| Air source heat pump was widely used, however, its shortcomings were the poorlow-temperature adaptability and frosting at the outdoor heat exchanger. Solarenergy as a renewable low heat source heat pump was very attractive. Solar energyhad the incomparable advantages, but it had disadvantages of low energy density,intermittent, high cost of collecting and converting equipment. Therefore, in orderto solve this problem, improving air source heat pump and solar energy low-temperature performance, a phase change energy storage used to change the energyof time, making up the solar energy low heat source of instability and intermittentproblems, the thesis puts forward Heat Pump Integrated System with Triple-sleeveEnergy Storage Exchangers (HPISTRESE). This paper studies the new systemdynamic characteristics, the main research contents are as follows:Core part of the HPISTRESE—triple-sleeve energy storage exchanger (TRESE)was prepared and experimental setup for HPISTESE was built. The test data can becollected automatically and dynamic experimental study on cool storage mode, heatstorage simultaneous stored energy heat pump heating mode, stored energy heatpump heating mode and cool release mode were carried out. The experimentalresults show that, in the integrated system COP of heat storage simultaneous storedenergy heat pump heating mode was highest, energy storage heat pump heatingmode was next, and cool storage mode had the minimum value. Cool energyreleasing rate in cool release process changed dramatically, and dischargingstability was slightly. Experiments of the heat storage mode show that the triple-sleeve energy storage exchanger has high heat storage rate.Mathematical model of triple-sleeve energy storage exchanger unit was established,based on the distribution parameter method dynamic simulation mode was set up.Heat transfer characteristics of the energy storage heat exchanger unit wereanalyzed. The results show that triple-sleeve energy storage exchanger unit havegood heat transfer effect, and the influence of different factors on the heat transfercharacteristics were analyzed. The analysis supplied theoretical basis for heattransfer enhancement as well as optimal design of triple-sleeve energy storageexchanger.Study on the analysis of operating characteristics and mechanism of solar and airsource heat pump integrated system with triple-sleeve energy storage exchangers,and experimental system dynamics model was set up. Combining theory and experiment, and the results of comparing the experimental data and numericalsimulation results indicate that the model can well reflect the physical process ofsystem operation modes.Based on the validated mathematical model, the influence factors of the water flowmass rate, water temperature and heat storage structures on the operatingcharacteristics of different modes were anaylized. The analysis results suggestedthat reducing energy storage unit quantity of triple-sleeve energy storage exchanger,the operating performance of cool storage mode and heat storage simultaneousstored energy heat pump heating mode declined quickly. Increasing water flowmass rate and water temperature can improve performance of heat storagesimultaneous stored energy heat pump heating mode. In the cool release mode,reducing water flow mass rate can improve cool energy releasing stability. Resultsfor matching the energy storage heat exchanger and integrated system supplied thetheory basis.The yearly operating performance of the integrated system was carried out forcomprehensive evaluation. Firstly, selection and design calculation of the integratedsystem was carried out. The operating conditions of different modes were analyzed.Secondly, the yearly operation performance of integrated system were studied, andcompared with the conventional air source heat pump system with the annualenergy consumption and operation cost. The results show that the integrated systemhas good energy-saving effect, however, constrained by the price of phase changematerial investment recovery period of integrated system is long.The research work in this paper comprehensive grasps the novel solar and airsource heat pump integrated system with triple-sleeve energy storage exchangers,and the study results supplied theory basis and technical reserve for the integratedsystem optimal design and construction load matching. In addition, the thesisprovides new ideas for comprehensive energy-saving and ecological energyapplication. |
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