimentally, a maximum temperature difference of 11K was obtained using a glass fiber stack with glass capillary tube spacers located at 0.15m from the speaker inlet. Computational fluid dynamics analysis using similar conditions obtained a temperature difference of 6K, in good agreement with experimental results. The study aims to develop an inexpensive standing wave thermoacoustic refrigerator design using readily available materials.
Experimental and Exergy Analysis of A Double Pipe Heat Exchanger for Parallel...IJERA Editor
This paper presents For Experimental and Exergy Analysis of a Double Pipe Heat Exchanger for Parallel- flow Arrangement. The Double pipe heat exchanger is one of the Different types of heat exchangers. double-pipe exchanger because one fluid flows inside a pipe and the other fluid flows between that pipe and another pipe that surrounds the first.In a parallel flow, both the hot and cold fluids enter the Heatexchanger at same end andmove in same direction. The present work is taken up to carry experimental work and the exergy analysis based on second law analysis of a Double-Pipe Heat Exchanger. In experimental set up hot water and cold water will be used working fluids. The inlet Hot water will be varied from 40 0C and 50 0C and cold water temperature will be varied from between 15 and 20. It has been planned to find effects of the inlet condition of both working fluid flowing through the heat exchanger on the heat transfer characteristics, entropy generation, and Exergy loss. The Mathematical modelling of heat exchanger will based on the conservation equation of mass, energy and based on second law of thermodynamics to find entropy generation and exergy losses.
A Review on Study of Heat Transfer Analysis of Helical Coil Heat Exchangersijtsrd
Now a day’s a geometrically modified Helical coil heat exchangers are widely using in industrial applications like cryogenic state processes, air conditioning, thermal nuclear reactors and waste heat recovery due to their compact size and high heat transfer coefficient. Advantage of using helical coils over straight tubes is that the residence time spread is reduced, allowing helical coils to be used to reduce axial dispersion in tubular reactors. In this study, numerical investigation of the influence of geometrical parameters such as tube diameter d , coil radius R , and coil pitch p on overall heat transfer coefficient in helical double tube heat exchangers are performed using a professional CFD software FLUENT. In recent years, numerous styles were introduced for heat exchangers that apply to completely different applications sadly, their heat transfer co efficient wasnt reliable at different operational conditions. the standard of the heat changed rate wasnt optimized and there have been many deficiencies and errors in styles. The heat transfer of the copper material is enhanced in comparison with other material unfortunately thermal resistance is reduced with an increase in pressure drop thus enhancing the heat transfer on the heat exchanger. Helical architecture is often designed with a clear motive of compact size and also address heat transfer co efficient and other ancillary attributes efficiently and effectively. So the better material is suggested for an industrial heat exchanger according to the applications is Copper with the basis of simulation results. The geometry and different dimension parameter of the helical coil show that the proposed study in different material properties and different mass flow rates to heat transfer are maximum in different parameter helical coil heat exchangers. Finally, the heat transfer increase for the copper material compared to another material but with the increase in pressure drop the corresponding thermal resistance decreases which allow the improved heat transfer rate and the rate increases from Aluminum to Bronze to Copper. With the drop in temperature, the thermal resistance is reduced which enhances the heat transfer rate. The simulation results show that the copper has a high heat transfer coefficient than Aluminum and Bronze while operating in identical conditions. Due to the extensive use of helical coils in various applications, knowledge about the flow patterns and heat transfer characteristics are important. Atul Vats | Sunil Kumar Chaturvedi | Abhishek Bhandari "A Review on Study of Heat Transfer Analysis of Helical Coil Heat Exchangers" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-4 , June 2021, URL: https://www.ijtsrd.compapers/ijtsrd43650.pdf Paper URL: https://www.ijtsrd.comengineering/mechanical-engineering/43650/a-review-on-study-of-heat-transfer-analysis-of-helical-coil-heat-exchangers/atul-vats
IRJET- Heat Transfer Enhancement of Parallel Flow and Counter Flow Heat E...IRJET Journal
This document experimentally investigates heat transfer enhancement in parallel flow and counter flow heat exchangers using different inserts, including normal twisted tape, W-cut twisted tape, right angle triangle twisted tape. Hot water at 60°C is passed through the heat exchanger at a flow rate of 2.8 kg/s. Results found that the W-cut and right angle triangle inserts produced higher heat transfer rates and coefficients compared to the normal insert, due to increased vortex generation. The counter flow configuration performed better than the parallel flow arrangement. The right angle triangle insert in the counter flow configuration produced the best performance with a heat transfer rate of 217.6kj/kg and heat transfer coefficient of 52.29 W/m2k
FLUID FLOW ANALYSIS IN AIR DUCT FLOW WITH AND WITHOUT INTERNAL THREADS USING ...IAEME Publication
Computational heat transfer flow modeling is one of the great challenges in the classical sciences. As with most problems in engineering, the interest in the heat transfer augmentation is increasing due to its extreme importance in various industrial applications. This paper deals with the analysis of heat transfer for fluid flowing through the pipe with and without internal threads using CFD. Using CFD codes for modeling the heat and fluid flow is an efficient tool for predicting equipment performance. CFD offers a convenient means to study the detailed flows and heat exchange processes, which take place inside the tube. Simulations were carried out using commercial CFD software ANSYS Fluent version 14.5. Friction factor and Nusselt number for air flowing through the specified tube (internal diameter = 0.005 m, length = 0.1 m) were obtained first for the plain tube and then for the tube with internal threads with pitch 5mm in the Reynolds number range of 2000 to 5000. Finally results will be compared to available experimental and analytical calculations. The data obtained by simulation are matching with the literature value for a plain tube with the discrepancy of less than plus or minus 5% for Nusselt number and for the friction factor.
