Bangladesh, a developing country is facing difficulty to achieve an overall sustained progress in... more Bangladesh, a developing country is facing difficulty to achieve an overall sustained progress in the economy due to the lack of a sound energy security. Immense quantity of energy is needed for the development and economic progress of the country. In this context, alternatives of conventional energy sources, renewable energy resources can be the sustainable solution for the energy security. The current demand for energy considerably increasing that was close to exceed the provision and forecast determines that this projection are going to be enlarged additional in close to future. Within the case of the rising energy drawback in Bangladesh, renewable energy particularly solar energy will play a major role during this case. This paper presents the summary of the renewable energy resources in Bangladesh and also the proportion of solar energy feasibility. It will additionally provide the key points of obstacles to implement the use of solar energy in Bangladesh and moreover as government policies and future conceive to overcome this case. When considering all the matter, the solar energy in some regions is satisfactory to operate pumps and additionally for generation of electricity. In this paper, future prospect of solar energy in Bangladesh have been reviewed comprehensively and presented. This work compiles latest literatures in terms of journal articles, conference proceedings, web materials, reports, books, thesis, handbooks on energy and renewable energy resources in Bangladesh.
With its strong influence on the country's economic and industrial development it is indeed one o... more With its strong influence on the country's economic and industrial development it is indeed one of the major drivers of our economy. Moreover, economic liberalization coupled with its technological, cost and manpower advantage have made Bangladesh one of the prime business destination for many global automotive players. The sector has moderate direct employment and significant indirect employment; it is estimated that the sector provides direct and indirect employment to over 3 million people. This paper will hopefully be able to answer most of the questions arises against of the importance of HR policy in automobile industry and the guideline to the pathway of HR policy in Bangladesh. The result of the analyses performed was the development of an original theoretical framework which aims to help managers understand and analyze flexibility and its relationship with unplanned change in manufacturing systems.
The effects of heat pipes of different lengths and orientations on its thermal performances are e... more The effects of heat pipes of different lengths and orientations on its thermal performances are experimentally investigated in this study. Heat is transferred from the evaporator section to the condenser section and finally dissipated to the environment. Heat pipe evaporator section is heated by electric heater and condenser section is cooled by forced convection of water circulation. For the precise measurement of the maximum heat transfer capability, heat inputs are increased in small steps of 2 W. Tests have conducted by using two different lengths (150 mm, 200mm) of heat pipe having same hydraulic diameter (D=3mm). The results indicate that with the increase in length heat transfer coefficient increases and thermal resistance decreases.
The automobile repairing industry in Bangladesh is growing at a very rapid pace but the quality s... more The automobile repairing industry in Bangladesh is growing at a very rapid pace but the quality still doesn't reach to the topmost mark. Due to advancement in vehicle technology the service requirement of vehicles has also become technology dependent. Demand of highly skilled workers is on the rise. Hence, there is growing demand for organized service retailing. The objective of this paper is to understand the market potentiality, existing condition of automobile repairing business industry, recent problem in automobile servicing business & a guideline of quality service. We describe the problems encountered by the client and how the simulation study illuminated a pathway to significant improvements in customer service and financial profitability. To understand the situation of automobile business in Bangladesh , a representative survey of customers, owners of different automobile workshop; technicians involved in this business and spare parts sellers was conducted. A secondary source was collected data from BRTA, automobile industry journal, internet sources; data published from business organization has been used for analyzing the situation. Necessary suggestions have been made and service center has started executing them for the improvement in current service quality level and improve their business performance.
Automobile industry in Bangladesh is growing at rapid pace but quality both at production & servi... more Automobile industry in Bangladesh is growing at rapid pace but quality both at production & service still has not reached to the topmost mark. Due to advancement in vehicle technology the service requirements of vehicles has become technology dependent. Moreover, demand of highly skilled workers is on the rise. This paper is focusing on build up " MOTOR HOSPICE " ; it's the market potentiality analysis and a guideline for quality automobile service in Bangladesh. To improve the existing situation of automobile business in Bangladesh, a model has been developed based on the customers of vehicles, owners of different automobile workshops; technicians involved in this business and spare parts sellers was conducted along with the data collected from internet. Necessary suggestions have been made and service center has started executing them for the improvement in current service quality level and improved their business performances.
The primary objective of every power plant owner is to get constructed and to operate his plant a... more The primary objective of every power plant owner is to get constructed and to operate his plant as cost-effectively as possible to maximize his profit. This means that he has to minimize – besides the investment costs for construction-the life cycle costs, which are influenced by different factors. One of them is the operation and maintenance (O&M) cost incurrent in course of operation period of the power plant. The power plant utilities are further driven to reduce their life cycle costs by the deregulation of the different power markets. Cost reduction by outsourcing of operation and maintenance (O&M) activities is one opportunity to meet such requirements. This paper shall give an overview of the O&M Services operated by different plant shown on different examples in Bangladesh as well as the approach to customize services in compliance with different clients and market requirements.
