The Experts below are selected from a list of 3384 Experts worldwide ranked by ideXlab platform
Vali Alimirzaloo - One of the best experts on this subject based on the ideXlab platform.
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Investigation on Forming of Titanium Bipolar Plates Using Micro-stamping Process
International Journal of Engineering, 2020Co-Authors: Vahid Modanloo, Vali Alimirzaloo, Majid ElyasiAbstract:Micro-stamping process is one of the most cost-effective methods to manufacture metallic bipolar plates (BPPs). This research investigates the forming of titanium thin sheet as a potential candidate for BPPs in proton exchange membrane fuel cell (PEMFC). In this regard, the process was first simulated using finite element (FE) code Abaqus. Afterward, experimental tests were implemented and the validation of the FE model was confirmed using the experimental results. In the simulations, the Corner Radius of the die, draft angle, and friction coefficient at die/sheet interface were selected as variable factors. Forming force and thickness reduction as response functions were evaluated. It is demonstrated that the die Corner Radius has more influence on the maximum punch force compared to the draft angle and friction coefficient. The maximum punch force decreases with increasing the die Corner Radius. On the other hand, in order to have a lower thickness reduction, a high die Corner Radius, higher draft angle, and low friction coefficient are required.
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process parameters optimization in gas blow forming of pin type metal bipolar plates using taguchi and finite element methods
ADMT Journal, 2017Co-Authors: M Moradian, Vahid Modanloo, Ali Doniavi, Vali AlimirzalooAbstract:Metal bipolar plates are the most important parts of the fuel cells and recently these plates are used instead of graphite ones.In the present study, gas blow forming of a pin-type aluminum 5083 bipolar plate has been studied. After the simulation of the process, the FE model has been validated using experimental results. Then, the effects of parameters including maximum pressure of the gas, pressurization profile and Corner Radius of the pin on thinning ratio and forming depth of final part have been investigated. Nine experiments were designed using the Taguchi L9 orthogonal array and the experiments were performed using the FE model. The signal to noise (S/N) ratio and the analysis of variance (ANOVA) techniques were carried out to determine the effective parameters and the contribution of each parameter. The maximum pressure of 1.2 MPa, SP2 pressurization profile and Corner Radius of 0.2 mm lead to the minimum thinning ratio. Also, it was found that to maximize the forming depth, the maximum pressure of 2 MPa, SP1 pressurization profile and Corner Radius of 0.3 mm should be selected. Also, ANOVA analysis showed that the most significant parameters on thinning ratio and forming depth are Corner Radius and maximum pressure, respectively.
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The Optimization of Process Parameters in Gas Blow Forming of Pin-type Metal Bipolar Plates using Taguchi and Finite Element Methods
international journal of advanced design and manufacturing technology, 2017Co-Authors: M Moradian, Vahid Modanloo, Ali Doniavi, Vali AlimirzalooAbstract:Metal bipolar plates are the most important parts of the fuel cells and recently these plates are used instead of graphite ones. In the present study, gas blow forming of a pin-type aluminum 5083 bipolar plate has been studied. After the simulation of the process, the FE model has been validated using experimental results. Then, the effects of parameters including maximum pressure of the gas, pressurization profile and Corner Radius of the pin on thinning ratio and forming depth of final part have been investigated. Nine experiments were designed using the Taguchi L9 orthogonal array and the experiments were performed using the FE model. The signal to noise (S/N) ratio and the analysis of variance (ANOVA) techniques were carried out to determine the effective parameters and the contribution of each parameter. The maximum pressure of 1.2 MPa, SP2 pressurization profile and Corner Radius of 0.2 mm lead to the minimum thinning ratio. Also, it was found that to maximize the forming depth, the maximum pressure of 2 MPa, SP1 pressurization profile and Corner Radius of 0.3 mm should be selected. Also, ANOVA analysis showed that the most significant parameters on thinning ratio and forming depth are Corner Radius and maximum pressure, respectively.
Ajoy Kumar Das - One of the best experts on this subject based on the ideXlab platform.
