Numerical Simulation And Experiment Research On Intersectant Flow Field Of Proton Exchange Membrane Fuel Cell

Fuel cell is the most promising clean energy and considered to be the optimal substituted energy for traditional ones.Among various kinds of fuel cells,proton exchange membrane fuel cell draws more attention because of its advantages such as small volume,fast start up,high transfer efficiency and low operation temperature.Bipolar plate is one of the key components of PEMFC.The surface structure of bipolar plate may have an important influent on the comprehensive performance of the fuel cells.This paper design a kind of intersectant channel which has multiple branches and multiple intersects according to orderly-fixation process of work piece's surface microstructure.Intention of this design is to improve uniformity of gas distribution and decrease global flow resistance and pressure drop thus consumption of pumping power while fuel cell is saved and enhance output efficiency of fuel cell.Main contents of the paper are:(1)Based on orderly-fixation grinding process of work piece's surface microstructure and Murray law,Fractal geometry theory,present a intersectant flow field.3D models for PEMFCs with intersectant channel are presented under the assumptions of steady and isothermal conditions.Numerical results show that PEMFC with intersectant channel has better performance than serpentine channel.(2)To enhance the comprehensive performance of PEMFCs with intersectant channel,impact of two key geometrical parameters on performance of intersectant channel is investigated to gain optimal geometrical parameter values.The two key geometrical parameters include porosity and channel heigh.Numerical results suggest that fuel cell with channel depth 0.3mm and porosity 0.5 shows the best comprehensive performance.(3)In order to analyze the influent of intersectant channel to the performance of fuel cells,a performance test device of PEMFCs was constructed.Experimental study summarized the optimal operational parameters of PEMFCs.Based on it,carry out a comparative analysis between intersectant flow field and serpentine flow field to the influence of fuel cell.The results show that the comprehensive performance of PEMFC with intersectant channel are beyond serpentine channel.What's more,in the range of allowable error,experimental studies and numerical results anastomose well.This paper designs a kind of intersectant channel for PEMFCs by conducting numerical simulation and experimental study.Results of present work are instructive for design and manufacturing of PEMFCs.