Enhanced heat transfer for the tube with internal threads has been observed. Heat flux is more uniform all along the tube and decreases uniformly towards the center.
IRJET- Thermal Analysis of Corrugated Plate Heat Exchanger by using Ansys...IRJET Journal
This document discusses thermal analysis of a corrugated plate heat exchanger using ANSYS software through finite element analysis. It summarizes previous research on using nanofluids like Al2O3 in water to improve heat transfer in these types of heat exchangers. The document then outlines the methodology that will be used, which involves studying the corrugated plate heat exchanger with counterflow configuration and varying parameters like volume flow rate and corrugation angle to determine the optimal heat transfer results.
Thermal analysis of various duct cross sections using altair hyperworks softwaresushil Choudhary
In this work thermal analysis and comparison of various duct cross sections is done computationally using Altair
Hyperworks Software. Simple Analytical results were obtained for conduction and convection through the ducts
which can be used to build up thermal circuit. The inner surface of all ducts is maintained at constant
temperature and ambient air is at certain temperature that is less than inner surface temperature of pipe. Due to
temperature difference heat will flow from higher temperature to lower temperature. Due to temperature
difference heat will flow from higher temperature to lower temperature. The material of pipe provides
conductive resistance and air provides convective resistance. Hence this is a mix mode of heat transfer. The heat
transfer takes place in one dimension only and properties are considered to be isotropic. The ducts are assumed
to be made of aluminium having known thermal conductivity and density. The surroundings of ducts have
known convective heat transfer coefficient and temperature. The results are obtained on hyperview which are for
heat flux, temperature gradient and grid temperature. The different characteristics can be obtained by varying the
material of the ducts.
This document reviews research on the heat transfer of nanofluids when an electric or magnetic field is applied. It discusses how applied fields can affect the heat transfer performance and mechanisms of nanofluids. While studies show fields can significantly impact nanofluid heat transfer, there are differing opinions on their exact effects and mechanisms. The document aims to analyze the mechanism of thermal conductivity enhancement in nanofluids and how applied fields induce chaotic convection and heat transfer enhancement.
Evaluation of Convective Heat Transfer Coefficient of Air Flowing Through an ...Bishal Bhandari
The document evaluates the convective heat transfer coefficient of air flowing through an inclined circular duct. It describes an experimental setup used to study the effect of inclination angle and air velocity on the convective heat transfer coefficient. Tests were conducted by forcing air through a copper duct at various angles (0°, 30°, 60°, 90°, 120°, 150°) and velocities while keeping heat input constant. Temperature readings were used to calculate parameters like Reynolds number, Nusselt number, and the convective heat transfer coefficient. Results showed that the heat transfer coefficient peaks at a 90° inclination for an air velocity of 12 m/s, and is lowest at a 30° inclination for a velocity of 8.38 m/s
The document describes the monitoring instrumentation used for a helium liquefier system at the University of North Florida Physics Department. It discusses a hygrometer and purity meter that detect impurities like water moisture in stored helium gas and indicate when maintenance is needed. It also describes setting up and collaborating on a LabVIEW program to ensure proper operation of these instruments for efficient liquefaction of helium gas.
This document describes the design of a ribbed heat exchanger. It begins with an abstract that outlines heat exchangers, their uses, and the goal of designing for heat transfer rates. It then presents the problem statement of designing a ribbed heat exchanger with high effectiveness. The document calculates the required length of pipe through assumptions about temperatures and flows, using the log mean temperature difference method. The calculations find a required surface area of 3.76 square feet, which corresponds to a pipe length of 65 centimeters. In conclusion, the length of pipe for the designed heat exchanger is 65 cm based on the provided calculations.
