The document summarizes the fabrication and testing of a heat exchanger test rig. Key points:
- The test rig was designed and built to study a counter-flow tube heat exchanger using aluminum sheets and tubes.
- Finite element analysis was performed on the rig design to analyze stresses. Water was heated to 40°C and pumped through one side while tap water entered the other side.
- Effectiveness-NTU method was used to calculate theoretical outlet temperatures which were compared to experimental readings to determine error percentages.
This document summarizes a research paper that analyzed heat transfer in an economizer using computational fluid dynamics (CFD). It discussed how fins can be added to economizer tubes to increase the heat transfer surface area between flue gases and boiler feedwater. The document reviewed previous research on economizer design optimization and failures. It described the working of CFD analysis using equations of continuity, momentum, and energy to model fluid flow. The study used the k-ε turbulence model in CFD software to analyze heat transfer with and without fins on an economizer.
Numerical Analysis of Heat Transfer Enhancement in Pipe-inPipe Helical Coiled...iosrjce
This document presents a numerical analysis of heat transfer enhancement in pipe-in-pipe helical coiled heat exchangers. Computational fluid dynamics (CFD) was used to analyze the effect of varying parameters like inner tube diameter, mass flow rates, and flow configuration (parallel vs. counter flow). The results show that overall heat transfer coefficients increase with increasing inner Dean number and mass flow rates. Heat transfer rates also increase with higher inner mass flow rates. Counter flow configuration provides better heat transfer than parallel flow. Increasing the inner tube size decreases the total heat transfer rate due to a reduction in annulus cross-sectional area. Measured inner Nusselt numbers agree reasonably well with existing correlations.
Heat exchangers are used widely in industrial application such as chemical,
food processing, power production, refrigeration and air-conditioning
industries. Helical coiled heat exchangers are used in order to obtain a large
heat transfer per unit volume and to enhance the heat transfer rate on the inside
surface. In the present study, CFD simulations are carried out for a counter
flow tube in tube helical heat exchanger where hot water flows through the
inner tube and cold water flows through the outer tube. From the simulation
results heat transfer coefficient, pressure drop and nusselt number are
calculated. The heat transfer characteristics of the same are compared with that
of a counter flow tube in tube straight tube heat exchanger of same length
under same temperature and flow conditions. CFD simulation results showed
that the helical tube in tube heat exchanger is more effective than the straight
tube in tube heat exchanger.
Experimental Investigation of a Helical Coil Heat Exchangerinventy
The document summarizes an experimental study comparing the performance of a helical coil heat exchanger to a straight tube heat exchanger. Researchers designed, fabricated, and tested both types of heat exchangers. Results showed that the helical coil design had higher heat transfer rates, effectiveness, and overall heat transfer coefficients than the straight tube design across all flow rates and operating conditions. This is because the coiled tube shape induces secondary fluid flows that enhance mixing and heat transfer compared to the straight tube. The study concludes that helical coil heat exchangers have better performance than straight tube designs for industrial heat exchange applications.
Optimization of a Shell and Tube Condenser using Numerical MethodIJERA Editor
The purpose of this study was to investigate the effect of installation of the tube external surfaces, their parameter and variable in a shell-and-tube condenser. Variation of heat transfer coefficient with each variable of shell and tube condenser was measured each test. The optimization tube outside diameter size was analyzed and use extended surface area attached tube with tube material and tube layout and arrangement (Number of tube a triangular or hexagonal arrangement) on shell-and tube condenser. The computer programming was used to get faster output in less time. Results suggest that mean heat transfer coefficient in variable condition were mainly at velocity is fixed. And also average additional surfaces and tube layout and the arrangement comparison with the quantity of the heat transfer.
1) The document analyzes heat transfer in a double pipe heat exchanger with helical tape inserts in the annulus of the inner pipe using computational fluid dynamics (CFD).
2) A 3D model is developed and simulations are run using the SST k-ω turbulent model to analyze how helical tape inserts influence heat transfer and pressure drop at different pitch lengths and Reynolds numbers.
3) The results show that helical tape inserts increase the heat transfer rate but also increase pressure drop due to flow disruption. Nusselt number and friction factor are found to correlate well with Reynolds number for enhancing heat transfer.
Esign and thermal evaluation of shell and helical coil heat exchangereSAT Journals
Abstract
Heat exchangers are the important engineering equipments used for transferring heat from one fluid to another. Heat exchangers are widely used in various kinds of application such as power plants, nuclear reactors, refrigeration and air-conditioning systems, heat recovery systems, petrochemical, mechanical, biomedical industries. Helical coil heat exchangers are gaining wide importance now-a-days because it can give high heat transfer coefficient in small footprint of surface area. This paper focuses on the designing of shell and helical coil heat exchanger and its thermal evaluation with counter flow configuration. The thermal analysis is carried out considering the various parameters such as flow rate of cold water, flow rate of hot water, temperature, effectiveness and overall heat transfer coefficient.
Keywords— Helical coil heat exchanger, Counter flow, Flow rate, effectiveness, heat transfer coefficient etc.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
This document summarizes a research paper that analyzed heat transfer in an economizer using computational fluid dynamics (CFD). It discussed how fins can be added to economizer tubes to increase the heat transfer surface area between flue gases and boiler feedwater. The document reviewed previous research on economizer design optimization and failures. It described the working of CFD analysis using equations of continuity, momentum, and energy to model fluid flow. The study used the k-ε turbulence model in CFD software to analyze heat transfer with and without fins on an economizer.
Numerical Analysis of Heat Transfer Enhancement in Pipe-inPipe Helical Coiled...iosrjce
This document presents a numerical analysis of heat transfer enhancement in pipe-in-pipe helical coiled heat exchangers. Computational fluid dynamics (CFD) was used to analyze the effect of varying parameters like inner tube diameter, mass flow rates, and flow configuration (parallel vs. counter flow). The results show that overall heat transfer coefficients increase with increasing inner Dean number and mass flow rates. Heat transfer rates also increase with higher inner mass flow rates. Counter flow configuration provides better heat transfer than parallel flow. Increasing the inner tube size decreases the total heat transfer rate due to a reduction in annulus cross-sectional area. Measured inner Nusselt numbers agree reasonably well with existing correlations.
