膜加湿器热质交换过程的理论分析

膜加湿器是保证质子交换膜燃料电池(PEMFC)正常高效运行的重要组成部分.以燃料电池的板式膜加湿器为研究对象,根据热质交换原理对膜加湿器的传热传质过程进行了理论计算,分析了空气质量流量、膜内加湿侧进口温度和膜内加湿侧进口湿度对传热传质过程的影响.在传热方面:当空气质量流量不同时,随着膜内加湿侧进口温度的变化,膜内的热流量变化趋势不一致;当膜内加湿侧进口相对湿度为95%时,随着空气质量流量的变化,膜内热流量变化不大.在传质方面:当加湿侧进口相对湿度不变时,膜中水传输速率随着空气质量流量的增大而减小;当空气质量流量不变时,膜中水传输速率随着加湿侧进口相对湿度的增大而增大.

Theoretical analysis on the process of heat and mass transfer in the membrane humidifier

Membrane humidifier is an important part to ensure the proton exchange membrane fuel cell run normally and efficiently.The effects of the air mass flow rate,the inlet temperature on the humidifying side,and the inlet humidity on the process of heat and mass transfer in the membrane humidifier were analyzed in this study.The experimental results indicated that the heat flow within the membrane had different trends with the inlet temperature on the humidifying side when the air mass flow rate changed.When the inlet relative humidity on the humidifying side was 95%,the heat flow changed little within the membrane with the variation of the air mass flow rate.The water transfer rate within the membrane decreases with the increase of the air mass flow rate when the inlet relative humidity on the humidifying side was constant.At the constant air mass flow rate,the water transfer rate in the membrane increased with the increase of inlet relative humidity on the humidifying side.