具有电介质核心多孔介质微波冷冻干燥过程耦合传热传质数值研究.pdf

19 2 No.2 Vol.19 2005 4 Journal of Chemical Engineering of Chinese Universities Apr. 2005 1003-9015(2005)02-0181-06 1,2 1 2 1 1 1 , , , , , (1. , 100083 2. , ) 1.0 1.5 2.0 2.5mm 8%19%33%48% TQ028.23 TQ028.677 A Numerical Study on Conjugate Heat and Mass Transfer Process within Porous Media with Dielectric Cores during Microwave Freeze Drying 1,2 1 2 1 1 1 WU Hong-wei , TAO Zhi , CHEN Guo-hua , DENG Hong-wu , XU Guo-qiang , DING Shui-ting (1. School of Jet Propulsion, The Beijing University of Aeronautics and Astronautics, Beijing 100083, China; 2. Department of Chemical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China) Abstract Microwave freeze drying of porous media with dielectric cores was studied numerically. The sets of transient governing equations developed for the conjugate heat and mass transfer process was derived and solved with variable time-step finite volume method. Numerical results show that two sublimation fronts do exist within the porous media, and this is a new phenomenon associated with dielectric core. The two sublimation fronts model proposed can successfully simulate this drying process of porous media with dielectric cores. A dramatic drying time saving could be obtained with proper