| Humid air turbine cycle promises high efficiency,high specific power output, low NOx emissions and good off-design performance. It is one of the new important thermodynamic cycles. Humidifier is a key component of HAT cycle and its performance has significant effect on the general performance of system. A good humidifier should has simple and impact structure,low pressure loss,high efficiency and low driving force in terms of gas turbine cycle.SiC ceramic corrugated packing,which is made of porous material, has high surface area, high porosity and good wetting properties. These excellent performance make it fit for air humidification process. This paper had conducted theoretical and experimental research of the humidifier filled with SiC ceramic corrugated packing, which was used in the air humidification process. The main content of this paper was as follow:(1) Hydrodynamics and heat and mass transfer efficiency of SiC ceramic corrugated packing applied to air humidification process. Dry packing pressure drop,wet packing pressure drop, flooding gas velocity and other important parameters were determined for gas-liquid counter-flow using an air-water system. The pressure drop and flooding velocity of SiC ceramic corrugated packing were compared with TJH corrugated stainless steel packing and SiC ceramic foam packing. The result showed that SiC ceramic foam packing had large pressure drop and very low flooding air velocity. The pressure drop of SiC ceramic corrugated packing was larger than TJH corrugated stainless steel packing, which indicated that the hydrodynamic of the former was not as good as the latter. The mass transfer unit height of SiC ceramic corrugated packing was compared with TJH corrugated stainless steel packing and the six classical packing from the literature.It was noted from the results that the mass transfer unit height which was 1/2-1/3 of the mass transfer unit height of classical packing.So the SiC ceramic corrugated packing had good heat and mass transfer performance.If it were used in the air humidification process, the amount of packing can be reduced, which can make the humidifier be lower and be impact.(2).Thermal performance study of packed humidifier. A pressurized packed humidifier was built. The SiC ceramic corrugated packing was used in the humidifier. The air humidification process was investigated in a wide operation range. The role of the ratio of water and air mass rate, the inlet water temperature, the operation pressure and other parameters in determining the thermodynamic performance of the humidifier was analyzed. Exergy analysis method was used to study the performance of the humidifier. Relationship between exergy and parameters such as inlet air temperature, the ratio of water and air mass rate and inlet water temperature was obtained. A non-dimensional correlation about air outlet temperature and a non-dimensional correlation about mass transfer coefficient of the SiC ceramic foam corrugated were obtained based experimental data.(3). A theoretical model of humidifier. The heat and mass transfer in the humidifier was analyzed. A theoretical model of humidifier was built based on mass conservation equation, energy conservation equation and heat and mass transfer equation. The model is validated against experimental data. The model was used to evaluate the performance of humidifier. The distribution of water and air parameters in the packing was acquired.What is more, the exergy analysis method was used to investigate the exergy distribution and exergy destruction distribution in the tower. It was noted from the results that air humidification process was dominated by the mass transfer between water and air. Air extracted exergy from water mainly by evaporation. The exergy destruction at the bottom of the tower is large.Many measures should be taken to reduce the exergy loss at the bottom in order to improve the performance of humidifier.
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