MHD power plants can be built as new stand-alone or combined cycle plants or an MHD plant can be ... more MHD power plants can be built as new stand-alone or combined cycle plants or an MHD plant can be added on i.e. retro fitted to an existing plant. A retrofit option is particularly attractive for older plants that have to be reconditioned since these may increase the generating capacity of the existing plants and at the same time, reduce the emission of pollutants and cooling water requirements. This would extend the life of an existing power plant and improve its environmental intrusion. This paper describes system planning and power system integration of a model MHD power plant. Many of the thermal power plants commissioned in Bangladesh are 30-40 years old. Retrofitted MHD power plants may be an option to increase the performance of these plants as there remains a large coal reserve in Bangladesh where the gas reserve is approaching towards its end. The feasibility studies of MHD plants demonstrated that combined cycles using both open and closed cycle MHD processes should be economically competitive. The technology has reached the stage where the feasibility of retrofit demonstration plant is considered by several countries including USA, Russia, China, Japan, India and Australia. A developing country like Bangladesh may step forward to adopt the technology to handle its recent energy crisis.
In this titled paper the optimization of a stroller components in computer aided design (CAD)-bas... more In this titled paper the optimization of a stroller components in computer aided design (CAD)-based on a structural optimization problem. A methodology for the efficient solution of the corresponding design optimization problems is presented. Each design criterion as well as the constraints imposed on the design variables and problem parameters are characterized by preference functions. High-quality approximations for the system response functions are constructed using the concepts of intermediate response quantities and intermediate variables. And simulation also tries to extract the relationship of deformation, mass and other design parameters by the deterministic method through sensitivities and response. Application programs developed to integrate commercially available CAD/CAM/FEA/Design optimization tools enable implementation in virtual environment and facilitate automation. The application programs can be reused for similar design problems provided that the same set of tools is used. In case of solution method sensitivity analysis were also conducted.
In the field of automobile seat is an important part which plays a great significance in case of ... more In the field of automobile seat is an important part which plays a great significance in case of safety and accidental analysis. Whiplashes injuries are one of the most common injuries reported from automotive rear-end collisions. Automobile seat back and head restraint plays a safety role to reduce the neck injury during low speed rear-end-collisions. In this paper we are giving a brief idea about the reactive headrest mechanism and also how it is effected the head restraint it is also showed. Here by the help of the kinematical modeling with help of inverse kinematics and MATLAB program we are demonstrated a virtual link mechanism for the seat back to control the backset and height. Contact will also be controlled by the help of this kinematic model in case of the dynamic conditions. The mathematic and kinematic model was demonstrated and analyzed. The feasibility was also proved by the help of the computer simulation.
This paper deals with the investigation carried out to explore the mixed convection heat transfer... more This paper deals with the investigation carried out to explore the mixed convection heat transfer characteristics in an enclosure with isothermally heated baffle. The two dimensional momentum equation, energy equation and continuity equation is used as the governing equation. Finite difference method has been used to solve the above governing equations in the form of stream function and vorticity formulation by SUR method. The dimensionless length of the enclosure is considered as L=2 and the dimensionless height of the enclosure is considered as H=3. All walls are assumed to be insulated. The Reynolds number, Richardson number and baffle length varies ranging from 10 ≤ Re ≤ 300, 0 ≤ Ri ≤ 2 and 0.5 ≤ F ≤ 1.5 respectively. The fluid flow characteristics have been presented for different Re, Ri and F. It is observed that the size of recirculation is varies with Re and Ri. It is observed that the average Nusselt no decreases with the increase of Ri. The average Nusselt number decreases with the increase of baffle length. The heating efficiency increases with the increase of Richardson number and Reynolds number but decreases with the increase of baffle length.
Bangladesh, a developing country requires huge amount of energy for its development and economic ... more Bangladesh, a developing country requires huge amount of energy for its development and economic growth. But current demand for energy significantly increasing which was about to exceed the availability and forecast determines that this projection will be increased more in near future. In the case of the emerging energy problem in Bangladesh, sustainable energy specially wind energy can play a significant role in this case. This paper presents the overview of the Renewable Energy Resources in Bangladesh and the percentage of wind energy feasibility. It also emphasis on average speed vs time duration, speed vs location as well. It is also provided the information obstracle to impliment of wind energy in Bangladesh and as well as government policies and future plan to overcome this situation. After considering all the problem, The wind speed in some regions is satisfactory for operating pumps and also for generation of electricity.
