Contents I. Introduction
Fuel cell is type of electrochemical device to transform chemical energy to electrical energy without elimination of Carnot cycle restriction. This type of energy production has higher transformation efficiency and less air pollution because of lower production of NOx and SOx. The most important issue for many countries is to investigate new approach to generate energy to reduce the “”. Fuel cell technology, therefore has became one popular study project. Watkins DS et al., [1] reported that uniform flow could enhance 50% power density. Li X [2] divided flow channels to chessboard, serpentine, parallel, or straight types etc. based on the geometric flowing of the channel. Spurrier et al., [3] redesigned the serpentine type to improve the distribution of reactants and the performance of electricity. Yi and Nguyen [4] used the results calculated by two dimensional and one-way flow methods to analyze the flow rate, diffusion layer and the width of shoulder of channel. They found that the battery performance increased with an increase at the flow rate; while the battery performance decreased with increases at the thickness of electrodes and the width of the flow shoulder. In contrast to that reported by Y and Nguyen, He et al [5] reported that higher flow rate could increase the efficiency of high oxygen transport and expel the water generated during the reaction in the channel to increase the channel numbers and increase the density of electricity. Wang et al., [6] reported the model of two dimensional and two phases and found the mass transportation within the cathode, the characteristic analytic currency, and the distribution of oxygen and water. Gurau et al., [7] developed a mathematical model of two dimensional PEM and found that the air concentration and reaction rate in the flow channel, in the diffusion layer and the inside of catalytic layer, changed depending on the rate of air diffusion and flow.