Heat exchangers are used widely in industrial application such as chemical,
food processing, power production, refrigeration and air-conditioning
industries. Helical coiled heat exchangers are used in order to obtain a large
heat transfer per unit volume and to enhance the heat transfer rate on the inside
surface. In the present study, CFD simulations are carried out for a counter
flow tube in tube helical heat exchanger where hot water flows through the
inner tube and cold water flows through the outer tube. From the simulation
results heat transfer coefficient, pressure drop and nusselt number are
calculated. The heat transfer characteristics of the same are compared with that
of a counter flow tube in tube straight tube heat exchanger of same length
under same temperature and flow conditions. CFD simulation results showed
that the helical tube in tube heat exchanger is more effective than the straight
tube in tube heat exchanger.
Experimental Investigation of a Helical Coil Heat Exchangerinventy
The document summarizes an experimental study comparing the performance of a helical coil heat exchanger to a straight tube heat exchanger. Researchers designed, fabricated, and tested both types of heat exchangers. Results showed that the helical coil design had higher heat transfer rates, effectiveness, and overall heat transfer coefficients than the straight tube design across all flow rates and operating conditions. This is because the coiled tube shape induces secondary fluid flows that enhance mixing and heat transfer compared to the straight tube. The study concludes that helical coil heat exchangers have better performance than straight tube designs for industrial heat exchange applications.
Optimization of a Shell and Tube Condenser using Numerical MethodIJERA Editor
The purpose of this study was to investigate the effect of installation of the tube external surfaces, their parameter and variable in a shell-and-tube condenser. Variation of heat transfer coefficient with each variable of shell and tube condenser was measured each test. The optimization tube outside diameter size was analyzed and use extended surface area attached tube with tube material and tube layout and arrangement (Number of tube a triangular or hexagonal arrangement) on shell-and tube condenser. The computer programming was used to get faster output in less time. Results suggest that mean heat transfer coefficient in variable condition were mainly at velocity is fixed. And also average additional surfaces and tube layout and the arrangement comparison with the quantity of the heat transfer.
1) The document analyzes heat transfer in a double pipe heat exchanger with helical tape inserts in the annulus of the inner pipe using computational fluid dynamics (CFD).
2) A 3D model is developed and simulations are run using the SST k-ω turbulent model to analyze how helical tape inserts influence heat transfer and pressure drop at different pitch lengths and Reynolds numbers.
3) The results show that helical tape inserts increase the heat transfer rate but also increase pressure drop due to flow disruption. Nusselt number and friction factor are found to correlate well with Reynolds number for enhancing heat transfer.
Esign and thermal evaluation of shell and helical coil heat exchangereSAT Journals
Abstract
Heat exchangers are the important engineering equipments used for transferring heat from one fluid to another. Heat exchangers are widely used in various kinds of application such as power plants, nuclear reactors, refrigeration and air-conditioning systems, heat recovery systems, petrochemical, mechanical, biomedical industries. Helical coil heat exchangers are gaining wide importance now-a-days because it can give high heat transfer coefficient in small footprint of surface area. This paper focuses on the designing of shell and helical coil heat exchanger and its thermal evaluation with counter flow configuration. The thermal analysis is carried out considering the various parameters such as flow rate of cold water, flow rate of hot water, temperature, effectiveness and overall heat transfer coefficient.
Keywords— Helical coil heat exchanger, Counter flow, Flow rate, effectiveness, heat transfer coefficient etc.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Effect of nanofluids and mass flow rate of air on heat transfer rate in autom...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Helically Coiled Tube with Different Geometry and Curvature Ratio on Convecti...AM Publications
A helically coil-tube heat exchanger is generally applied in industry applications due to its compact structure, larger heat transfer area and higher heat transfer capability. Several studies from literature have also indicated that heat transfer rate in helically coiled tube are superior to straight tube due to complex flow pattern exist inside helical pipe. The concept behind compact heat exchanger is to decrease size and increase heat load which is the typical feature of modern helical tube heat exchanger. While the heat transfer characteristics of helical coil heat exchangers are available in the literature, This paper elaborates a brief review on different curvature ratio and geometry of tubes in heat transfer through heat exchangers.
Analysis of Coiled-Tube Heat Exchangers to Improve Heat Transfer Rate With Sp...IJMER
Steady heat transfer enhancement has been studied in helically coiled-tube heat exchangers. The outer side of the wall of the heat exchanger contains a helical corrugation which makes a helical rib on the inner side of the tube wall to induce additional swirling motion of fluid particles. Numerical calculations have been carried out to examine different geometrical parameters and the impact of flow and thermal boundary conditions for the heat transfer rate in laminar and transitional flow regimes. Calculated results have been compared to existing empirical formula and experimental tests to investigate the validity of the numerical results in case of common helical tube heat exchanger and additionally results of the numerical computation of corrugated straight tubes for laminar and transition flow have been validated with experimental tests available in the literature. Comparison of the flow and temperature fields in case of common helical tube and the coil with spirally corrugated wall configuration are discussed. Heat exchanger coils with helically corrugated wall configuration show 80–100% increase for the inner side heat transfer rate due to the additionally developed swirling motion while the relative pressure drop is 10–600% larger compared to the common helically coiled heat exchangers. New empirical Co-relation has been proposed for the fully developed inner side heat transfer prediction in case of helically corrugated wall configuration.
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.