The document describes an experimental and numerical study to enhance heat transfer on a heat exchanger using an air flow with water droplets and Al2O3/water nanofluid. The study used a test rig with an instrumented air duct to inject water droplets via nozzles toward a finned tube heat exchanger. Experiments tested different nozzle types, droplet locations, air/water flow rates and temperatures. Numerical analysis using ANSYS FLUENT modeled the governing equations to study parameter effects. Results showed maximum heat transfer enhancement of 45% occurred at a 2% nanofluid concentration with sprayed air, agreeing within 11% of experimental data.
Experimental Studies on Pool Boiling Heat Transfer Using Alumina and Graphene...IRJET Journal
This document presents an experimental study on pool boiling heat transfer using alumina and graphene oxide nanofluids. The study tested different concentrations of alumina and graphene oxide nanofluids to determine their effect on critical heat flux during pool boiling. Scanning electron microscope images showed that higher concentrations resulted in a porous nanoparticle layer forming on the heating surface, which significantly improved critical heat flux. Alumina nanofluids achieved up to 56.27% higher critical heat flux than distilled water, while graphene oxide nanofluids achieved up to 51% higher critical heat flux. The experimental results indicate that nanofluids have potential to enhance pool boiling heat transfer and critical heat flux.
Critical heat flux enhancement in pool boiling with al2 o3 water nanofluideSAT Journals
Abstract Boiling is an important phase change phenomena as it plays a crucial role in the design of high heat flux system like boilers, heat exchangers, microscopic heat transfer devices. However boiling phenomenon is limited by critical heat flux. At critical heat flux material of heated surface suffers physical damage due to lower heat transfer resulting from thin film formed over the surface. Now a days Nanofluid which is colloidal suspension of nanoparticle in base fluid is highlighted as innovative techniques to enhance critical heat flux. In the present study Al2O3 nanoparticles were characterized by using SEM and XRD analysis. From SEM images it was seen that nanoparticle has spherical morphology, and from XRD analysis average nanoparticle size determined was 29.48 nm. Five different nanofluids of concentration range from 3 gram/liter to 15 gram/liter were prepared. Critical heat flux (CHF) of each Al2O3-water nanofluid in pool boiling is determined on NiCr wire of SWG 28. The minimum critical heat flux enhancement is 30.53% at 3 gram/liter nanofluid compared to critical heat flux of distilled water. The highest critical heat flux enhancement is 72.70 % at 12 gram/liter nanofluid. Critical heat flux of nanofluid increases with increase in concentration of Al2O3 nanoparticle in distilled water up to 12 gram/liter nanofluid. Surface roughness of bare wire was 0.126 μm. Surface roughness of wire sample used in pool boiling of 3 gram/liter nanofluid is 0.299μm and highest surface roughness was 0.715 μm of heater used in pool boiling of 12 gram/liter nanofluid. The Surface roughness measurement results show the evidence of nanoparticle deposition on wire surface and its effect on Critical Heat Flux enhancement. Keywords: Critical heat flux, Nanoparticle, Nanofluid, Concentration, Surface roughness.
IRJET- Uncertainty Analysis of Flat Plate Oscillating Heat Pipe with Differen...IRJET Journal
The document discusses the thermal performance of a flat plate oscillating heat pipe (OHP) using different working fluids. It presents the following key points:
1. An experimental setup was used to test the OHP with working fluids like water, ethanol, methanol, and acetone. Thermal resistance was calculated at varying heat input levels.
2. Acetone showed the lowest thermal resistance and best thermal performance compared to the other fluids. Thermal resistance decreased with increasing heat input for all fluids.
3. Uncertainty analysis was performed on the heating power and thermal resistance measurements. For a sample acetone test, the uncertainties were calculated to be 5.17% for heating power and 1.5%
This document summarizes an experiment on enhancing the heat transfer efficiency of a counter flow heat exchanger by using API SN oil and Super Kool Xtra oil. The experimental setup uses a copper tube heat exchanger with the hot fluid passing through the inside of the copper tube and the cold fluid passing over the outside. Temperature readings are taken at the inlet and outlet of both fluids. The results show that API SN oil provides greater heat transfer efficiency than water or Super Kool Xtra oil based on the temperature changes of the fluids. The heat exchanger has applications in industries involving heat transfer like oil/gas, power generation, and industrial processing.
CAD modeling of fluid domain with twisted tape inserts using Creo Design soft...IRJET Journal
This document summarizes a study that used computational fluid dynamics (CFD) analysis to evaluate heat transfer performance in a tube with twisted tape inserts using different working fluids. The CFD simulations modeled fluid flow and heat transfer in the tube domain using water as the base fluid and then two types of nanofluids (Al2O3/water and CuO/water) at various volume fractions and inlet velocities. Key results found that the Al2O3/water nanofluid provided the best heat transfer enhancement compared to the other fluids, with up to a 43.7% increase in heat transfer over water. The study demonstrates the effectiveness of nanofluids for improving heat transfer characteristics in pipes.