The use of CNG in Bangladesh is increasing day by day due to the environmental benefits as well a... more The use of CNG in Bangladesh is increasing day by day due to the environmental benefits as well as economic benefits. In the last decade, the importance of environment conservation has assumed great significance. Even in Bangladesh the last couple of years have witnessed a greater devotion and awakening towards the protection of the environment. Pollution due to petroleum products used in transportation is an ever-increasing problem for Bangladesh like other country. So alternative solution of energy source is trying to use, thus pressure on Compressed Natural Gas (CNG) has been increased. Though, the environmental problem is solved but the stock of gas is simultaneously decreasing. The purpose of the study is to make coordination between the environmental awareness concept and the use of the natural gas should be connected in such a manner to achieve the success of Bangladesh.
This paper presents, a numerical study on mixed convective heat transfer of a two dimensional ver... more This paper presents, a numerical study on mixed convective heat transfer of a two dimensional vertical ventilated enclosure with variations of different parameters. All walls are assumed to be adiabatic, but baffle is considered as isothermally heated. Cold air enters the enclosure through an opening from bottom of the left vertical wall and become heated, exits from the top of the right vertical wall. A finite difference method is used for the simulation. The discritized equations with specified boundary conditions are sought by Successive Under Relaxation (SUR) method. It has been done on the basis of stream function and vorticity formulation of the two dimensional Navier-Stokes equation, continuity equation and the temperature distribution at all nodes is calculated by solving energy equation. The investigation carried out with a Reynolds number in the range of 50 ≤ Re ≤ 300, Prandtl number 0.01 ≤ Pr ≤ 2.0 and Richardson number 0 ≤ Ri ≤ 10. The objective of this study is to observed the effect variations of the Richardson number, Prandtl number and Reynolds number for maximum heating efficiency. The maximum heating efficiency is observed at the higher value of Reynolds number and higher value of Richardson number.
The use of CNG in Bangladesh is increasing day by day due to the environmental benefits as well a... more The use of CNG in Bangladesh is increasing day by day due to the environmental benefits as well as economic benefits. In the last decade, the importance of environment conservation has assumed great significance. Even in Bangladesh the last couple of years have witnessed a greater devotion and awakening towards the protection of the environment. Pollution due to petroleum products used in transportation is an ever-increasing problem for Bangladesh like other country. So alternative solution of energy source is trying to use, thus pressure on Compressed Natural Gas (CNG) has been increased. Thus, the environmental problem is solved but the stock of gas is simultaneously decreasing and the stress comes on the transportation sector in Bangladesh. The purpose of the study is to make coordination between the transportation sector and the use of the natural gas should be connected in such a manner to achieve the success of Bangladesh.
Bangladesh transport sector is still heavily dependent on imported oil in an effort to support it... more Bangladesh transport sector is still heavily dependent on imported oil in an effort to support its growing economy. The volatile oil prices and the unstable political situation of the Middle East, put the government of Bangladesh in a politically compromising position and force the country to a big amount of financial loss every year in the fuel and energy sector. Becoming energy independent has been a long-term goal for Bangladesh, a logical governmental goal is to decrease use of fossil fuel and increase use of domestically produced alternative energy sources. Adopting compressed natural gas (CNG) and Liquefied Petroleum Gas (LPG) in old vehicles and encouraging alternative fuel driven vehicles and electric vehicles in Bangladesh would improve national, political and environmental standing. Imposing new rules and VAT and Taxes on both CNG conversion product and recondition car, CNG and LNG sectors are going towards downstream. The government of Bangladesh should take necessary steps in well advance to make clean and environment friendly transportation systems and to become energy independent country. Thus, the market of alternative fuel driven vehicle has got a chance to explore to meet the future challenge. This paper shows how to meet the future challenge of the vehicular fuels in Bangladesh.
A numerical study was carried out to investigate the mixed convective two dimensional flows in a ... more A numerical study was carried out to investigate the mixed convective two dimensional flows in a vertical enclosure with heated baffles on side walls. All walls are assumed to be adiabatic, but baffles are considered as isothermally heated. Thus, cold flow is imposed through an opening at the bottom of the left wall and by taking heat from the baffles the fluid becomes heated and exits through outlet at the top of the right wall of the enclosure. Heated baffles are placed both at the left and right wall of the enclosure. The present study simulates a practical system such as a silencer. The consequent mathematical model is governed by the coupled equations of mass, momentum and energy and these equations are discritized. The discritized equations with specified boundary conditions are sought by Successive under Relaxation (SUR) method. A wide range of pertinent parameters such as Reynolds number 50 ≤ Re ≤ 300, Richardson number 0 ≤ Ri ≤ 10 and Prandtl number 0.01 ≤ Pr ≤ 2.0 are considered in the present study. Various results such as the streamlines, isotherms, heat transfer rates in terms of the average Nusselt number and temperature and also heating efficiency in the enclosure are presented for different parameters. It is observed that Maximum heating efficiency is found at higher value of Reynolds and Richardson number.
