Study On Regeneration Process Of Heat Source Type Solution In Air Conditioning System With Heat And Moisture

There are many problems in conventional air conditioning system such as the waste of reheat, poor air quality, indoor terminal devices’ poor adaptability to the ratio of heat load to moisture load and so on. So based on the combine of solution dehumidification cycle and the refrigerating cycle of vapor-compression, the synthetical utilization of solar energy storage and solution energy storage and the segmented use of condensing heat of vapor compression refrigeration system, an air conditioning system that handling with heat and humidity independently and utilizing the classified condensing heat is proposed. The system synthetically utilizes solar energy and the condensing heat of refrigeration system as the power source. The waste heat of condensing is used with classification and the solar energy storage and solution energy storage are combined. The high efficient compensation of the regeneration heat in the air conditioning system that handling with heat and humidity independently is also solved. The system is energy saving. For the latent heat storage is used to improve the energy efficiency and system stability, the sustainable development of energy utilization is realized.The coefficient of performance is improved because of the increased evaporating temperature in the refrigeration cycle in summer. All heat of the outdoor moist air is made full use of and is used as the low-temperature heat source of the evaporator of heat pump in winter. So the coefficient of performance is improved and the frosting problem of the outdoor unit is effectively improved. The paper does the thermodynamic calculation of the system in two modes:summer and winter. In this calculation, the influence of the outdoor air’s state parameters, the indoor air’s state parameters, the ratio of fresh air and the change of the ratio of indoor sensible heat load on the coefficient of performance is studied.The theoretical model of the contranatant reactivation process is built based on the mechanism of the heat and mass transfer in regeneration process. In the iterative process of the governing equation, the Gauss Seidel method and the logarithmic average enthalpy humidity method is combined to calculate NTU and the state parameters of the outlet of air and solution. Therefore, the complex process of getting the initial NTU from experiments is avoided. The method can provide the theoretical foundation for the design and calculation from now on. The values calculated by simulation and the values got from the experiments are compared and the relative error is within 10%. It was found that the theoretical model is applicable to the process of regeneration of air heating and solution heating.An experimental platform of a solution regeneration system is built to analyze the influences of the temperature and humidity of the solution and the air on regeneration performance in the winter condition, and to carry out comparative experiments on the heat and substance conduction performance of the regeneration systems of the adiabatic type and the internal heating type. The result of the experiments show that it is all profitable to increasing the regenerate amount in the regeneration processes to increase the temperature and the humidity of the solution and the air. In the process of the air heating regeneration, while the air temperature and flow increase, the thermal efficiency of regeneration raises first and drop afterward. In the process of the heating regeneration of the solution, increasing the solution flow helps increasing the regenerative thermal efficiency, while the regenerative thermal efficiency declines after the import temperature of the solution is raised. The regenerative amount and the regenerative thermal efficiency in the process of the internal heated regeneration type are both higher than those of the adiabatic type, and those can always maintain in a relatively high level.At the same time, an experimental study is carried out about the influences of sensible heat and latent heat of condensation process on the solution regeneration process. The results show that either by adjusting temperature or the flow of the solution, regenerative amount is always increasing with the reduction process of the ratio of the sensible heat and latent heat of condensation. Adjusting the solution temperature to change the sensible heat of condensation is prior to adjusting the solution flow, and the regenerative thermal efficiency is higher because of that. Therefore, during the subsection utilization process of the heat condensation, to raise the temperature of the regenerator import solution through increasing the heat of the solution in the heat exchanger is more profitable to the process of regeneration. All these will improve the energy utilization efficiency.