This document summarizes an experimental study on enhancing heat transfer in a corrugated plate heat exchanger by adding aluminum oxide (Al2O3) microparticles to water. The study used a 3-channel heat exchanger with sinusoidal corrugated plates at a 45 degree angle. Hot water was flowed through the central channel while water with varying concentrations of Al2O3 microparticles was flowed through the outer channels. Tested parameters included hot water inlet temperature from 40-70°C, Al2O3 volume concentration from 0-1.275%, and parallel vs counter flow configurations. Results showed adding Al2O3 microparticles increased heat exchanger effectiveness substantially, with counter flow seeing up to 0.96 effectiveness
IRJET- Double Pipe Heat Exchanger with Spiral FlowIRJET Journal
This document summarizes research on heat exchangers with parallel and counter flow configurations. It discusses how performance varies based on fluid properties and operating conditions. The document also outlines the experimental setup and procedure used to study a double pipe heat exchanger with a spiral inner tube. Tests were conducted with both parallel and counter flow arrangements to compare performance under different flow rates and inlet temperatures. Key findings from previous research on factors affecting heat transfer coefficients and effectiveness are also summarized.
1. The document discusses heat transfer through conduction in fluids and determining the thermal conductivity of water. An apparatus is used to study heat conduction in air and water without natural convection.
2. The thermal conductivity of air is known and used to calculate the heat transfer and losses in the apparatus. This allows determining the thermal conductivity of water.
3. The second part of the document discusses determining the natural convection heat transfer coefficient for a vertically oriented cylindrical tube exposed to atmospheric air and losing heat through natural convection. Different heating levels are used to study natural convection pipe flows.
IRJET-Experimental Study on Helical Tube Heat Exchanger by Varying Cross Sect...IRJET Journal
This document presents an experimental study on a helical tube heat exchanger. The study varies the cross-section of the tubes by adding nano particles like TiO2 and SiO2 to the working fluid. The performance of a helical coil heat exchanger is analyzed and compared to a straight tube heat exchanger based on parameters like log mean temperature difference (LMTD), heat transfer coefficient, and Reynolds number. The results show that a helical coil heat exchanger with nano particles added to the working fluid is more efficient, with its overall heat transfer coefficient increasing with mass flow rate.
IRJET- Comparsion of Heat Transfer Analysis of Double Pipe Heat Exchanger wit...IRJET Journal
This document describes an experimental study comparing heat transfer in a double pipe heat exchanger with and without a phase change material (PCM). Cynamide, which melts at 44°C, was used as the PCM. Hot water at 33°C and cold water at 20°C were circulated through the heat exchangers. Temperatures were recorded every 15 minutes. With the PCM, heat transfer increased when its melting temperature was reached, as the PCM absorbed heat during its phase change. The maximum heat transfer and effectiveness occurred in the setup with the PCM pipe, showing around a 20% increase in effectiveness compared to the setup without PCM. Equations for determining the heat transfer rate, maximum
CONVECTIVE HEAT TRANSFER ANALYSIS IN A HELICAL COILIRJET Journal
This document describes an experimental study of convective heat transfer in a helical coil. The study involves fabricating a setup using a copper coil submerged in a water bath inside a cylindrical tank. Thermocouples are used to measure temperatures at different positions along the coil. Experiments are conducted for different heat input levels and fluid flow rates both with and without agitation. The results are used to calculate heat transfer coefficients, Nusselt number, Reynolds number, and overall heat transfer coefficient. The aim is to better understand the heat transfer process in helical coils and determine the fluid providing maximum heat transfer.
This document discusses the design and analysis of an air-conditioned tricycle that uses thermoelectric cooling. The system uses multiple thermoelectric Peltier modules to absorb heat from the air and provide cooling. Rectangular fins and fiber sheets are used to improve heat transfer from the modules. The design is intended to provide cooling without using ozone-depleting refrigerants. Experimental results showed the thermoelectric system was able to achieve a cooling power of 50W per module with a coefficient of performance between 1.5-2. The document reviews several other studies on thermoelectric cooling systems and their advantages over traditional vapor-compression air conditioners.
IRJET- Numerical Investigation on the Heat Transfer Characteristics of Alumin...IRJET Journal
This document presents a numerical investigation of heat transfer characteristics of a double pipe heat exchanger using alumina-water nanofluid. The study examines the effects of nanoparticle concentration and volume flow rate on heat transfer coefficient, Nusselt number, pressure drop, and friction factor. It was found that adding nanoparticles significantly improved the thermal performance of the heat exchanger. The average heat transfer coefficient and Nusselt number of the base fluid increased by 26% and 12.5% respectively with a 4% nanoparticle volume concentration. Nanoparticle addition also enhanced pressure drop by around 10.11%. Heat exchanger effectiveness could be improved by approximately 16% using a 4% alumina nanoparticle concentration in the base fluid.