The document presents information on helical baffle heat exchangers. It begins with introducing heat exchangers and defining a helical baffle heat exchanger. It then discusses the design of helixchangers, including thermal analysis of the helical baffles and tube side as well as hydrodynamic analysis of the shell side. Overall heat transfer coefficient is also examined. Key advantages of helixchangers are reduced bypass effects, fouling, vibration, and maintenance compared to traditional shell and tube exchangers. Future areas of research include CFD optimization and analysis of flow patterns and velocities.
This document discusses heat exchanger networks and energy recovery in industrial processes. It begins with an overview of topics like energy balances, pinch technology, and differential energy balances. It then covers specific techniques for energy recovery such as heat exchange, waste heat boilers, heat pumps, and using combustible wastes as fuels. Key concepts discussed include minimizing heat transfer across the pinch point, not using utilities below the pinch, and designing networks to maximize energy recovery and minimize utility usage.
Experimental investigation of performance of plate heat exchanger for water a...eSAT Journals
Abstract
Compact heat exchangers are most widely used for heat transfer applications in industries. Plate heat exchanger is one such compact heat exchanger, provides more area for heat transfer between two fluids in comparison with shell and tube heat exchanger. Plate type heat exchangers are widely used for liquid-to-liquid heat transfer applications with high density working fluids. This study is focused on use of plate type heat exchanger for water as a working fluid. This research work deals with experimental investigation of plate type heat exchanger with evaluation of convective heat transfer coefficient, overall heat transfer coefficient, exchanger effectiveness. The heat exchanger used for carrying out this work consists of thin metal welded plates of stainless steel with 1mm thickness, rectangular geometry and distance between two plates is 7mm. This test setup consists of total 16 numbers of plates and it is designed to withstand with 850C temperature, pressure drop is neglected. Tests are conducted by varying operating parameters like mass flow rate, inlet temperatures of hot water. The main objective of this work is to find effects of these parameters on performance of plate heat exchanger with parallel flow arrangement. Results show that, overall heat transfer coefficient and convective heat transfer coefficient increases with increase in mass flow rate and Reynolds number. Also the effectiveness varies slightly with heat capacity ratio. In this study, maximum effectiveness achieved for plate heat exchanger with water as a working fluid is 0.48.Use of plate heat exchanger is more advantageous than the tube type heat exchanger with same effectiveness, as it occupies less space.
Keywords: Plate heat exchanger, Convective heat transfer coefficient, Effectiveness, Overall heat transfer coefficient, Reynolds number.
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
This document provides a theoretical investigation of a solar energy driven combined power and refrigeration cycle that uses oil as the heat transfer medium. The cycle integrates a Rankine cycle for power production and an ejector refrigeration cycle for cold production. Thermodynamic analyses of the cycle were conducted to determine first law efficiency of 20% and second law efficiency of 11%. Key cycle components include a heliostat field, central receiver, heat recovery steam generator, turbine, evaporator, condenser and ejector. Effects of parameters such as steam temperature and evaporator temperature on cycle performance were examined.
IRJET- CFD Analysis of Double Pipe Heat Exchanger with Different Inner Se...IRJET Journal
This document analyzes the heat transfer performance of a double pipe heat exchanger with circular and square inner sections using computational fluid dynamics (CFD). CFD simulations were conducted using ANSYS Fluent to analyze temperature contours and heat transfer rates. The results showed that the square inner section heat exchanger absorbed more heat from the hot fluid and had a higher heat flow rate than the circular section design, with the cold fluid outlet temperature being higher for the square section. In conclusion, the square inner section design exhibited better heat transfer performance compared to the conventional circular section design for this type of heat exchanger.
A REVIEW PAPER ON ANALYSIS OF AUTOMOBILE RADIATORijsrd.com
An Automotive engine cooling system takes out of excess heat produced during engine operation. An automobile cooling system regulates engine surface temperature for engine optimum efficiency. Recent advancement and development in engine for power forced engine cooling system to develop new strategies to improve its performance efficiency. Also to reduce fuel consumption along with controlling engine emission to mitigate environmental pollution norms. This paper throws light on parameters which influence radiator performance along with reviews some of the conventional and modern approaches to enhance radiator performance. This review paper Focus on the various research papers regarding experimental, CFD and Numerical analysis to improving automobile radiator efficiency.
CFD Simulation and Heat Transfer Analysis of Automobile Radiator using Helica...IJERD Editor
To ensure smooth running of an automotive vehicle under any variable load conditions, one of the major systems necessary is the cooling system. Automobile radiators are becoming highly power-packed with increasing power to weight or volume ratio. Computational Fluid Dynamics (CFD) is one of the important software tools to access preliminary design and the performance of the radiator. In this paper, a 55 hp engine radiator data is taken for analysis in CFD. The model is done Pro-E software and imported in ANSYS-12. Helical tubes are considered for the radiator with two different pitches like 15mm & 20mm. The comparison is done for different mass flow rates like 2.3, 2.0, 1.0, 0.5 kg/sec in helical type tubes. It is found that there is more heat dissipation rate in 15mm pitch helical tubes compared to 20mm pitch helical tubes. Maximum temperature drop & minimum pressure drop occurs in case of 0.5 kg/sec of mass flow rate. It is observed that with increased mass flow rate, there is decrease in temperature drop & increase in pressure drop
Design and Thermal Analysis of Hydraulic Oil Cooler by using Computational Fl...IRJET Journal
This document describes a study analyzing the thermal performance of a hydraulic oil cooler using computational fluid dynamics (CFD). It involves:
1) Designing a hydraulic oil cooler with cross-flow heat exchanger cores to transfer heat from hot hydraulic oil into ambient air.
2) Developing a thermal model and equations to calculate heat transfer rates, oil/air temperatures, heat transfer coefficients, and surface area required.
3) Validating the model through experimental testing of an oil cooler setup and comparing predicted vs actual temperature values.
