Numerical Simulation of Thermal Energy Storage with Phase Changes Inside Ceramic Tubes
Thermal energy storage technology is key to the continuous generation of electricity in concentrated solar power systems.In this paper,a system simulating a solar-powered generator integrated with a heat storage facility using latent heat of phase change is numerically studied.The system consists of a heater,a thermal energy storage exchanger(TESE),a thermal engine generator and a fan,which are connected in series.Pressurized nitrogen,driven by the fan to pass through the system in a recirculating mode,is used as the heat transfer fluid(HTF).The thermal energy storage exchanger is of shell-and-tube type with phase-change material(PCM)NaCl packed in ceramic tube bundles.The cyclic phase changes and thermal energy storage/release processes were simulated with computational software FLUENT.A 2-dimensional symmetrical geometry was taken and an enthalpy-porosity technique was applied to model the melting/solidification process.The time-dependent inlet and outlet temperatures of HTF,heat flows through tube walls and liquid fraction profile were obtained.Influences of initial temperatures,mass flow rate of HTF and PCM amount were also investigated.In addition,the simulations also show that the TESE could serve as a thermal buffer between heater and engine,smoothing out the temperature oscillation at the entrance of the engine hot-end.
Numerical simulation Thermal energy storage Phase-change Molten salt
Ke Li Wei Dai Zhanghua Wu Ercang Luo
Key Laboratory of Cryogenics,Technical Institute of Physics and Chemistry,Chinese Academy of Science Key Laboratory of Cryogenics,Technical Institute of Physics and Chemistry,Chinese Academy of Science
国际会议
桂林
英文
1-11
2013-07-16（万方平台首次上网日期，不代表论文的发表时间）