Hair Pin Heat Exchanger Layered with Graphene in Tube Side Using Al2O3 as Nan...IRJET Journal
This document discusses a computational fluid dynamics (CFD) analysis of a hairpin heat exchanger layered with graphene. The study aims to evaluate heat transfer performance of a hairpin heat exchanger with a graphene layer compared to one without a graphene layer. Aluminum oxide nanofluid is used as the cold fluid in the shell side. CFD simulations are performed using ANSYS Fluent to analyze heat flux, convective heat transfer coefficients, and pressure drop for both designs under varying hot fluid flow rates. Results show that the heat exchanger with graphene has higher heat flux and convective heat transfer coefficients compared to the design without graphene. Specifically, the convective heat transfer coefficient for the hot fluid reaches 1117 W
IRJET- A Review on Improvement of Heat Transfer Rate by Passive MethodsIRJET Journal
This document reviews research on improving heat transfer rates through passive methods. It discusses how adding nanoparticles to fluids to create nanofluids can improve heat transfer efficiency in heat exchangers. Several studies are summarized that found adding metal oxide nanoparticles like CuO and Al2O3 to water and ethylene glycol increased heat transfer rates compared to the base fluids alone. Corrugated plate heat exchangers in particular saw higher effectiveness with nanofluid use. However, more research is still needed to determine optimum nanoparticle concentrations for different nanofluids and applications. The aim of this review is to analyze how lower concentrations of Al2O3/water nanofluid could impact performance in plate heat exchangers.
This document summarizes an experimental study of heat transfer in a plate heat exchanger. Experiments were conducted using a three channel plate heat exchanger with hot fluid (milk or water) flowing in the central channel and cold water in the outer channels. Temperature and fluid properties were measured for parallel and counter flow arrangements. The average heat transfer coefficient was found to be 17% higher for the milk-water system compared to the water-water system in counter flow arrangement. Tables of experimental data and results including temperatures, properties, heat transfer coefficients, Nusselt numbers, and effectiveness are presented.
IRJET- An Experimental Study of Pool Boiling Heat Transfer Enhancement in...IRJET Journal
This document summarizes an experimental study on enhancing pool boiling heat transfer in deionized water using additives. The study used an experimental apparatus consisting of a glass cylinder, heating elements, and instruments to measure temperature and power. Experiments were conducted by boiling various types of water (deionized, battery, borewell) in the cylinder and measuring their critical heat flux (CHF). CHF is the highest heat flux before a vapor film forms, isolating the heating surface from the liquid. The document reviews previous studies on subcooled flow boiling and CHF models. It was found that CHF increased with the use of additives in deionized water, allowing for more efficient heat transfer and operation at higher heat fluxes
Heat transfer enhancement and friction factor analysis in tube using conical ...eSAT Journals
Abstract Role of the conical spring array for the heat transfer enhancement and pressure drop change in a pipe with constant heat flux boundary condition was investigated. Three different arrangements of conical spring array inserts were used in the experimental setup. Conical spring inserts with diverging conical spring, converging-diverging conical spring and converging conical spring array inserts arrangements were used. Water was used as a working fluid in the experimental setup. It was found that use of conical spring array inserts arrangement leads to enhancement in heat transfer. Higher heat transfer rate was achieved in the divergent spring array arrangement than the converging-diverging and converging arrangement. However, maximum friction factor is achieved in the diverging spring array insert arrangement. By increasing the Reynolds Number for different turbulator arrangement, the significant increase in Nusselt number was obtained. The enhancement in Nusselt Number for the diverging, converging-diverging, converging conical spring array arrangement was 645% ,431% and 259% respectively. The heat transfer enhancement efficiency can be evaluated based on the power consumption per unit mass of fluid. Heat transfer enhancement efficiencies were found for the divergent spring array arrangement up to 277% and for the convergent-divergent spring arrangement up to 212% and for the convergent spring array arrangement up to 153%. Keywords— Heat exchanger, Heat transfer enhancement, Friction factor, Conical spring turbulator, Heat transfer enhancement efficiency
The techniques in which some physical parameters of the systems are determined and /or recorded as a function of temperature.
DSC is a thermal technique in which differences in heat flow into a substance and a reference are measured as a function of sample temperature while the two are subjected to a controlled temperature program.
