| Among them,phase change heat storage technology is popular because of its high energy storage density.Based on the heating system of air heating unit,the temperature change and melting law of the phase change material in the phase change heat storage device,as well as the economy of the phase change heat storage system are studied by means of experiments and numerical simulation of small scale system.1)Based on the temperature of the heating water in the heating system of the air heating unit,polyethylene resin was selected as the phase change material for experimental research,and a layered phase change heat storage device with fins was designed to increase the heat transfer area.It is found that the polyethylene resin in the phase change heat storage device has the phenomenon of overheating at the top and not melting at the bottom.The inlet temperature of 70 ℃ is 31% higher than that of 65 ℃,and the inlet mass flow rate of 1.2 kg/s is 18% higher than that of 0.8kg/s.2)An experimental platform which can monitor the temperature change of PCM in real time and adjust the temperature and flow rate was built for experimental exploration;The Boussinesq hypothesis was adopted in Fluent to verify the temperature change and melting rule of polyethylene resin in the phase change heat storage device by numerical simulation with the same boundary conditions as the experiment.3)Taking Huangdi Town project as the standard,the economy of the heating system with or without phase change heat storage system in the air heating unit is analyzed.Taking Huangdi Town project as the standard,the phase change heat storage system needs to invest 155000 yuan,and the investment can be recovered after 1579 days of operation(9.5 heating seasons).Figure 57;Table 8;Reference 54... |