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A numerical study on effect of Corner Radius and Reynolds number on fluid flow over a square cylinder
Sādhanā, 2017Co-Authors: Prasenjit Dey, Ajoy Kumar DasAbstract:The behaviour of the fluid flowing over a square cylinder with rounded edges subjected to an upstream steady laminar flow was investigated numerically. Here, the commercial CFD software Fluent was used. A two-dimensional steady laminar flow has been investigated numerically at low Reynolds number $$ 5 \leq \hbox{Re} \leq 45 $$ , different Corner radii (r = 0.50, 0.51, 0.54, 0.59, 0.64 and 0.71) and blockage 0.05. The effects of the parameters such as Reynolds number and Corner Radius on the drag and laminar boundary layer have been studied for the first time. The results are shown in the form of drag coefficient, boundary layer and pressure coefficient on the cylinder surface. It is found that the boundary layer thickness and the displacement thickness decrease with decreasing of the Corner Radius for a particular Re and also the boundary layer profile shifted downwards on decreasing Re.
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Analysis of Fluid Flow and Heat Transfer Characteristics Over a Square Cylinder: Effect of Corner Radius and Nanofluid Volume Fraction
Arabian Journal for Science and Engineering, 2017Co-Authors: Prasenjit Dey, Ajoy Kumar DasAbstract:A numerical study of the consequence of the Corner roundness of a square cylinder and nanofluid volume fraction on the warmth transmission and fluid flow phenomenon were studied at low Re ( $${ Re}=100$$ R e = 100 ). The existing nanofluid is made by blending the water with copper nanoparticles, and the blending percentage is in the range of 0–15 % and the Corner Radius is varying from 0.5 D (circle) to 0.71 D (square). The numerical solution is accomplished by a FVM-based code. The fluid flow and the warmth transmission characteristics of the sharp and curved surrounded square chamber were considered with the vorticity, isotherm contours, drag and lift coefficients, local Nusselt number $$(\textit{Nu}_{\mathrm{local}})$$ ( Nu local ) and average Nusselt number $$(\textit{Nu}_{\mathrm{avg}})$$ ( Nu avg ) at various volume fractions and for several Corner roundness. It is found that the heat transfer amount is maximum at $$r=0.51$$ r = 0.51 , whereas at $$r=0.50$$ r = 0.50 , the fluid forces are least for the every volume fractions.
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Optimization of Unsteady Forced Convection over a Rounded Corner Edged Square Cylinder Using GA and PSO
Iranian Journal of Science and Technology Transactions of Mechanical Engineering, 2017Co-Authors: Prasenjit Dey, Ajoy Kumar DasAbstract:The forced convection heat transfer over a rounded Cornered square cylinder has been maximized by optimizing the Corner Radius in two-dimensional unsteady flow regime for the range of Re , 100–180 and Corner Radius ‘ r ’, 0.50–0.71 at Pr = 0.71 (air). The heat transfer characteristics over the rounded Cornered square cylinder are analyzed with the isotherm patterns, local Nusselt number ( Nu _local), average Nusselt number ( Nu _avg) at various Reynolds numbers and for various Corner radii. These numerical results were obtained by solving the two-dimensional unsteady Navier–Stokes equations using a finite volume method-based commercial code FLUENT. The optimization method has been performed by genetic algorithm (GA) and particle swarm optimization (PSO), and it is found that the heat transfer rate of a circular cylinder can be enhanced 9 % by introducing a new cylinder geometry of Corner Radius r = 0.51 and also found that the PSO is more efficient than the GA.
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Analysis of Fluid Flow and Heat Transfer Characteristics Over a Square Cylinder: Effect of Corner Radius and Nanofluid Volume Fraction
Arabian Journal for Science and Engineering, 2016Co-Authors: Prasenjit Dey, Ajoy Kumar DasAbstract:A numerical study of the consequence of the Corner roundness of a square cylinder and nanofluid volume fraction on the warmth transmission and fluid flow phenomenon were studied at low Re (\({ Re}=100\)). The existing nanofluid is made by blending the water with copper nanoparticles, and the blending percentage is in the range of 0–15 % and the Corner Radius is varying from 0.5D (circle) to 0.71D (square). The numerical solution is accomplished by a FVM-based code. The fluid flow and the warmth transmission characteristics of the sharp and curved surrounded square chamber were considered with the vorticity, isotherm contours, drag and lift coefficients, local Nusselt number \((\textit{Nu}_{\mathrm{local}})\) and average Nusselt number \((\textit{Nu}_{\mathrm{avg}})\) at various volume fractions and for several Corner roundness. It is found that the heat transfer amount is maximum at \(r=0.51\), whereas at \(r=0.50\), the fluid forces are least for the every volume fractions.