An analytical method and an associated computer program are developed for forward kinematics solu... more An analytical method and an associated computer program are developed for forward kinematics solution of a class of robotic manipulators in case of design the virtual link connection of automotive seat back, in which four joint variables are contained. For this case, it becomes possible to express all the other joint variables in terms of a selected one, and this reduces the forward kinematics problem to solving a non-linear scalar equation having the selected joint variable as the only unknown. The solution can be obtained by iterative methods and the remaining joint variables can easily be computed by using the solved joint variable. Since the method is manipulator dependent, the equations will be different for kinematical designs, and should be obtained analytically in the iterative way by the help of the MATLAB program. The developed method shows the reduction in the important factor which known as the backset and the contact time in both static and dynamic condition.
In the last decade, the importance of environment conservation has assumed great significance. Ev... more In the last decade, the importance of environment conservation has assumed great significance. Even in Bangladesh the last couple of years have witnessed a greater devotion and awakening towards the protection of the environment. Pollution due to petroleum products used in transportation is an ever-increasing problem for Bangladesh like other country. So alternative solution of energy source is trying to use, thus pressure on Compressed Natural Gas (CNG) has been increased. Though, the environmental problem is solved but the stock of gas is simultaneously decreasing. The use of CNG as an alternative vehicular fuel in Bangladesh is increasing day by day because the country has a significant natural gas resources and the gas transmission and distribution network is also well developed. The government of Bangladesh is taking few steps for coordination between the environmental awareness concept and the use of the CNG in sectors. The purpose of the study is to find out present scenario of Bangladesh of using CNG as vehicular fuel and find out some proper ways for the environmental and economic benefits of the country. And the commercialization of CNG as well as the growth pattern of CNG conversion workshops in Bangladesh.
A numerical study is conducted to investigate the fluid flow and heat transfer characteristics in... more A numerical study is conducted to investigate the fluid flow and heat transfer characteristics in a vertical ventilated enclosure with baffle placed at the side wall and all walls are assumed adiabatic. An external cold fluid flow enters into the enclosure through an opening over the left vertical wall and is exited through an outlet in opposite side wall. The two dimensional mathematical models includes the systems of four partial differential equations of continuity, Navier-Stokes equation and energy equation solved by the finite difference method. Uniform grids are used in entire computational domain. The differential equations are discretized using Central Difference Method and Forward difference method. The discritized equations with proper boundary conditions of numerical solutions are sought by obtaining Leibmann’s Successive under Relaxation (SUR) method. It has been done on the basis of stream function and vorticity formulation of the two dimensional Navier-Stokes equation and continuity equation and then the temperature distribution at all nodes is calculated by solving Energy equation. The flow field is investigated by numerical simulations for fluid flowing with a Reynolds number in the range 50Re300 for Prandtl number 0.01Pr 2.0 and Richardson number 0≤Ri≤10. Numerical results are obtained for different values of Reynolds number, Prandtl number & Richardson number. Heat transfer rates at the heated baffle is presented in terms of average Nusselt Number .It is observed that maximum heating efficiency is achieved with this configuration for the higher values of Reynolds number, Richardson number and Prandtl number. As the length of baffle increases the heating efficiency decreases.
Bangladesh, a developing country is facing difficulty to achieve an overall sustained progress in... more Bangladesh, a developing country is facing difficulty to achieve an overall sustained progress in the economy due to the lack of a sound energy security. Immense quantity of energy is needed for the development and economic progress of the country. In this context, alternatives of conventional energy sources, renewable energy resources can be the sustainable solution for the energy security. The current demand for energy considerably increasing that was close to exceed the provision and forecast determines that this projection are going to be enlarged additional in close to future. Within the case of the rising energy drawback in Bangladesh, renewable energy particularly solar energy will play a major role during this case. This paper presents the summary of the renewable energy resources in Bangladesh and also the proportion of solar energy feasibility. It will additionally provide the key points of obstacles to implement the use of solar energy in Bangladesh and moreover as government policies and future conceive to overcome this case. When considering all the matter, the solar energy in some regions is satisfactory to operate pumps and additionally for generation of electricity. In this paper, future prospect of solar energy in Bangladesh have been reviewed comprehensively and presented. This work compiles latest literatures in terms of journal articles, conference proceedings, web materials, reports, books, thesis, handbooks on energy and renewable energy resources in Bangladesh.