Effectiveness analysis of a thermo siphon charged with norflurane as a runnin...eSAT Journals
Abstract This work presents an investigation of the thermal performance on Thermo-siphon charged with norflurane as a running fluid,
with electro chemical nano coating. This analysis was carried out to scrutinize the optimized fill ratio and angle of inclination for
better heat transfer enhancement. The fluctuation of heat transfer ability of the thermo-siphon was analyzed for the input heat
transfer rate varies from 0 to 350 W for various filling ratios and inclination of angle. The various fill ratio of the refrigerant used
in the analysis are 70%, 60%, 50%, 40% and 30% and angle of inclination for carrying out orientation analysis were taken as 0°,
45° and 90°. Experimental results showed that the fill ratio and orientation analysis showed a better heat transfer performance on
thermo-siphon while using Norflurane as a working fluid. Experimental investigations and calculations depicted that the thermal
resistance of 50% fill ratio was found to be lower than that of other fill ratios thereby leading to a better thermal performance for
thermo-siphon charged with Norflurane. Further, upon further investigation for orientation analysis it was found that the
horizontal inclination provided better heat transfer. Hence this present investigation indicates that the thermal performance of a
thermo-siphon can be enhanced using Norflurane at an optimal fill ratio of 50% and at an angle of inclination of 0°.
Keywords: Angle of Inclination, Filling Ratio, Heat Transfer, Norflurane, Thermal Resistance,Thermo-Siphon,
Electro Chemical Nano Coating.
Similar to IRJET- Development and Calibration of Modified Parallel Plate Method for Measurement of Thermal Conductivity of Liquids: A Review (20)
TUNNELING IN HIMALAYAS WITH NATM METHOD: A SPECIAL REFERENCES TO SUNGAL TUNNE...IRJET Journal
1) The document discusses the Sungal Tunnel project in Jammu and Kashmir, India, which is being constructed using the New Austrian Tunneling Method (NATM).
2) NATM involves continuous monitoring during construction to adapt to changing ground conditions, and makes extensive use of shotcrete for temporary tunnel support.
3) The methodology section outlines the systematic geotechnical design process for tunnels according to Austrian guidelines, and describes the various steps of NATM tunnel construction including initial and secondary tunnel support.
STUDY THE EFFECT OF RESPONSE REDUCTION FACTOR ON RC FRAMED STRUCTUREIRJET Journal
This study examines the effect of response reduction factors (R factors) on reinforced concrete (RC) framed structures through nonlinear dynamic analysis. Three RC frame models with varying heights (4, 8, and 12 stories) were analyzed in ETABS software under different R factors ranging from 1 to 5. The results showed that displacement increased as the R factor decreased, indicating less linear behavior for lower R factors. Drift also decreased proportionally with increasing R factors from 1 to 5. Shear forces in the frames decreased with higher R factors. In general, R factors of 3 to 5 produced more satisfactory performance with less displacement and drift. The displacement variations between different building heights were consistent at different R factors. This study evaluated how R factors influence
A COMPARATIVE ANALYSIS OF RCC ELEMENT OF SLAB WITH STARK STEEL (HYSD STEEL) A...IRJET Journal
This study compares the use of Stark Steel and TMT Steel as reinforcement materials in a two-way reinforced concrete slab. Mechanical testing is conducted to determine the tensile strength, yield strength, and other properties of each material. A two-way slab design adhering to codes and standards is executed with both materials. The performance is analyzed in terms of deflection, stability under loads, and displacement. Cost analyses accounting for material, durability, maintenance, and life cycle costs are also conducted. The findings provide insights into the economic and structural implications of each material for reinforcement selection and recommendations on the most suitable material based on the analysis.
Effect of Camber and Angles of Attack on Airfoil CharacteristicsIRJET Journal
This document discusses a study analyzing the effect of camber, position of camber, and angle of attack on the aerodynamic characteristics of airfoils. Sixteen modified asymmetric NACA airfoils were analyzed using computational fluid dynamics (CFD) by varying the camber, camber position, and angle of attack. The results showed the relationship between these parameters and the lift coefficient, drag coefficient, and lift to drag ratio. This provides insight into how changes in airfoil geometry impact aerodynamic performance.
A Review on the Progress and Challenges of Aluminum-Based Metal Matrix Compos...IRJET Journal
This document reviews the progress and challenges of aluminum-based metal matrix composites (MMCs), focusing on their fabrication processes and applications. It discusses how various aluminum MMCs have been developed using reinforcements like borides, carbides, oxides, and nitrides to improve mechanical and wear properties. These composites have gained prominence for their lightweight, high-strength and corrosion resistance properties. The document also examines recent advancements in fabrication techniques for aluminum MMCs and their growing applications in industries such as aerospace and automotive. However, it notes that challenges remain around issues like improper mixing of reinforcements and reducing reinforcement agglomeration.