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Heat Transfer Enhancement Around a Cylinder – A CFD Study of Effect of Corner Radius and Prandtl Number
International Journal of Chemical Reactor Engineering, 2016Co-Authors: Prasenjit Dey, Ajoy Kumar DasAbstract:Abstract An unsteady two-dimensional laminar forced convection heat transfer around a square cylinder with rounded Corner edge is numerically investigated for Prandtl Number, Pr=0.01–1,000 and non-dimensional Corner Radius, r=0.50–0.71 at low Reynolds number, Re=100. The effect of gradual transformation of square cylinder into circular cylinder on heat transfer phenomenon is studied. The lateral sides of the computational domain are kept constant to maintain the blockage as 5 %. A structured non-uniform mesh is used for the computational domain and the Finite Volume Method (FVM) based commercial software Ansys FLUENT is used for numerical simulation. The heat transfer characteristics over the rounded Corner square cylinder are analyzed with the isotherm patterns, local Nusselt number (Nulocal), average Nusselt number (Nuavg) at various Pr and various Corner radii. It is found that the heat transfer rate of a circular cylinder can be enhanced 14 % by introducing a new cylinder geometry of Corner Radius, r=0. 51.
Vahid Modanloo - One of the best experts on this subject based on the ideXlab platform.
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Investigation on Forming of Titanium Bipolar Plates Using Micro-stamping Process
International Journal of Engineering, 2020Co-Authors: Vahid Modanloo, Vali Alimirzaloo, Majid ElyasiAbstract:Micro-stamping process is one of the most cost-effective methods to manufacture metallic bipolar plates (BPPs). This research investigates the forming of titanium thin sheet as a potential candidate for BPPs in proton exchange membrane fuel cell (PEMFC). In this regard, the process was first simulated using finite element (FE) code Abaqus. Afterward, experimental tests were implemented and the validation of the FE model was confirmed using the experimental results. In the simulations, the Corner Radius of the die, draft angle, and friction coefficient at die/sheet interface were selected as variable factors. Forming force and thickness reduction as response functions were evaluated. It is demonstrated that the die Corner Radius has more influence on the maximum punch force compared to the draft angle and friction coefficient. The maximum punch force decreases with increasing the die Corner Radius. On the other hand, in order to have a lower thickness reduction, a high die Corner Radius, higher draft angle, and low friction coefficient are required.
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process parameters optimization in gas blow forming of pin type metal bipolar plates using taguchi and finite element methods
ADMT Journal, 2017Co-Authors: M Moradian, Vahid Modanloo, Ali Doniavi, Vali AlimirzalooAbstract:Metal bipolar plates are the most important parts of the fuel cells and recently these plates are used instead of graphite ones.In the present study, gas blow forming of a pin-type aluminum 5083 bipolar plate has been studied. After the simulation of the process, the FE model has been validated using experimental results. Then, the effects of parameters including maximum pressure of the gas, pressurization profile and Corner Radius of the pin on thinning ratio and forming depth of final part have been investigated. Nine experiments were designed using the Taguchi L9 orthogonal array and the experiments were performed using the FE model. The signal to noise (S/N) ratio and the analysis of variance (ANOVA) techniques were carried out to determine the effective parameters and the contribution of each parameter. The maximum pressure of 1.2 MPa, SP2 pressurization profile and Corner Radius of 0.2 mm lead to the minimum thinning ratio. Also, it was found that to maximize the forming depth, the maximum pressure of 2 MPa, SP1 pressurization profile and Corner Radius of 0.3 mm should be selected. Also, ANOVA analysis showed that the most significant parameters on thinning ratio and forming depth are Corner Radius and maximum pressure, respectively.
