Free Heat and Mass Transfer in a Porous Enclosure with Side Vents

被引:16
作者
Zhao, Fu-Yun [1 ]
Liu, Di [1 ,2 ]
Wang, Han-Qing [1 ,3 ]
Kou, Guang-Xiao [1 ]
Tang, Guang-Fa [2 ]
机构
[1] Hunan Univ Technol, Sch Civil Engn, Zhuzhou 412007, Hunan, Peoples R China
[2] Hunan Univ, Coll Civil Engn, Changsha 410082, Hunan, Peoples R China
[3] Cent S Univ, Sch Energy Sci & Engn, Changsha, Hunan, Peoples R China
关键词
CFD; Heat and mass transfer; Porous media; DIFFUSIVE NATURAL-CONVECTION; SQUARE OPEN CAVITY; AIR-FLOW; BOUNDARY; POROSITY; DRYER; MEDIA; LAYER; OSCILLATIONS; PERFORMANCE;
D O I
10.1080/07373937.2010.482701
中图分类号
TQ [化学工业];
学科分类号
0817 ;
摘要
Free heat and mass transfer during drying in a porous enclosure with free vents has been investigated numerically. Enclosed moist air interacts with the surrounding air through freely vented ports situated on both sides perpendicular to the heated wall. Air, heat, and moisture transport structures are visualized respectively by streamlines, heat lines, and mass lines. Effects of thermal Rayleigh number, Darcy number, vent location, and enclosure inclination on the convective heat/moisture transfer rate and volume flow rate across this enclosure are discussed. For each case, partially enclosed fluid flow undergoes different phases, increasing with buoyancy ratio; that is, heat transfer-driven flow, heat- and moisture-aided flow, and moisture transfer-dominated flow. Numerical results demonstrate that the convective heat and moisture transport patterns and transport rates greatly depend on thermal Rayleigh number, properties of porous medium, and enclosure inclination. Practices for enhancing heat and moisture transfer have been suggested for drying processes.
引用
收藏
页码:91 / 104
页数:14
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