Condensation of humid air along a vertical plate was numerically investigated, with the mathematical model built on the full boundary layer equations and the film-wise condensation assumption. The velocity, heat and m...Condensation of humid air along a vertical plate was numerically investigated, with the mathematical model built on the full boundary layer equations and the film-wise condensation assumption. The velocity, heat and mass transfer characteristics at the gas-liquid interface were numerical analyzed and the results indicated that it was not reasonable to neglect the condensate film from the point of its thickness only. The condensate film thickness, interface temperature drop and the interface tangential velocity affect the physical fields weakly. However, the subcooling and the interface normal velocity were important factors to be considered before the simplification was made. For higher wall temperature, the advective mass transfer contributed much to the total mass transfer. Therefore, the boundary conditions were the key to judge the rationality of neglecting the condensate film for numerical solutions. The numerical results were checked by comparing with experiments and correlations.展开更多
The rotating packed bed （RPB） with split packing is a novel gas-liquid contactor, which intensifies the mass transfer processes controlled by gas-side resistance. To assess its efficacy, the mass transfer characteri...The rotating packed bed （RPB） with split packing is a novel gas-liquid contactor, which intensifies the mass transfer processes controlled by gas-side resistance. To assess its efficacy, the mass transfer characteristics with adjacent rings in counter-rotation and co-rotation modes in a split packing RPB were studied experimentally. The physical absorption system NH3-H2O was used for characterizing the gas volumetric mass transfer coeffi- cient （kyae） and the effective inteffacial area （ae） was determined by chemical absorption in the CO2-NaOH sys- tem. The variation in kyae and ae with the operating conditions is also investigated. The experimental results indicated that kyae and ae for counter-rotation of the adjacent packing rings in the split packing RPB were higher than those for co-rotation, and both counter-rotation and co-rotation of the split packing RPB were superior over conventional RPBs under the similar ooerating conditions.展开更多
This article describes the experimental results obtained by the solar distiller by specifying the radiative properties of materials, the analysis of various types of losses in the system and the establishment of the e...This article describes the experimental results obtained by the solar distiller by specifying the radiative properties of materials, the analysis of various types of losses in the system and the establishment of the energy assessment of the system being the main question to consider. The experiment was undertaken in Tlemcen-Algeria by working out a solar distiller in order to measure the various temperatures of the system. Salt was added to study the negotiable effect of the salinity of water on solar distillation and it is noted that the production of distilled water decreases with salinity. The distiller is forwarded to a constant global solar flow. Experimental results obtained in heat transfer of natural convection in the pure and simultaneous heat and mass transfer, proven that these phenomena are in the boundary layer. This enables people to admit that the existence of a stagnant zone inside of distiller is called the ＂buffer zones＂.展开更多
基金Supported by the National Basic Research Program of China （2011CB706904） and Beijing Natural Science Foundation （3071001）
文摘Condensation of humid air along a vertical plate was numerically investigated, with the mathematical model built on the full boundary layer equations and the film-wise condensation assumption. The velocity, heat and mass transfer characteristics at the gas-liquid interface were numerical analyzed and the results indicated that it was not reasonable to neglect the condensate film from the point of its thickness only. The condensate film thickness, interface temperature drop and the interface tangential velocity affect the physical fields weakly. However, the subcooling and the interface normal velocity were important factors to be considered before the simplification was made. For higher wall temperature, the advective mass transfer contributed much to the total mass transfer. Therefore, the boundary conditions were the key to judge the rationality of neglecting the condensate film for numerical solutions. The numerical results were checked by comparing with experiments and correlations.
基金the National Natural Science Foundation of China(21376229,21206153)
文摘The rotating packed bed （RPB） with split packing is a novel gas-liquid contactor, which intensifies the mass transfer processes controlled by gas-side resistance. To assess its efficacy, the mass transfer characteristics with adjacent rings in counter-rotation and co-rotation modes in a split packing RPB were studied experimentally. The physical absorption system NH3-H2O was used for characterizing the gas volumetric mass transfer coeffi- cient （kyae） and the effective inteffacial area （ae） was determined by chemical absorption in the CO2-NaOH sys- tem. The variation in kyae and ae with the operating conditions is also investigated. The experimental results indicated that kyae and ae for counter-rotation of the adjacent packing rings in the split packing RPB were higher than those for co-rotation, and both counter-rotation and co-rotation of the split packing RPB were superior over conventional RPBs under the similar ooerating conditions.
文摘This article describes the experimental results obtained by the solar distiller by specifying the radiative properties of materials, the analysis of various types of losses in the system and the establishment of the energy assessment of the system being the main question to consider. The experiment was undertaken in Tlemcen-Algeria by working out a solar distiller in order to measure the various temperatures of the system. Salt was added to study the negotiable effect of the salinity of water on solar distillation and it is noted that the production of distilled water decreases with salinity. The distiller is forwarded to a constant global solar flow. Experimental results obtained in heat transfer of natural convection in the pure and simultaneous heat and mass transfer, proven that these phenomena are in the boundary layer. This enables people to admit that the existence of a stagnant zone inside of distiller is called the ＂buffer zones＂.
