A Study On Stress And Strain Characteritics Of PEMFC

Proton Exchange Membrane Fuel Cell(PEMFC)is a equipment which can convert chemical energy of fuel directly into electrical energy but does not need the process of combustion, because of its advantage: high energy conversion efficiency, can start on low temperature, no chemical corrosion, high energy density, zero emissions, no pollution, low noise, stable and so on, in recent years, developed rapidly, and has become the most powerful competitor to traditional internal combustion engine, it is the most promising green energy, especially in applications in automotive power, portable power, electronics, etc. But because of the complexity of its work, it is difficult to get detailed distribution of data in its internal by experiment, so that its numerical simulation analysis is particularly important.Firstly, the establishment of a three stack model, based on the finite element method, use ANSYS Workbench software, stack for different clamping and clamping force of different sizes, to simulate the stack assembly. And use Matlab to process the data of simulation results, comparing deformation graph of the stack. The results show that when using the first mode of load with 1MPa-1.5MPa, the performance of stack is optimal; when using the second mode of load with 0.5MPa-1MPa, the performance of stack is optimal; And the second way is better than the first way.Secondly, this paper creates a simplified model of PEMFC, simulate the porosity of gas diffusion layer under different clamping force. The results show that the greater clamping force, the thickness of bipolar plate under gas diffusion layer and porosity is smaller, with an increase clamping force, the thickness of GDL under the rib gradually became thinner, on the other hand, the thickness of GDL under the channel almost remained unchanged.Then, a two-dimensional two-phase flow model was built by fluid analysis software Fluent, to simulate that when through the gas into channel, comparative analysis the gas pressure drop and gas distribution in channel when through different pressure into channel, and so on. Then import the results of pressure distribution to Workbench coupled simulation, comparative analysis strain and contact stress distribution of component, in order to determine the impact of performance of the stack by the assembly load and pressure of gas.Finally, the program of optimize stack assembly is designed, enter the different parameters are calculated can export different results, and then comparative analysis the results of output, can choose the best parameters of stack package and optimal pressure of gas. This program is able to provide guidance and convenience of stack design and stack assembly.