This document presents a parametric study on automotive radiators. It discusses the importance of cooling engines and describes the types and geometry of radiators. It then examines the effects of varying air and coolant mass flow, air inlet temperature, coolant type, fin pitch, louver angle, and coolant flow layout on the radiator's performance. The studies show that heat transfer and cooling capacity increase with higher air and coolant flows. Coolant type, fin pitch, louver angle, and flow layout also impact radiator efficiency. The document concludes that parametric studies help design high performance radiators and that heat exchange depends on temperature gradients between the radiator and inlet air.
Comparative Study of ECONOMISER Using the CFD Analysis IJMER
This paper presents a simulation of the economizer zone, which allowsstudying the flow
patterns developed in the fluid, while it flows along the length of the economizer. The past failure
details revelsthat erosion is more in U-bend areas of Economizer Unit because of increase in flue gas
velocity near these bends. But it isobserved that the velocity of flue gases surprisingly increases near
the lower bends as compared to upper ones. The model issolved using conventional CFD techniques by
FLUENT software. In which the individual tubes are treated as sub-gridfeatures. A geometrical model
is used to describe the multiplicity of heat-exchanging structures and the interconnectionsamong them.
The Computational Fluid Dynamics (CFD) approach is utilised for the creation of a three-dimensional
modelof the economizer coil of single column tube. With equilibrium assumption applied for
description of the system chemistry. The flue gastemperature, pressure and velocity field of fluid flow
within an economizer tube using the actual bounda
The objective of this experiment is to calculate the rate of the heat transfer log mean temperature difference, and the overall heat transfer coefficient in case of Counter flow
This document describes a heat exchanger design project. It provides theory on heat exchanger design including heat transfer rate calculations. It then details the CFD simulation process used to model and analyze different heat exchanger designs. This included an initial 2D model, mesh refinement studies to determine optimal mesh size, and modeling variations in pipe spacing, flow direction, and a 3D design. Results were analyzed using temperature, turbulence, and velocity contours to evaluate design performance.
Modeling and Fluid Flow Analysis of Wavy Fin Based Automotive RadiatorIJERA Editor
In continuous technological development, an automotive industry has increased the demand for high efficiency engines. A high efficiency engines in not only based on its performance but also for better fuel economy and less emission rate. Radiator is one of the important parts of the internal combustion engine cooling system. The manufacturing cost of the radiator is 20 percent of the whole cost of the engine. So improving the performance and reducing cost of radiators are necessary research. For higher cooling capacity of radiator, addition of fins is one of the approaches to increase the cooling rate of the radiator. In addition, heat transfer fluids at air and fluid side such as water and ethylene glycol exhibit very low thermal conductivity. As a result there is a need for new and innovative heat transfer fluids, known as “Nano fluid” for improving heat transfer rate in an automotive radiator. Recently there have been considerable research findings highlighting superior heat transfer performances of nanofluids about 15-25% of heat transfer enhancement can be achieved by using types of nanofluids. With these specific characteristics, the size and weight of an automotive car radiator can be reduced without affecting its heat transfer performance. An automotive radiator (Wavy fin type) model is modeled on modeling software CATIA V5 and performance evaluation is done on pre-processing software ANSYS 14.0. The temperature and velocity distribution of coolant and air are analyzed by using Computational fluid dynamics environment software CFX. Results have shown that the rate of heat transfer is better when nano fluid (Si C + water) is used as coolant, than the conventional coolant.
45
50
55
60
65
Pr (ata)
Graph 3. Variation of power and efficiency with pressure at temperature at 4500C
This document summarizes the results of a sensitivity analysis performed on a heat recovery steam generator (HRSG) for a GE 6FA gas turbine combined cycle power plant. The analysis varied the steam pressure from 40 to 62 atmospheres and steam temperature from 400 to 500 degrees Celsius to determine the optimal operating point. The maximum power and efficiency were achieved at different pressure-temperature combinations, with 58 atmospheres generally providing the best results for temperatures between 450-500 degrees Celsius. Graphs show the relationships between pressure, power, efficiency
Analysis of Double Pipe Heat Exchanger With Helical FinsIRJET Journal
This document analyzes a double pipe heat exchanger with helical fins through computational fluid dynamics (CFD). It aims to study the flow and temperature fields inside the tubes for different helical fin angles. The geometry of the double pipe heat exchanger is modeled in CATIA V5 and meshed in Hypermesh. CFD simulations are performed in ANSYS Fluent to analyze the flow and temperature distributions for fin angles of 0, 5, 10, 15, 20, and 25 degrees. The results determine that heat transfer rate and overall heat transfer coefficient increase with helical fins compared to a smooth tube, with fins providing additional surface area to enhance heat transfer.
Shell & tube heat exchanger single fluid flow heat transferVikram Sharma
This article was produced to highlight the fundamentals of single-phase heat exchanger rating using Kern's method. The content is strictly academic with no reference to industrial best practices.
Effect of nanofluids and mass flow rate of air on heat transfer rate in autom...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Helically Coiled Tube with Different Geometry and Curvature Ratio on Convecti...AM Publications
A helically coil-tube heat exchanger is generally applied in industry applications due to its compact structure, larger heat transfer area and higher heat transfer capability. Several studies from literature have also indicated that heat transfer rate in helically coiled tube are superior to straight tube due to complex flow pattern exist inside helical pipe. The concept behind compact heat exchanger is to decrease size and increase heat load which is the typical feature of modern helical tube heat exchanger. While the heat transfer characteristics of helical coil heat exchangers are available in the literature, This paper elaborates a brief review on different curvature ratio and geometry of tubes in heat transfer through heat exchangers.