With its strong influence on the country's economic and industrial development it is indeed one o... more With its strong influence on the country's economic and industrial development it is indeed one of the major drivers of our economy. Moreover, economic liberalization coupled with its technological, cost and manpower advantage have made Bangladesh one of the prime business destination for many global automotive players. The sector has moderate direct employment and significant indirect employment; it is estimated that the sector provides direct and indirect employment to over 3 million people. This paper will hopefully be able to answer most of the questions arises against of the importance of HR policy in automobile industry and the guideline to the pathway of HR policy in Bangladesh. The result of the analyses performed was the development of an original theoretical framework which aims to help managers understand and analyze flexibility and its relationship with unplanned change in manufacturing systems.
The effects of heat pipes of different lengths and orientations on its thermal performances are e... more The effects of heat pipes of different lengths and orientations on its thermal performances are experimentally investigated in this study. Heat is transferred from the evaporator section to the condenser section and finally dissipated to the environment. Heat pipe evaporator section is heated by electric heater and condenser section is cooled by forced convection of water circulation. For the precise measurement of the maximum heat transfer capability, heat inputs are increased in small steps of 2 W. Tests have conducted by using two different lengths (150 mm, 200mm) of heat pipe having same hydraulic diameter (D=3mm). The results indicate that with the increase in length heat transfer coefficient increases and thermal resistance decreases.
The automobile repairing industry in Bangladesh is growing at a very rapid pace but the quality s... more The automobile repairing industry in Bangladesh is growing at a very rapid pace but the quality still doesn't reach to the topmost mark. Due to advancement in vehicle technology the service requirement of vehicles has also become technology dependent. Demand of highly skilled workers is on the rise. Hence, there is growing demand for organized service retailing. The objective of this paper is to understand the market potentiality, existing condition of automobile repairing business industry, recent problem in automobile servicing business & a guideline of quality service. We describe the problems encountered by the client and how the simulation study illuminated a pathway to significant improvements in customer service and financial profitability. To understand the situation of automobile business in Bangladesh , a representative survey of customers, owners of different automobile workshop; technicians involved in this business and spare parts sellers was conducted. A secondary source was collected data from BRTA, automobile industry journal, internet sources; data published from business organization has been used for analyzing the situation. Necessary suggestions have been made and service center has started executing them for the improvement in current service quality level and improve their business performance.
Automobile industry in Bangladesh is growing at rapid pace but quality both at production & servi... more Automobile industry in Bangladesh is growing at rapid pace but quality both at production & service still has not reached to the topmost mark. Due to advancement in vehicle technology the service requirements of vehicles has become technology dependent. Moreover, demand of highly skilled workers is on the rise. This paper is focusing on build up " MOTOR HOSPICE " ; it's the market potentiality analysis and a guideline for quality automobile service in Bangladesh. To improve the existing situation of automobile business in Bangladesh, a model has been developed based on the customers of vehicles, owners of different automobile workshops; technicians involved in this business and spare parts sellers was conducted along with the data collected from internet. Necessary suggestions have been made and service center has started executing them for the improvement in current service quality level and improved their business performances.
The primary objective of every power plant owner is to get constructed and to operate his plant a... more The primary objective of every power plant owner is to get constructed and to operate his plant as cost-effectively as possible to maximize his profit. This means that he has to minimize – besides the investment costs for construction-the life cycle costs, which are influenced by different factors. One of them is the operation and maintenance (O&M) cost incurrent in course of operation period of the power plant. The power plant utilities are further driven to reduce their life cycle costs by the deregulation of the different power markets. Cost reduction by outsourcing of operation and maintenance (O&M) activities is one opportunity to meet such requirements. This paper shall give an overview of the O&M Services operated by different plant shown on different examples in Bangladesh as well as the approach to customize services in compliance with different clients and market requirements.
MHD power plants can be built as new stand-alone or combined cycle plants or an MHD plant can be ... more MHD power plants can be built as new stand-alone or combined cycle plants or an MHD plant can be added on i.e. retro fitted to an existing plant. A retrofit option is particularly attractive for older plants that have to be reconditioned since these may increase the generating capacity of the existing plants and at the same time, reduce the emission of pollutants and cooling water requirements. This would extend the life of an existing power plant and improve its environmental intrusion. This paper describes system planning and power system integration of a model MHD power plant. Many of the thermal power plants commissioned in Bangladesh are 30-40 years old. Retrofitted MHD power plants may be an option to increase the performance of these plants as there remains a large coal reserve in Bangladesh where the gas reserve is approaching towards its end. The feasibility studies of MHD plants demonstrated that combined cycles using both open and closed cycle MHD processes should be economically competitive. The technology has reached the stage where the feasibility of retrofit demonstration plant is considered by several countries including USA, Russia, China, Japan, India and Australia. A developing country like Bangladesh may step forward to adopt the technology to handle its recent energy crisis.