Dynamic Urban Transit Optimization: A Graph Neural Network Approach for Real-...IRJET Journal
This document discusses research on using graph neural networks (GNNs) for dynamic optimization of public transportation networks in real-time. GNNs represent transit networks as graphs with nodes as stops and edges as connections. The GNN model aims to optimize networks using real-time data on vehicle locations, arrival times, and passenger loads. This helps increase mobility, decrease traffic, and improve efficiency. The system continuously trains and infers to adapt to changing transit conditions, providing decision support tools. While research has focused on performance, more work is needed on security, socio-economic impacts, contextual generalization of models, continuous learning approaches, and effective real-time visualization.
Structural Analysis and Design of Multi-Storey Symmetric and Asymmetric Shape...IRJET Journal
This document summarizes a research project that aims to compare the structural performance of conventional slab and grid slab systems in multi-story buildings using ETABS software. The study will analyze both symmetric and asymmetric building models under various loading conditions. Parameters like deflections, moments, shears, and stresses will be examined to evaluate the structural effectiveness of each slab type. The results will provide insights into the comparative behavior of conventional and grid slabs to help engineers and architects select appropriate slab systems based on building layouts and design requirements.
A Review of “Seismic Response of RC Structures Having Plan and Vertical Irreg...IRJET Journal
This document summarizes and reviews a research paper on the seismic response of reinforced concrete (RC) structures with plan and vertical irregularities, with and without infill walls. It discusses how infill walls can improve or reduce the seismic performance of RC buildings, depending on factors like wall layout, height distribution, connection to the frame, and relative stiffness of walls and frames. The reviewed research paper analyzes the behavior of infill walls, effects of vertical irregularities, and seismic performance of high-rise structures under linear static and dynamic analysis. It studies response characteristics like story drift, deflection and shear. The document also provides literature on similar research investigating the effects of infill walls, soft stories, plan irregularities, and different
This document provides a review of machine learning techniques used in Advanced Driver Assistance Systems (ADAS). It begins with an abstract that summarizes key applications of machine learning in ADAS, including object detection, recognition, and decision-making. The introduction discusses the integration of machine learning in ADAS and how it is transforming vehicle safety. The literature review then examines several research papers on topics like lightweight deep learning models for object detection and lane detection models using image processing. It concludes by discussing challenges and opportunities in the field, such as improving algorithm robustness and adaptability.
Long Term Trend Analysis of Precipitation and Temperature for Asosa district,...IRJET Journal
The document analyzes temperature and precipitation trends in Asosa District, Benishangul Gumuz Region, Ethiopia from 1993 to 2022 based on data from the local meteorological station. The results show:
1) The average maximum and minimum annual temperatures have generally decreased over time, with maximum temperatures decreasing by a factor of -0.0341 and minimum by -0.0152.
2) Mann-Kendall tests found the decreasing temperature trends to be statistically significant for annual maximum temperatures but not for annual minimum temperatures.
3) Annual precipitation in Asosa District showed a statistically significant increasing trend.
The conclusions recommend development planners account for rising summer precipitation and declining temperatures in
P.E.B. Framed Structure Design and Analysis Using STAAD ProIRJET Journal
This document discusses the design and analysis of pre-engineered building (PEB) framed structures using STAAD Pro software. It provides an overview of PEBs, including that they are designed off-site with building trusses and beams produced in a factory. STAAD Pro is identified as a key tool for modeling, analyzing, and designing PEBs to ensure their performance and safety under various load scenarios. The document outlines modeling structural parts in STAAD Pro, evaluating structural reactions, assigning loads, and following international design codes and standards. In summary, STAAD Pro is used to design and analyze PEB framed structures to ensure safety and code compliance.
A Review on Innovative Fiber Integration for Enhanced Reinforcement of Concre...IRJET Journal
This document provides a review of research on innovative fiber integration methods for reinforcing concrete structures. It discusses studies that have explored using carbon fiber reinforced polymer (CFRP) composites with recycled plastic aggregates to develop more sustainable strengthening techniques. It also examines using ultra-high performance fiber reinforced concrete to improve shear strength in beams. Additional topics covered include the dynamic responses of FRP-strengthened beams under static and impact loads, and the performance of preloaded CFRP-strengthened fiber reinforced concrete beams. The review highlights the potential of fiber composites to enable more sustainable and resilient construction practices.
Survey Paper on Cloud-Based Secured Healthcare SystemIRJET Journal
This document summarizes a survey on securing patient healthcare data in cloud-based systems. It discusses using technologies like facial recognition, smart cards, and cloud computing combined with strong encryption to securely store patient data. The survey found that healthcare professionals believe digitizing patient records and storing them in a centralized cloud system would improve access during emergencies and enable more efficient care compared to paper-based systems. However, ensuring privacy and security of patient data is paramount as healthcare incorporates these digital technologies.
