Phase Change Heat Transfer Characteristics Of Heat Exchanger And Its Application Research

This paper, saving up the spare and discrete energy by using energy storage technology,to realize the time and space transfer of energy utilization.By using the research methods of experiment and numerical simulation,investigated the characteris-tics of phase change heat exchanger about heat transfer and energy storage,studied the the energy storage process of heat exchanger and phase change law of PCM,raised the empirical formula of phase change energy storage heat transfer about the biggest heat storage.As follows is the main research contents and conclusions:1.Select several kinds of energy storage materials for this topic temperature requirements,through the experiment method of heating and cooling,Determine the phase change temperature uniformity, super-cooling degree, heat transfer of PCM, thought the phase change wax is the most suitable PCM,the phase transition temperature is 30 ℃,isotropic heat transfer, thermal stability, super-cooling degree is less than 1℃.2.According to the research method of the numerical simulation, using gambit established the heat transfer model of the phase change heat storage unit, and by using fluent software simulated the heat transfer process of phase change unit, calculated the curve about the relationship between the phase interface position,temperature distribution and time in melting and solidification process of PCM.Results show,that Phase change thermal storage unit has the highest heat transfer and phase change energy storage efficiency when the liquid rate of maximum,then Scope of phase transformation range is regarded as the best reservoir of PCM, the best reservoir range of inner diameter is about 16.6 mm of the heat storage unit,That is to say, PCM phase transformation range is 2.3 mm.3.Using phase change wax as energy storage materials produced a kind of phase change heat exchanger, experimental studied phase change heat storag proper-ties and heat transfer process of PCM.The experiment proved that the most suitable flow rate is 0.00047 m3 / s of the energy storage heat exchanger, and is strongly influenced by the heat source temperature, with the biggest heat storage when the temperature is 55℃, under the condition of ignoring heat loss of energy storage efficiency up to 22%, maximum heat storage is 25.821 KJ 85 minutes later, and fitting out the access to the biggest store heat and gas heat exchanger and the function relation between the temperature of phase change heat storage medium f=808.6x+6.9y.It is concluded that PCM has better filling in the range of 2 mm to 5 mm of the heat exchanger,Layout spacing is 4 mm to 10 mm of the tubulation.