Analysis of Coiled-Tube Heat Exchangers to Improve Heat Transfer Rate With Sp...IJMER
Steady heat transfer enhancement has been studied in helically coiled-tube heat exchangers. The outer side of the wall of the heat exchanger contains a helical corrugation which makes a helical rib on the inner side of the tube wall to induce additional swirling motion of fluid particles. Numerical calculations have been carried out to examine different geometrical parameters and the impact of flow and thermal boundary conditions for the heat transfer rate in laminar and transitional flow regimes. Calculated results have been compared to existing empirical formula and experimental tests to investigate the validity of the numerical results in case of common helical tube heat exchanger and additionally results of the numerical computation of corrugated straight tubes for laminar and transition flow have been validated with experimental tests available in the literature. Comparison of the flow and temperature fields in case of common helical tube and the coil with spirally corrugated wall configuration are discussed. Heat exchanger coils with helically corrugated wall configuration show 80–100% increase for the inner side heat transfer rate due to the additionally developed swirling motion while the relative pressure drop is 10–600% larger compared to the common helically coiled heat exchangers. New empirical Co-relation has been proposed for the fully developed inner side heat transfer prediction in case of helically corrugated wall configuration.
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.
The document presents information on helical baffle heat exchangers. It begins with introducing heat exchangers and defining a helical baffle heat exchanger. It then discusses the design of helixchangers, including thermal analysis of the helical baffles and tube side as well as hydrodynamic analysis of the shell side. Overall heat transfer coefficient is also examined. Key advantages of helixchangers are reduced bypass effects, fouling, vibration, and maintenance compared to traditional shell and tube exchangers. Future areas of research include CFD optimization and analysis of flow patterns and velocities.
This document discusses heat exchanger networks and energy recovery in industrial processes. It begins with an overview of topics like energy balances, pinch technology, and differential energy balances. It then covers specific techniques for energy recovery such as heat exchange, waste heat boilers, heat pumps, and using combustible wastes as fuels. Key concepts discussed include minimizing heat transfer across the pinch point, not using utilities below the pinch, and designing networks to maximize energy recovery and minimize utility usage.
Experimental investigation of performance of plate heat exchanger for water a...eSAT Journals
Abstract
Compact heat exchangers are most widely used for heat transfer applications in industries. Plate heat exchanger is one such compact heat exchanger, provides more area for heat transfer between two fluids in comparison with shell and tube heat exchanger. Plate type heat exchangers are widely used for liquid-to-liquid heat transfer applications with high density working fluids. This study is focused on use of plate type heat exchanger for water as a working fluid. This research work deals with experimental investigation of plate type heat exchanger with evaluation of convective heat transfer coefficient, overall heat transfer coefficient, exchanger effectiveness. The heat exchanger used for carrying out this work consists of thin metal welded plates of stainless steel with 1mm thickness, rectangular geometry and distance between two plates is 7mm. This test setup consists of total 16 numbers of plates and it is designed to withstand with 850C temperature, pressure drop is neglected. Tests are conducted by varying operating parameters like mass flow rate, inlet temperatures of hot water. The main objective of this work is to find effects of these parameters on performance of plate heat exchanger with parallel flow arrangement. Results show that, overall heat transfer coefficient and convective heat transfer coefficient increases with increase in mass flow rate and Reynolds number. Also the effectiveness varies slightly with heat capacity ratio. In this study, maximum effectiveness achieved for plate heat exchanger with water as a working fluid is 0.48.Use of plate heat exchanger is more advantageous than the tube type heat exchanger with same effectiveness, as it occupies less space.
Keywords: Plate heat exchanger, Convective heat transfer coefficient, Effectiveness, Overall heat transfer coefficient, Reynolds number.
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
This document provides a theoretical investigation of a solar energy driven combined power and refrigeration cycle that uses oil as the heat transfer medium. The cycle integrates a Rankine cycle for power production and an ejector refrigeration cycle for cold production. Thermodynamic analyses of the cycle were conducted to determine first law efficiency of 20% and second law efficiency of 11%. Key cycle components include a heliostat field, central receiver, heat recovery steam generator, turbine, evaporator, condenser and ejector. Effects of parameters such as steam temperature and evaporator temperature on cycle performance were examined.
IRJET- CFD Analysis of Double Pipe Heat Exchanger with Different Inner Se...IRJET Journal
This document analyzes the heat transfer performance of a double pipe heat exchanger with circular and square inner sections using computational fluid dynamics (CFD). CFD simulations were conducted using ANSYS Fluent to analyze temperature contours and heat transfer rates. The results showed that the square inner section heat exchanger absorbed more heat from the hot fluid and had a higher heat flow rate than the circular section design, with the cold fluid outlet temperature being higher for the square section. In conclusion, the square inner section design exhibited better heat transfer performance compared to the conventional circular section design for this type of heat exchanger.
A REVIEW PAPER ON ANALYSIS OF AUTOMOBILE RADIATORijsrd.com
An Automotive engine cooling system takes out of excess heat produced during engine operation. An automobile cooling system regulates engine surface temperature for engine optimum efficiency. Recent advancement and development in engine for power forced engine cooling system to develop new strategies to improve its performance efficiency. Also to reduce fuel consumption along with controlling engine emission to mitigate environmental pollution norms. This paper throws light on parameters which influence radiator performance along with reviews some of the conventional and modern approaches to enhance radiator performance. This review paper Focus on the various research papers regarding experimental, CFD and Numerical analysis to improving automobile radiator efficiency.
CFD Simulation and Heat Transfer Analysis of Automobile Radiator using Helica...IJERD Editor
To ensure smooth running of an automotive vehicle under any variable load conditions, one of the major systems necessary is the cooling system. Automobile radiators are becoming highly power-packed with increasing power to weight or volume ratio. Computational Fluid Dynamics (CFD) is one of the important software tools to access preliminary design and the performance of the radiator. In this paper, a 55 hp engine radiator data is taken for analysis in CFD. The model is done Pro-E software and imported in ANSYS-12. Helical tubes are considered for the radiator with two different pitches like 15mm & 20mm. The comparison is done for different mass flow rates like 2.3, 2.0, 1.0, 0.5 kg/sec in helical type tubes. It is found that there is more heat dissipation rate in 15mm pitch helical tubes compared to 20mm pitch helical tubes. Maximum temperature drop & minimum pressure drop occurs in case of 0.5 kg/sec of mass flow rate. It is observed that with increased mass flow rate, there is decrease in temperature drop & increase in pressure drop
Design and Thermal Analysis of Hydraulic Oil Cooler by using Computational Fl...IRJET Journal
This document describes a study analyzing the thermal performance of a hydraulic oil cooler using computational fluid dynamics (CFD). It involves:
1) Designing a hydraulic oil cooler with cross-flow heat exchanger cores to transfer heat from hot hydraulic oil into ambient air.
