Abstract:

In order to explore heat transfer mechanism of cross-flow rotating packed bed, heat transfer performance of cross-flow rotating packed bed with wire mesh packing and random packing was investigated by using hot air-ammonia as heat transfer system. And the effects of inlet temperature T, high gravity factor β, liquid spray density q and gas velocity u on the heat transfer performance of cross-flow rotating packed bed were investigated. The research results showed that volumetric mass transfer coefficient of gas phase k_ya_e and volumetric heat transfer coefficient (Ua)_sincreased with the increase of inlet temperature, high gravity factor, gas velocity and liquid spray density. Heat transfer efficiency ε and heat transfer area A also increased with the increase of high gravity factor, gas velocity and liquid spray density and the heat transfer coefficient K was almost unchanged. The results revealed that the mechanism of the cross-flow rotating packed bed to enhance gas-liquid direct heat transfer was to increase the heat transfer area to improve the volumetric heat transfer coefficient, rather than to significantly increase the heat transfer coefficient. Under the same conditions, k_ya_e and (Ua)_s are 1.09—1.63 times and 1.24—3.53 times that of random packing with wire mesh as filler, respectively.

Key words: cross-flow rotating packed bed, volumetric mass transfer coefficient of gas phase, volumetric heat transfer coefficient, heat transfer efficiency, heat transfer coefficient, heat transfer area

摘要：

为了研究错流旋转填料床的质、热同传性能，采用热空气-氨水体系，考察了进气温度T、超重力因子β、液体喷淋密度q和气速u对错流旋转填料床传热性能的影响，在相同实验条件下对比了丝网填料和乱堆填料的传热性能。研究结果表明：气相体积传质系数k_ya_e、体积传热系数(Ua)_s随进气温度、超重力因子、气速、液体喷淋密度的增大而增大；传热效率ε、传热面积A随超重力因子、气速、液体喷淋密度的增大而增大；传热系数K随超重力因子、气速、液体喷淋密度的增大几乎不变，从而揭示了错流旋转填料床强化气液直接传热的机理是通过提高传热面积进而提高体积传热系数，而不是显著提高传热系数。在相同条件下，以丝网为填料时k_ya_e和(Ua)_s分别是乱堆填料的1.09~1.63倍和1.24~3.53倍。

关键词: 错流旋转填料床, 气相体积传质系数, 体积传热系数, 传热效率, 传热系数, 传热面积