In this titled paper the optimization of a stroller components in computer aided design (CAD)-bas... more In this titled paper the optimization of a stroller components in computer aided design (CAD)-based on a structural optimization problem. A methodology for the efficient solution of the corresponding design optimization problems is presented. Each design criterion as well as the constraints imposed on the design variables and problem parameters are characterized by preference functions. High-quality approximations for the system response functions are constructed using the concepts of intermediate response quantities and intermediate variables. And simulation also tries to extract the relationship of deformation, mass and other design parameters by the deterministic method through sensitivities and response. Application programs developed to integrate commercially available CAD/CAM/FEA/Design optimization tools enable implementation in virtual environment and facilitate automation. The application programs can be reused for similar design problems provided that the same set of tools is used. In case of solution method sensitivity analysis were also conducted.
In the field of automobile seat is an important part which plays a great significance in case of ... more In the field of automobile seat is an important part which plays a great significance in case of safety and accidental analysis. Whiplashes injuries are one of the most common injuries reported from automotive rear-end collisions. Automobile seat back and head restraint plays a safety role to reduce the neck injury during low speed rear-end-collisions. In this paper we are giving a brief idea about the reactive headrest mechanism and also how it is effected the head restraint it is also showed. Here by the help of the kinematical modeling with help of inverse kinematics and MATLAB program we are demonstrated a virtual link mechanism for the seat back to control the backset and height. Contact will also be controlled by the help of this kinematic model in case of the dynamic conditions. The mathematic and kinematic model was demonstrated and analyzed. The feasibility was also proved by the help of the computer simulation.
This paper deals with the investigation carried out to explore the mixed convection heat transfer... more This paper deals with the investigation carried out to explore the mixed convection heat transfer characteristics in an enclosure with isothermally heated baffle. The two dimensional momentum equation, energy equation and continuity equation is used as the governing equation. Finite difference method has been used to solve the above governing equations in the form of stream function and vorticity formulation by SUR method. The dimensionless length of the enclosure is considered as L=2 and the dimensionless height of the enclosure is considered as H=3. All walls are assumed to be insulated. The Reynolds number, Richardson number and baffle length varies ranging from 10 ≤ Re ≤ 300, 0 ≤ Ri ≤ 2 and 0.5 ≤ F ≤ 1.5 respectively. The fluid flow characteristics have been presented for different Re, Ri and F. It is observed that the size of recirculation is varies with Re and Ri. It is observed that the average Nusselt no decreases with the increase of Ri. The average Nusselt number decreases with the increase of baffle length. The heating efficiency increases with the increase of Richardson number and Reynolds number but decreases with the increase of baffle length.
Bangladesh, a developing country requires huge amount of energy for its development and economic ... more Bangladesh, a developing country requires huge amount of energy for its development and economic growth. But current demand for energy significantly increasing which was about to exceed the availability and forecast determines that this projection will be increased more in near future. In the case of the emerging energy problem in Bangladesh, sustainable energy specially wind energy can play a significant role in this case. This paper presents the overview of the Renewable Energy Resources in Bangladesh and the percentage of wind energy feasibility. It also emphasis on average speed vs time duration, speed vs location as well. It is also provided the information obstracle to impliment of wind energy in Bangladesh and as well as government policies and future plan to overcome this situation. After considering all the problem, The wind speed in some regions is satisfactory for operating pumps and also for generation of electricity.
The use of CNG in Bangladesh is increasing day by day due to the environmental benefits as well a... more The use of CNG in Bangladesh is increasing day by day due to the environmental benefits as well as economic benefits. In the last decade, the importance of environment conservation has assumed great significance. Even in Bangladesh the last couple of years have witnessed a greater devotion and awakening towards the protection of the environment. Pollution due to petroleum products used in transportation is an ever-increasing problem for Bangladesh like other country. So alternative solution of energy source is trying to use, thus pressure on Compressed Natural Gas (CNG) has been increased. Though, the environmental problem is solved but the stock of gas is simultaneously decreasing. The purpose of the study is to make coordination between the environmental awareness concept and the use of the natural gas should be connected in such a manner to achieve the success of Bangladesh.
This paper presents, a numerical study on mixed convective heat transfer of a two dimensional ver... more This paper presents, a numerical study on mixed convective heat transfer of a two dimensional vertical ventilated enclosure with variations of different parameters. All walls are assumed to be adiabatic, but baffle is considered as isothermally heated. Cold air enters the enclosure through an opening from bottom of the left vertical wall and become heated, exits from the top of the right vertical wall. A finite difference method is used for the simulation. The discritized equations with specified boundary conditions are sought by Successive Under Relaxation (SUR) method. It has been done on the basis of stream function and vorticity formulation of the two dimensional Navier-Stokes equation, continuity equation and the temperature distribution at all nodes is calculated by solving energy equation. The investigation carried out with a Reynolds number in the range of 50 ≤ Re ≤ 300, Prandtl number 0.01 ≤ Pr ≤ 2.0 and Richardson number 0 ≤ Ri ≤ 10. The objective of this study is to observed the effect variations of the Richardson number, Prandtl number and Reynolds number for maximum heating efficiency. The maximum heating efficiency is observed at the higher value of Reynolds number and higher value of Richardson number.
