NUMERICAL STUDY ON HEAT TRANSFER CHARACTERISTICS OF CORRUGATED TUBE PHASE CHANGE THERMAL ENERGY STORAGE UNIT

Detailed numerical analysis is presented for heat transfer characteristics of charging or discharging process in phase change thermal energy storage unit with inner corrugated tube. The results indicated that the charging or discharging rate of phase change material (PCM) for the case of inner corrugated tube is obviously higher than that in unit with inner plain tube due to the increasing heat transfer surface. The heat transfer rate increase with the increasing mass flow rate. However, when the mass flow rate of heat transfer fluid (HTF) is greater than 0.0315kg/s, the charge and discharge time can not be obviously shorten by increasing mass flow rate. The heat transfer rate between PCM and HTF increases with the increasing of wave amplitude and the decreasing of wavelength.