Review on studies and research on widening of existing concrete bridgesIRJET Journal
This document summarizes several studies that have been conducted on widening existing concrete bridges. It describes a study from China that examined load distribution factors for a bridge widened with composite steel-concrete girders. It also outlines challenges and solutions for widening a bridge in the UAE, including replacing bearings and stitching the new and existing structures. Additionally, it discusses two bridge widening projects in New Zealand that involved adding precast beams and stitching to connect structures. Finally, safety measures and challenges for strengthening a historic bridge in Switzerland under live traffic are presented.
React based fullstack edtech web applicationIRJET Journal
The document describes the architecture of an educational technology web application built using the MERN stack. It discusses the frontend developed with ReactJS, backend with NodeJS and ExpressJS, and MongoDB database. The frontend provides dynamic user interfaces, while the backend offers APIs for authentication, course management, and other functions. MongoDB enables flexible data storage. The architecture aims to provide a scalable, responsive platform for online learning.
A Comprehensive Review of Integrating IoT and Blockchain Technologies in the ...IRJET Journal
This paper proposes integrating Internet of Things (IoT) and blockchain technologies to help implement objectives of India's National Education Policy (NEP) in the education sector. The paper discusses how blockchain could be used for secure student data management, credential verification, and decentralized learning platforms. IoT devices could create smart classrooms, automate attendance tracking, and enable real-time monitoring. Blockchain would ensure integrity of exam processes and resource allocation, while smart contracts automate agreements. The paper argues this integration has potential to revolutionize education by making it more secure, transparent and efficient, in alignment with NEP goals. However, challenges like infrastructure needs, data privacy, and collaborative efforts are also discussed.
A REVIEW ON THE PERFORMANCE OF COCONUT FIBRE REINFORCED CONCRETE.IRJET Journal
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Optimizing Business Management Process Workflows: The Dynamic Influence of Mi...IRJET Journal
The document discusses optimizing business management processes through automation using Microsoft Power Automate and artificial intelligence. It provides an overview of Power Automate's key components and features for automating workflows across various apps and services. The document then presents several scenarios applying automation solutions to common business processes like data entry, monitoring, HR, finance, customer support, and more. It estimates the potential time and cost savings from implementing automation for each scenario. Finally, the conclusion emphasizes the transformative impact of AI and automation tools on business processes and the need for ongoing optimization.
Multistoried and Multi Bay Steel Building Frame by using Seismic DesignIRJET Journal
The document describes the seismic design of a G+5 steel building frame located in Roorkee, India according to Indian codes IS 1893-2002 and IS 800. The frame was analyzed using the equivalent static load method and response spectrum method, and its response in terms of displacements and shear forces were compared. Based on the analysis, the frame was designed as a seismic-resistant steel structure according to IS 800:2007. The software STAAD Pro was used for the analysis and design.
Cost Optimization of Construction Using Plastic Waste as a Sustainable Constr...IRJET Journal
This research paper explores using plastic waste as a sustainable and cost-effective construction material. The study focuses on manufacturing pavers and bricks using recycled plastic and partially replacing concrete with plastic alternatives. Initial results found that pavers and bricks made from recycled plastic demonstrate comparable strength and durability to traditional materials while providing environmental and cost benefits. Additionally, preliminary research indicates incorporating plastic waste as a partial concrete replacement significantly reduces construction costs without compromising structural integrity. The outcomes suggest adopting plastic waste in construction can address plastic pollution while optimizing costs, promoting more sustainable building practices.
Cricket management system ptoject report.pdfKamal Acharya
The aim of this project is to provide the complete information of the National and
International statistics. The information is available country wise and player wise. By
entering the data of eachmatch, we can get all type of reports instantly, which will be
useful to call back history of each player. Also the team performance in each match can
be obtained. We can get a report on number of matches, wins and lost.
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An In-Depth Exploration of Natural Language Processing: Evolution, Applicatio...DharmaBanothu
Natural language processing (NLP) has
recently garnered significant interest for the
computational representation and analysis of human
language. Its applications span multiple domains such
as machine translation, email spam detection,
information extraction, summarization, healthcare,
and question answering. This paper first delineates
four phases by examining various levels of NLP and
components of Natural Language Generation,
followed by a review of the history and progression of
NLP. Subsequently, we delve into the current state of
the art by presenting diverse NLP applications,
contemporary trends, and challenges. Finally, we
discuss some available datasets, models, and
evaluation metrics in NLP.
Data Communication and Computer Networks Management System Project Report.pdfKamal Acharya
Networking is a telecommunications network that allows computers to exchange data. In
computer networks, networked computing devices pass data to each other along data
connections. Data is transferred in the form of packets. The connections between nodes are
established using either cable media or wireless media.