The use of CNG in Bangladesh is increasing day by day due to the environmental benefits as well a... more The use of CNG in Bangladesh is increasing day by day due to the environmental benefits as well as economic benefits. In the last decade, the importance of environment conservation has assumed great significance. Even in Bangladesh the last couple of years have witnessed a greater devotion and awakening towards the protection of the environment. Pollution due to petroleum products used in transportation is an ever-increasing problem for Bangladesh like other country. So alternative solution of energy source is trying to use, thus pressure on Compressed Natural Gas (CNG) has been increased. Thus, the environmental problem is solved but the stock of gas is simultaneously decreasing and the stress comes on the transportation sector in Bangladesh. The purpose of the study is to make coordination between the transportation sector and the use of the natural gas should be connected in such a manner to achieve the success of Bangladesh.
Bangladesh transport sector is still heavily dependent on imported oil in an effort to support it... more Bangladesh transport sector is still heavily dependent on imported oil in an effort to support its growing economy. The volatile oil prices and the unstable political situation of the Middle East, put the government of Bangladesh in a politically compromising position and force the country to a big amount of financial loss every year in the fuel and energy sector. Becoming energy independent has been a long-term goal for Bangladesh, a logical governmental goal is to decrease use of fossil fuel and increase use of domestically produced alternative energy sources. Adopting compressed natural gas (CNG) and Liquefied Petroleum Gas (LPG) in old vehicles and encouraging alternative fuel driven vehicles and electric vehicles in Bangladesh would improve national, political and environmental standing. Imposing new rules and VAT and Taxes on both CNG conversion product and recondition car, CNG and LNG sectors are going towards downstream. The government of Bangladesh should take necessary steps in well advance to make clean and environment friendly transportation systems and to become energy independent country. Thus, the market of alternative fuel driven vehicle has got a chance to explore to meet the future challenge. This paper shows how to meet the future challenge of the vehicular fuels in Bangladesh.
A numerical study was carried out to investigate the mixed convective two dimensional flows in a ... more A numerical study was carried out to investigate the mixed convective two dimensional flows in a vertical enclosure with heated baffles on side walls. All walls are assumed to be adiabatic, but baffles are considered as isothermally heated. Thus, cold flow is imposed through an opening at the bottom of the left wall and by taking heat from the baffles the fluid becomes heated and exits through outlet at the top of the right wall of the enclosure. Heated baffles are placed both at the left and right wall of the enclosure. The present study simulates a practical system such as a silencer. The consequent mathematical model is governed by the coupled equations of mass, momentum and energy and these equations are discritized. The discritized equations with specified boundary conditions are sought by Successive under Relaxation (SUR) method. A wide range of pertinent parameters such as Reynolds number 50 ≤ Re ≤ 300, Richardson number 0 ≤ Ri ≤ 10 and Prandtl number 0.01 ≤ Pr ≤ 2.0 are considered in the present study. Various results such as the streamlines, isotherms, heat transfer rates in terms of the average Nusselt number and temperature and also heating efficiency in the enclosure are presented for different parameters. It is observed that Maximum heating efficiency is found at higher value of Reynolds and Richardson number.
An analytical method and an associated computer program are developed for forward kinematics solu... more An analytical method and an associated computer program are developed for forward kinematics solution of a class of robotic manipulators in case of design the virtual link connection of automotive seat back, in which four joint variables are contained. For this case, it becomes possible to express all the other joint variables in terms of a selected one, and this reduces the forward kinematics problem to solving a non-linear scalar equation having the selected joint variable as the only unknown. The solution can be obtained by iterative methods and the remaining joint variables can easily be computed by using the solved joint variable. Since the method is manipulator dependent, the equations will be different for kinematical designs, and should be obtained analytically in the iterative way by the help of the MATLAB program. The developed method shows the reduction in the important factor which known as the backset and the contact time in both static and dynamic condition.