2) Developing a thermal model and equations to calculate heat transfer rates, oil/air temperatures, heat transfer coefficients, and surface area required.
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REPORT-MSD
1. The Fabrication and Testing of Heat Exchanger Experimental Test Rig
M. H. Rahman*, S. Z. Zahrin, N. Z. Kolan, M. A. Yusuff and A. B. A. Rahim
Faculty of Mechanical Engineering,
Universiti Malaysia Pahang,
26600 Pekan, Pahang, Malaysia.
*Email: mohdhelmyrahman92@gmail.com
Phone: +60183793352
ABSTRACT
This project focuses on designing and fabricating a heat exchanger test rig using a
designed tube counter flow heat exchanger. Aluminium sheet metal is used to fabricate a tank
to be filled with water as medium. Finite Element Analysis (FEA) is also done to the table
design in order to analyse the stress develop by actual weight experienced during the process.
The water in the tank will be heated by a heater to a temperature around 40°C to and a water
pump is used to produce a hot channel flow for the system. Tap water is used as the cold
channel for the heat exchanger system with inlet temperature around 29°C connected to the
system by a hose. The effectiveness-NTU method is used to calculate the theoretical hot
channel outlet value of the heat exchanger design and the heat transfer rate for the system.
The experimental temperature value obtained by thermocouple reading will be used to
calculate the percentage error between the experimental and theoretical values.
Keywords: Counter-flow tube heat exchanger; effectiveness-NTU method; heat transfer rate
2. INTRODUCTION
A heat exchanger is a piece of equipment built for efficient heat transfer from one
medium to another. The media may be separated by a solid wall to prevent mixing or they
may be in direct contact. They are widely used in space heating, refrigeration, air
conditioning, power plants, chemical plants, petrochemical plants, petroleum refineries,
natural gas processing, and sewage treatment. The classic example of a heat exchanger is
found in an internal combustion engine in which a circulating fluid known as engine coolant
flows through radiator coils and air flows past the coils, which cools the coolant and heats the
incoming air. Examples in practice in which flowing fluids exchange heat are air intercoolers
and preheaters, condensers and boilers in steam plant, condensers and evaporators in
refrigerator units, and many other industrial processes in which a liquid or gas is required to
be either cooled or heated (Eckert and Drakes, 1987).
In heat exchanger design, there are three types of flow arrangements; counter-flow,
parallel-flow, and cross-flow. In the counter-flow heat exchanger, both fluids entered the
exchanger from opposite sides. In the parallel-flow heat exchanger the fluids come in from
the same end and move parallel to each other as they flow to the other side. The crossflow
heat exchanger moves the fluids in a perpendicular fashion. Compare to other flow
arrangements counter–flow is the most efficient design because it transfers the greatest
amount of heat (Ankit R. Patel, 2013).
F. Joshua (2009), in his concentric tube heat exchanger (CHTX) design which
consists of a copper pipe of diameter 0.0127m that is enclosed by a bigger copper pipe of
diameter 0.0254m. The bigger pipe carries the cold water while the smaller copper pipe
conveys the hot water in a counter-current flow. He used the logarithmic mean temperature
difference (LMTD) to analyse the heat exchanger and found that the design was effective.
3. DESIGN CONSIDERATIONS
According to F. Joshua (2009), in designing heat exchangers, a number of factors that
need to be considered are:
1. Resistance to heat transfer should be minimized
2. The equipment should be sturdy.
3. Cost and material requirements should be kept low.
4. Corrosion should be avoided.
5. Pumping cost should be kept low.
6. Space required should be kept low.
7. Required weight should be kept low.
Design involves trade-off among factors not related to heat transfer. Meeting the
objective of minimized thermal resistance implies thin wall separating fluids. Thin walls may
not be compatible with sturdiness. Auxiliary steps may have to be taken, for instance, the use
of support plates for tubing, to realize sturdiness (Saunders, 1988). A heat exchanger
typically involves two flowing fluids separated by a solid wall. Heat is first transferred from
the hot fluid to the wall by convection through the wall by conduction and from the wall to
the cold fluid again by convection. Any radiation effects are usually included in the
convection heat transfer coefficients (Holman, 2002).
EFFECTIVENESS-NTU METHOD
One of the example of problem that occur in analysing the heat exchanger design is
the determination of heat transfer rate and the outlet temperature and inlet temperature of
both hot and cold fluids flow as the type and size of heat exchanger is prescribed. The log
mean temperature method (LMTD) which is commonly used in analysing the heat exchanger
can be used in this problem. However, the procedure on solving the problem will require
4. tedious iteration and therefore not practical. As a result, Kays and London (1984) came up
with the effectiveness-NTU method to simplify the analysis (Y. A. Cengel and A. J. Ghajar,
2011). They defined a dimensionless parameter called the heat exchanger effectiveness P
which is the ratio of actual heat transfer rate to the maximum possible heat transfer rate. For
the single-pass parallel-flow and counter-flow heat exchangers, P—NTU expressions are:
Where NTU = UA/Cmin is the number of transfer units, and C* = Cmin/Cmax is the
ratio of heat capacity rate of the fluid with the smaller heat capacity (hereafter, the minimum
fluid) to that of the fluid with the larger one (hereafter, the maximum fluid). P. Talukdar
(2011), state that the NTU method is mainly based on the dimensionless parameter called the
heat transfer effectiveness, ɛ, defined as below figure.
