| HAT(Humid Air Turbine)technology, initially proposed by Rao, can greatly enhance gas turbine performance, especially with regard to efficiency and increasing specific work output. Such an enhancement can be achieved by introducing an innovative component into the power plant system layout: the saturator. This component, which acts as a pressurized humidification tower, permits the introduction of water under boiling point into the compressed air steam with minimal exergy losses. The saturator is so important that we should do further study about it. Currently, studies on HAT cycle mainly focus on the whole performance such as efficiency, specific work output. But there is not enough research on the key unit (saturator), and it is mainly about the after-cooling saturator. There is less study on the no-after-cooling saturator. So on the basis of experiment researches and theory caculations, this paper analyses mass and heat transfer in saturator without after-cooling system and compares the differences with the after-cooling saturator. This is almost the first time in China to introduce the no-after-cooling saturator.This paper studies, both theoretically and experimentally, on the no-after-cooling saturator. Its main character lies in there is no after-cooling system in the HAT Cycle. On the experiment part,a saturator test rig is designed to study the performance of no-after-cooling system. Firstly, according to the already built PDA test rig, the author studies the droplet diameter of HH series nozzle and Spray series nozzle, and its effect to the performance of the saturator. It is found through experimental data that the size of droplet diameter has bigger impact on spray saturator. And there is less pressure drop in spray saturator than packed saturator. Then the effect of inlet air temperature is analyzed and the ratio of water flow to air flux has large effect on the performance of the saturator according to the experiment. The performance parameters include the outlet water and air temperature, the humidity of the outlet air, the mass flow of air and water. Then, according to the experiment result, the humidity that we can reach is 0.034Kg/Kg,and the related humidity is more than 96%. So this humidity can fit us well. At last, it can be found that with the increase of inlet air temperature there is a humidity increase from the saturator's performance parameters. But with the increase of ratio of water flow to air flux, there is a decrease of air humidity. Because with that ratio increase, there is lower outlet air temperature, and the air is almost reach ? in=1, so the humidity is the function of temperature.On theory, one dimension theoretical model has been built on the basis of water and vapor's latest equation IAPWS IF-97 and real-state gas equation of air, which is applicable for high pressure condition. According to the model, the equations are built and dispersed according to improving Euler method. Then a C++ program is made to analyze the heat and mass transfer in saturator. With the analysis of critical parameters such as inlet water temperature (Twin), the ratio of water flow to air flux (λ), general mass transfer coefficient (Ω), all the law curves are depicted. The inlet air temperature has large impact on the saturator performance, and at the same time the inlet water temperature has large impact on the traditional HAT's saturator. So from these analyses we can get that the output humidity can be easily controlled by the inlet temperature.With comparison to after-cooling saturator, it can be found that no-after-cooling saturator is easier to be affected by the inlet air temperature, but after-cooling saturator is prone to the inlet water temperature. From the theory calculation, we can get that the saturator without after-cooling system can reach more humidity when there is a same temperature increase, but it need more conditions to satisfy the humidity.
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