In the last decade, the importance of environment conservation has assumed great significance. Ev... more In the last decade, the importance of environment conservation has assumed great significance. Even in Bangladesh the last couple of years have witnessed a greater devotion and awakening towards the protection of the environment. Pollution due to petroleum products used in transportation is an ever-increasing problem for Bangladesh like other country. So alternative solution of energy source is trying to use, thus pressure on Compressed Natural Gas (CNG) has been increased. Though, the environmental problem is solved but the stock of gas is simultaneously decreasing. The use of CNG as an alternative vehicular fuel in Bangladesh is increasing day by day because the country has a significant natural gas resources and the gas transmission and distribution network is also well developed. The government of Bangladesh is taking few steps for coordination between the environmental awareness concept and the use of the CNG in sectors. The purpose of the study is to find out present scenario of Bangladesh of using CNG as vehicular fuel and find out some proper ways for the environmental and economic benefits of the country. And the commercialization of CNG as well as the growth pattern of CNG conversion workshops in Bangladesh.
A numerical study is conducted to investigate the fluid flow and heat transfer characteristics in... more A numerical study is conducted to investigate the fluid flow and heat transfer characteristics in a vertical ventilated enclosure with baffle placed at the side wall and all walls are assumed adiabatic. An external cold fluid flow enters into the enclosure through an opening over the left vertical wall and is exited through an outlet in opposite side wall. The two dimensional mathematical models includes the systems of four partial differential equations of continuity, Navier-Stokes equation and energy equation solved by the finite difference method. Uniform grids are used in entire computational domain. The differential equations are discretized using Central Difference Method and Forward difference method. The discritized equations with proper boundary conditions of numerical solutions are sought by obtaining Leibmann’s Successive under Relaxation (SUR) method. It has been done on the basis of stream function and vorticity formulation of the two dimensional Navier-Stokes equation and continuity equation and then the temperature distribution at all nodes is calculated by solving Energy equation. The flow field is investigated by numerical simulations for fluid flowing with a Reynolds number in the range 50Re300 for Prandtl number 0.01Pr 2.0 and Richardson number 0≤Ri≤10. Numerical results are obtained for different values of Reynolds number, Prandtl number & Richardson number. Heat transfer rates at the heated baffle is presented in terms of average Nusselt Number .It is observed that maximum heating efficiency is achieved with this configuration for the higher values of Reynolds number, Richardson number and Prandtl number. As the length of baffle increases the heating efficiency decreases.
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vertical ventilated enclosure with baffle placed at the side wall and all walls are assumed
adiabatic. An external cold fluid flow enters into the enclosure through an opening over the left
vertical wall and is exited through an outlet in opposite side wall. The two dimensional
mathematical models includes the systems of four partial differential equations of continuity,
Navier-Stokes equation and energy equation solved by the finite difference method. Uniform
grids are used in entire computational domain. The differential equations are discretized using
Central Difference Method and Forward difference method. The discritized equations with
proper boundary conditions of numerical solutions are sought by obtaining Leibmann’s
Successive under Relaxation (SUR) method. It has been done on the basis of stream function
and vorticity formulation of the two dimensional Navier-Stokes equation and continuity equation
and then the temperature distribution at all nodes is calculated by solving Energy equation. The
flow field is investigated by numerical simulations for fluid flowing with a Reynolds number in
the range 50Re300 for Prandtl number 0.01Pr 2.0 and Richardson number 0≤Ri≤10.
Numerical results are obtained for different values of Reynolds number, Prandtl number &
Richardson number. Heat transfer rates at the heated baffle is presented in terms of average
Nusselt Number .It is observed that maximum heating efficiency is achieved with this
configuration for the higher values of Reynolds number, Richardson number and Prandtl
number. As the length of baffle increases the heating efficiency decreases.
vertical ventilated enclosure with baffle placed at the side wall and all walls are assumed
adiabatic. An external cold fluid flow enters into the enclosure through an opening over the left
vertical wall and is exited through an outlet in opposite side wall. The two dimensional
mathematical models includes the systems of four partial differential equations of continuity,
Navier-Stokes equation and energy equation solved by the finite difference method. Uniform
grids are used in entire computational domain. The differential equations are discretized using
Central Difference Method and Forward difference method. The discritized equations with
proper boundary conditions of numerical solutions are sought by obtaining Leibmann’s
Successive under Relaxation (SUR) method. It has been done on the basis of stream function
and vorticity formulation of the two dimensional Navier-Stokes equation and continuity equation
and then the temperature distribution at all nodes is calculated by solving Energy equation. The
flow field is investigated by numerical simulations for fluid flowing with a Reynolds number in
the range 50Re300 for Prandtl number 0.01Pr 2.0 and Richardson number 0≤Ri≤10.
Numerical results are obtained for different values of Reynolds number, Prandtl number &
Richardson number. Heat transfer rates at the heated baffle is presented in terms of average
Nusselt Number .It is observed that maximum heating efficiency is achieved with this
configuration for the higher values of Reynolds number, Richardson number and Prandtl
number. As the length of baffle increases the heating efficiency decreases.