Figure 1: Effectiveness-NTU method calculation
Source: P. Talukdar (2011)
5. In order to determine the maximum heat transfer in a heat exchanger, the maximum
temperature difference that may occur must be considered. According to Y. A. Cengel and A.
J. Ghajar (2011), the heat exchanger will reach its maximum heat transfer rate if the outlet
temperature of the hot water channel is equal to the inlet temperature of the cold water
channel or anyway around.
Kays and London (1984), Shah and Sekulic (2003), and Shah and Pignotti (1992)
have presented effectiveness–NTU formulas for over 100 different heat exchanger flow
arrangements in the form of charts, tables and analytical closed-form P—NTU formulas. The
effectiveness–NTU method also offers advantages for the performance comparison between
various types of heat exchangers, that is from given value of NTU the goodness of the heat
exchanger can be easily identified from its value of P
PROJECT METHODOLOGY
In designing the heat exchanger test rig, several factor reviewed before need to be
considered in order to produce the lowest cost but effective design of heat exchanger. The
design of the heat exchanger is based on the situation taken from a swimming pool and a fish
pond during a hot sunny day or weather here in Malaysia. It was found that there might be an
increase of temperature to around 40°C due to the heat transfer from body source and the
surrounding temperature. Thus, an approach to design the simple and cost saving heat
exchanger is configured. The design of the heat exchanger test rig will consists of mainly two
parts which are:
1. Heat exchanger test rig table and tank
2. Heat exchanger flow and pipeline design
The design and analysis of these two parts will be conducted based on guidelines and
references from the previous study in order to maintain the reliability of the designs.
6. Figure 1: First design for table
Figure 2: Second design for table
8. Figure 1: The square hollow bars are measured and cut according to size
Figure 2: Raw material that has been cut according to size
9. Figure 3: Cutting the square hollow bar according to the design
Figure 4: Cutting the sheet metal by using sheet metal machine cutter
10. Figure 5: The fabricated parts before installations
Figure 6: Welding process
11. Figure 7: Tank attached to the table by using MIG
Figure 8: Pump with pipe assembled in and out connection
12. Figure 9: Painted table and tank as coating for corrosion protection
Figure 10: A fully assembled heat exchanger
13. DESIGN AND SIMULATION
Figure 1: P& ID drawing
The above Figure 1 shows the P&ID drawing of the whole structure of heat exchanger
test rig. It shows 2D drawing of the components include in the system. The components
involve in the system includes 90 elbow, standard tee joint, flexible hose, pump, water
heater and thermocouple. The purpose of having 2D drawing of P&ID drawing is to get the
clear view on how the system will work.
In order to analyse the structural design of the table and tank, a 3D model is designed
using the Solidworks software in order perform the Finite Element Analysis (FEA) on the
structure. The design is as shown below:
: PUMP
14. Figure 1: Table and tank Solidworks design
In this design, the dimension of each components involved is based on the actual
dimension used for the project. Each part is connected by weldments and in this design; the
weldment beads are applied to every connected faces of the components in order to achieve
the precise analysis for the whole process. The material is applied for each part according to
the list of materials used in the project.
Solidworks Simulation is used to analyse the design. The bottom faces of the table are
treated as fixed point in order to create a stable part analysis. A total of 500N forces is
applied to the whole part by considering the weight of the pump, and the weight of the water
used by referring to the calculations:
ρwater = 1000 kg/m3
Actual volume of water used = 1/2 of tank
= (0.5m) x (0.5m) x (0.175m)
= 0.0437 m3
Mass of water = (1000 kg/m3
) x (0.0437 m3
)
= 43.75 kg
15. Mass of pump = 6 kg
Total mass = 49.75 kg
Weight/Force = (49.75 kg) x (9.81 m/s2
)
= 488.04 N ≈ 500 N
By applying the total forces, the analysis is created and run. The results obtained from
the analysis include the displacement results, strain and stress results. The obtained analysis
results are as shown below.
Figure 2: Displacement result
From the displacement result, the highest obtained value is 2.782e-002 mm. As we
can see, the area that experiences the most displacement is mostly at the centre of the table
where the vertices of the tank create most pressure to the unsupported middle part of the
table. But, the design is consider acceptable due to the value of the highest displacement is
relatively small.The statement is strengthening by analysing the strain result. By looking to
the result as shown in figure 3 below, we can say that the area of the unsupported vertices of
the tank at the middle experienced the most strain as said before at which the Equivalent
Strain value is around 2.537 e-005.
16. Figure 3: Strain result
Moving to the stress result as shown in figure 4 below, the highest obtained stress
result at the area mentioned before is around 9000 Kn/m2
. The design can be considered as
acceptable because as we can see, not all the parts experienced the highest stress in the
system and the area at which the stress occur does not react proportionally to the highest
stress value.
Figure 4: Stress result
17. RESULTS AND DISCUSSIONS
1. Heat Transfer Rate
The heat transfer in a heat exchanger will reach its maximum value when the cold
fluid is heated to the inlet temperature of the hot fluid or the hot fluid is cooled to the inlet
temperature of the cold fluid. In this project, will examine and compare the difference
between the calculated theory results and also the experimental results to determine the
percentage error that may occur in our design experiment. The outlet temperature will be
estimated theoretically and will be compare to the achieve value of the project.
