基于压力速度耦合算法的PEMFC电堆空气分布

Air distribution in PEMFC stack based on pressure-velocity coupling algorithm

利用燃料电池流道简化方法和压力速度耦合算法,研究了U形和Z形2种结构的电堆空气分布,以及歧管宽度和燃料电池单体数量对空气分布的影响.结果表明:由于U形和Z形结构的歧管出口压力分布不同,导致2种结构的空气分布不同,Z形结构的空气分布要比U形结构好;歧管尺寸增大时,空气分布的均匀性得到了明显改善,当空气分布差异不大时,再增加歧管尺寸,效果会降低,且增加电堆成本;在电池数量增加、歧管横截面积不变时,空气分布的均匀性会明显变差,尤其是U形结构;当电池数量为30个、歧管宽度为20 mm时,空气分布较均匀;当电池数量为50个时,歧管宽度需要达到30 mm,空气分布才较均匀.

Using the simplified fuel cell flow field and pressure-velocity coupling algorithm,the air distributions of U-type and Z-type fuel cell stack were investigated,and the effects of manifold width and fuel cell number on the air distribution were analyzed.The results show that the fluid distributions of Z-type is better than that of U-type because of the different outlet pressure distribution of the Z-type and the U-type.The uniformity of air distribution is greatly improved when the size of manifold is increase.The effect of increasing the manifold size is not obvious and can increase the cost when the air distribution difference is small.When the number of fuel cells is increased without changing the manifold size,the uniformity of the air distribution become worse,especially for the U-type.The air distribution is uniform when the number of fuel cells is 30 with the manifold width of 20 mm.The width of manifold should be increased to 30 mm for obtaining uniform air distribution when the number of fuel cells is 50.