TY - JOUR
A2 - Zhang, Zhijun
AU - Zhang, Shiwei
AU - Liu, Jun
PY - 2012
DA - 2012/07/24
TI - Distribution of Vapor Pressure in the Vacuum Freeze-Drying Equipment
SP - 921254
VL - 2012
AB - In the big vacuum freeze-drying equipment, the drying rate of materials is uneven at different positions. This phenomenon can be explained by the uneven distribution of vapor pressure in chamber during the freeze-drying process. In this paper, a mathematical model is developed to describe the vapor flow in the passageways either between material plates and in the channel between plate groups. The distribution of vapor pressure along flow passageway is given. Two characteristic factors of passageways are defined to express the effects of structural and process parameters on vapor pressure distribution. The affecting factors and their actions are quantitatively discussed in detail. Two examples are calculated and analyzed. The analysis method and the conclusions are useful to estimate the difference of material drying rate at different parts in equipment and to direct the choice of structural and process parameters.
SN - 1024-123X
UR - https://doi.org/10.1155/2012/921254
DO - 10.1155/2012/921254
JF - Mathematical Problems in Engineering
PB - Hindawi Publishing Corporation
KW -
ER -