膜法除湿组件的热量、质量积耗散性能研究

Performance Study on Membrane-Based Dehumidification Component With Heat and Mass Entransy Dissipation

建立了错流中空纤维膜液体除湿的二维传热、传质数学模型。引入热阻因子与湿阻因子来衡量溶液除湿过程中热湿传递的不可逆性。比较了不同空气-溶液流量比与空气-溶液进口状态的热阻、湿阻因子,得到空气-溶液流量比为1:1时,热湿传递的不可逆性较小。由于错流除湿器偏离平衡逆流传热传质形式,最小热阻、湿阻因子不在溶液进口状态等浓度线上,最小热阻在偏离等浓度线使得空气与溶液的温差更大的点,最小湿阻因子在偏离等浓度线使得空气与溶液的水蒸气分压差更大的点。

A two dimension cross-flow hollow fiber membrane heat and mass transfer module was investigated.Thermal and mass resistance factors were introduced to evaluate the heat and mass transfer irreversibility in liquid dehumidification.The factors under different air-desiccant flow ratio and inlet states were compared.As air flow equals to desiccant flow,factors are small.Unlike the balanced countercurrent arrangement,the minimum thermal and mass resistance factors for cross flow are not on the iso-concentration lines from the inlet desiccant point.The former is at the point with larger temperature difference from iso-concentration line,while the latter one is at the point with a larger partial vapor pressure difference from the iso-concentration line.