Theoretical:
Hot water (Inlet)
Tin = 38C
= 994.0kg/m3
k = 0.623W/Mk
= 0.720x10-3
kg/ms
Cp = 4178J/kgK
Q = 5.833x10-4
m3
/s
𝑚̇ = (5.833x10-4
m3
/s)(994.0kg/m3
)
= 0.5798kg/s
Cold Water (Inlet)
Tin = 30C
= 998.0 kg/m3
k = 0.598W/Mk
= 1.002x10-3
kg/ms
Cp = 4182J/kgK
18. Q = 1.5x10-4
m3
/s
𝑚̇ = (1.5x10-4
)(998)
= 0.1497kg/s
Ch = 𝑚̇ hCph
= (0.5789kg/s)(4.178kJ/kgK)
= 2422W/K
Cc = 𝑚̇ cCpc
= (0.1497kg/s)(4.182kJ/kgK)
= 626.05W/K
Therefore; Cmin = 626.05W/K
𝑄̇ = Cc (Tc,out – Tc,in)
Tc,out = Tc,in +
𝑄̇
𝐶𝑐
= 30 +
9390.75
626.05
= 45C
𝑄̇ = Ch (Th,in – Th,out)
Th,out = Th,in –
𝑄̇
𝐶ℎ
= 38C –
9390.75
2422
= 34C
2) Pipe friction loss
Pipe A (Hot Channel 38C):
1” ANSI schedule 40
Nominal diameter: 1 inch = 0.025 m
External diameter: 1.315 inch = 0.033 m
Internal diameter: 1.029 inch = 0.026 m
Area, A =
𝜋(𝐷𝑜2−𝐷𝑖2)
4
=
𝜋((0.033𝑚)2−(0.026𝑚)2)
4
= 3.244 x 10−4
𝑚2
Q = 5.833 x 10−4
𝑚3
/𝑠 (Pump flowrate
capacity)
V = Q / A
= (5.833 x 10−4
𝑚3
/𝑠) / (3.244 x 10−4
𝑚2
)
= 1.798 𝑚/𝑠
Total length: 1.867m
∆P =
𝜌𝑔𝐿𝑉2
𝐷2𝑔
=
(1000
𝑘𝑔
𝑚3)(9.81
𝑚
𝑠2)(1.867𝑚)(1.798 𝑚/𝑠)2
(0.026𝑚)2(9.81
𝑚
𝑠2)
19. = 8928.469Pa
Fittings:
Standard elbow 90 ̊ : k = 0.57
Standard Tee : k = 1.14
Pipe exit : k = 1.00
Pipe entrance: k = 0.78
h = kv2
/2g
h=
((2𝑥0.57)+(2𝑥1.14)+ (2𝑥1)+ 0.78) (1.798 𝑚/𝑠)2
2(9.81
𝑚
𝑠2)
= 0.568 m
∆P = 𝜌gh
= (1000
𝑘𝑔
𝑚3
) (9.81
𝑚
𝑠2
) (0.568 𝑚)
= 5573.8Pa
Total pressure loss :
∆P total = 8928.469Pa + 5573.8 Pa
= 8934.042Pa
Pipe B (Cold Channel 30C):
3/4” ANSI schedule 40
Nominal diameter: 3/4 inch = 0.019 m
External diameter: 1.050 inch = 0.027 m
Internal diameter: 0.804 inch = 0.020 m
Area, A =
𝜋(𝐷𝑜2−𝐷𝑖2)
4
=
𝜋((0.027𝑚)2−(0.020𝑚)2)
4
= 2.58 x 10−4
𝑚2
Q = 1.5 x 10−4
𝑚3
/𝑠 (estimation based on
average water flowrate in home supply)
V = Q / A
= (1.5 x 10−4
𝑚3
/𝑠) / (2.58 x 10−4
𝑚2
)
= 0.581 m/s
Total length: 1.08m
∆P =
𝜌𝑔𝐿𝑉2
𝐷2𝑔
=
(1000
𝑘𝑔
𝑚3)(9.81
𝑚
𝑠2)(1.08𝑚)(0.581 𝑚/𝑠)2
(0.020𝑚)2(9.81
𝑚
𝑠2)
= 911.415Pa
20. Fittings:
Pipe exit : k = 1.00
h = kv2
/2g
h =
( 1) (0.581𝑚/𝑠)2
2(9.81
𝑚
𝑠2)
= 0.0296 𝑚
∆P = 𝜌gh
= (1000
𝑘𝑔
𝑚3
) (9.81
𝑚
𝑠2
) (0.0296𝑚)
= 290.5 Pa
Experimental value:
Pipe A (Hot Channel):
Tin :37.6C
Tout: 37.3C
Percentage error:
𝑒𝑥𝑝𝑒𝑟𝑖𝑚𝑒𝑛𝑡𝑎𝑙 𝑣𝑎𝑙𝑢𝑒 − 𝑡ℎ𝑒𝑜𝑟𝑒𝑡𝑖𝑐𝑎𝑙 𝑣𝑎𝑙𝑢𝑒
𝑡ℎ𝑒𝑜𝑟𝑒𝑡𝑖𝑐𝑎𝑙 𝑣𝑎𝑙𝑢𝑒
Hot water (Inlet)
37.6 𝐶 − 38 𝐶
38 𝐶
𝑥 100%
=1.05%
Hot water (Outlet)
37.3 𝐶 − 34 𝐶
34 𝐶
𝑥 100%
=9.71%
The above calculations show the percentage error between experimental and
theoretical value is not big in difference. The percentage error for temperature of the hot
water inlet is about 1.05% while for the outlet is about 9.71%. The difference is might be due
to the heat release in any ways since the tank is not protected by any insulator.
21. CONCLUSION
In conclusion, there is a percentage error during the testing of the heat exchanger. In
order to prevent this error, controlling variable that can be controlled is by insulating the heat
exchanger with Styrofoam insulation sheets. The objective of this project is achieved. The
above calculations show the percentage error between experimental and theoretical value is
not big in difference. The percentage error for temperature of the hot water inlet is about
1.05% while for the outlet is about 9.71%. The difference is might be due to the heat release
in any ways since the tank is not protected by any insulator.
ACKNOWLEDGMENTS
The authors would like to say thanks to the lecturers and engineers in University
Malaysia Pahang (UMP) for guiding in completing this project and providing laboratory
facilities.
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