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The Optimization of Process Parameters in Gas Blow Forming of Pin-type Metal Bipolar Plates using Taguchi and Finite Element Methods
international journal of advanced design and manufacturing technology, 2017Co-Authors: M Moradian, Vahid Modanloo, Ali Doniavi, Vali AlimirzalooAbstract:Metal bipolar plates are the most important parts of the fuel cells and recently these plates are used instead of graphite ones. In the present study, gas blow forming of a pin-type aluminum 5083 bipolar plate has been studied. After the simulation of the process, the FE model has been validated using experimental results. Then, the effects of parameters including maximum pressure of the gas, pressurization profile and Corner Radius of the pin on thinning ratio and forming depth of final part have been investigated. Nine experiments were designed using the Taguchi L9 orthogonal array and the experiments were performed using the FE model. The signal to noise (S/N) ratio and the analysis of variance (ANOVA) techniques were carried out to determine the effective parameters and the contribution of each parameter. The maximum pressure of 1.2 MPa, SP2 pressurization profile and Corner Radius of 0.2 mm lead to the minimum thinning ratio. Also, it was found that to maximize the forming depth, the maximum pressure of 2 MPa, SP1 pressurization profile and Corner Radius of 0.3 mm should be selected. Also, ANOVA analysis showed that the most significant parameters on thinning ratio and forming depth are Corner Radius and maximum pressure, respectively.
Prasenjit Dey - One of the best experts on this subject based on the ideXlab platform.
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A numerical study on effect of Corner Radius and Reynolds number on fluid flow over a square cylinder
Sādhanā, 2017Co-Authors: Prasenjit Dey, Ajoy Kumar DasAbstract:The behaviour of the fluid flowing over a square cylinder with rounded edges subjected to an upstream steady laminar flow was investigated numerically. Here, the commercial CFD software Fluent was used. A two-dimensional steady laminar flow has been investigated numerically at low Reynolds number $$ 5 \leq \hbox{Re} \leq 45 $$ , different Corner radii (r = 0.50, 0.51, 0.54, 0.59, 0.64 and 0.71) and blockage 0.05. The effects of the parameters such as Reynolds number and Corner Radius on the drag and laminar boundary layer have been studied for the first time. The results are shown in the form of drag coefficient, boundary layer and pressure coefficient on the cylinder surface. It is found that the boundary layer thickness and the displacement thickness decrease with decreasing of the Corner Radius for a particular Re and also the boundary layer profile shifted downwards on decreasing Re.
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Analysis of Fluid Flow and Heat Transfer Characteristics Over a Square Cylinder: Effect of Corner Radius and Nanofluid Volume Fraction
Arabian Journal for Science and Engineering, 2017Co-Authors: Prasenjit Dey, Ajoy Kumar DasAbstract:A numerical study of the consequence of the Corner roundness of a square cylinder and nanofluid volume fraction on the warmth transmission and fluid flow phenomenon were studied at low Re ( $${ Re}=100$$ R e = 100 ). The existing nanofluid is made by blending the water with copper nanoparticles, and the blending percentage is in the range of 0–15 % and the Corner Radius is varying from 0.5 D (circle) to 0.71 D (square). The numerical solution is accomplished by a FVM-based code. The fluid flow and the warmth transmission characteristics of the sharp and curved surrounded square chamber were considered with the vorticity, isotherm contours, drag and lift coefficients, local Nusselt number $$(\textit{Nu}_{\mathrm{local}})$$ ( Nu local ) and average Nusselt number $$(\textit{Nu}_{\mathrm{avg}})$$ ( Nu avg ) at various volume fractions and for several Corner roundness. It is found that the heat transfer amount is maximum at $$r=0.51$$ r = 0.51 , whereas at $$r=0.50$$ r = 0.50 , the fluid forces are least for the every volume fractions.
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Optimization of Unsteady Forced Convection over a Rounded Corner Edged Square Cylinder Using GA and PSO
Iranian Journal of Science and Technology Transactions of Mechanical Engineering, 2017Co-Authors: Prasenjit Dey, Ajoy Kumar DasAbstract:The forced convection heat transfer over a rounded Cornered square cylinder has been maximized by optimizing the Corner Radius in two-dimensional unsteady flow regime for the range of Re , 100–180 and Corner Radius ‘ r ’, 0.50–0.71 at Pr = 0.71 (air). The heat transfer characteristics over the rounded Cornered square cylinder are analyzed with the isotherm patterns, local Nusselt number ( Nu _local), average Nusselt number ( Nu _avg) at various Reynolds numbers and for various Corner radii. These numerical results were obtained by solving the two-dimensional unsteady Navier–Stokes equations using a finite volume method-based commercial code FLUENT. The optimization method has been performed by genetic algorithm (GA) and particle swarm optimization (PSO), and it is found that the heat transfer rate of a circular cylinder can be enhanced 9 % by introducing a new cylinder geometry of Corner Radius r = 0.51 and also found that the PSO is more efficient than the GA.
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Analysis of Fluid Flow and Heat Transfer Characteristics Over a Square Cylinder: Effect of Corner Radius and Nanofluid Volume Fraction
Arabian Journal for Science and Engineering, 2016Co-Authors: Prasenjit Dey, Ajoy Kumar DasAbstract:A numerical study of the consequence of the Corner roundness of a square cylinder and nanofluid volume fraction on the warmth transmission and fluid flow phenomenon were studied at low Re (\({ Re}=100\)). The existing nanofluid is made by blending the water with copper nanoparticles, and the blending percentage is in the range of 0–15 % and the Corner Radius is varying from 0.5D (circle) to 0.71D (square). The numerical solution is accomplished by a FVM-based code. The fluid flow and the warmth transmission characteristics of the sharp and curved surrounded square chamber were considered with the vorticity, isotherm contours, drag and lift coefficients, local Nusselt number \((\textit{Nu}_{\mathrm{local}})\) and average Nusselt number \((\textit{Nu}_{\mathrm{avg}})\) at various volume fractions and for several Corner roundness. It is found that the heat transfer amount is maximum at \(r=0.51\), whereas at \(r=0.50\), the fluid forces are least for the every volume fractions.
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Heat Transfer Enhancement Around a Cylinder – A CFD Study of Effect of Corner Radius and Prandtl Number
International Journal of Chemical Reactor Engineering, 2016Co-Authors: Prasenjit Dey, Ajoy Kumar DasAbstract:Abstract An unsteady two-dimensional laminar forced convection heat transfer around a square cylinder with rounded Corner edge is numerically investigated for Prandtl Number, Pr=0.01–1,000 and non-dimensional Corner Radius, r=0.50–0.71 at low Reynolds number, Re=100. The effect of gradual transformation of square cylinder into circular cylinder on heat transfer phenomenon is studied. The lateral sides of the computational domain are kept constant to maintain the blockage as 5 %. A structured non-uniform mesh is used for the computational domain and the Finite Volume Method (FVM) based commercial software Ansys FLUENT is used for numerical simulation. The heat transfer characteristics over the rounded Corner square cylinder are analyzed with the isotherm patterns, local Nusselt number (Nulocal), average Nusselt number (Nuavg) at various Pr and various Corner radii. It is found that the heat transfer rate of a circular cylinder can be enhanced 14 % by introducing a new cylinder geometry of Corner Radius, r=0. 51.
Majid Elyasi - One of the best experts on this subject based on the ideXlab platform.
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Investigation on Forming of Titanium Bipolar Plates Using Micro-stamping Process
International Journal of Engineering, 2020Co-Authors: Vahid Modanloo, Vali Alimirzaloo, Majid ElyasiAbstract:Micro-stamping process is one of the most cost-effective methods to manufacture metallic bipolar plates (BPPs). This research investigates the forming of titanium thin sheet as a potential candidate for BPPs in proton exchange membrane fuel cell (PEMFC). In this regard, the process was first simulated using finite element (FE) code Abaqus. Afterward, experimental tests were implemented and the validation of the FE model was confirmed using the experimental results. In the simulations, the Corner Radius of the die, draft angle, and friction coefficient at die/sheet interface were selected as variable factors. Forming force and thickness reduction as response functions were evaluated. It is demonstrated that the die Corner Radius has more influence on the maximum punch force compared to the draft angle and friction coefficient. The maximum punch force decreases with increasing the die Corner Radius. On the other hand, in order to have a lower thickness reduction, a high die Corner Radius, higher draft angle, and low friction coefficient are required.