High-temperature Phase Change Material (PCM) is used as a thermal storage medium of a heat-pipe receiver in an advanced solar dynamic system.With both void cavity and natural convection considered,thermal performance ...High-temperature Phase Change Material (PCM) is used as a thermal storage medium of a heat-pipe receiver in an advanced solar dynamic system.With both void cavity and natural convection considered,thermal performance of the heat-pipe receiver is numerically analyzed under gravity.The results indicate that the PCM contained in the integrated heat pipe performs an averaging function of heat loadings.The thermal performance of the heat-pipe receiver is stable and reliable.When a heating cycle is stable,the temperature fluctuations both on heat-pipe wall and in PCM canister remain less than 13 K throughout a sunlight and eclipse cycle.The utility of PCM is essentially improved.The maximum melting ratio of PCM is 92%.Under gravity,PCM melts more quickly with the effect of natural convection.Natural convection accelerates the process of phase changes.Numerical results are compared with the experimental results concerned.The accuracy of numerical model under gravity is verified.The experiment for the PCM canister on the ground can be well prepared with our numerical simulation.展开更多
Based on theoretical analysis of PCM(Phase Change Material) solidification process, the model of improved void cavity distribution tending to high temperature region is established. Numerical results are compared with...Based on theoretical analysis of PCM(Phase Change Material) solidification process, the model of improved void cavity distribution tending to high temperature region is established. Numerical results are compared with NASA(National Aeronautics and Space Administration) results. Analysis results show that the outer wall temperature, the melting ratio of PCM and the temperature gradient of PCM canister, have great difference in different void cavity distribution. The form of void distribution has a great effect on the process of phase change. Based on simulation results under the model of improved void cavity distribution, phase change heat transfer process in thermal storage container is analyzed. The main goal of the improved designing for PCM canister is to take measures in reducing the concentration distribution of void cavity by adding some foam metal into phase change material.展开更多
文摘High-temperature Phase Change Material (PCM) is used as a thermal storage medium of a heat-pipe receiver in an advanced solar dynamic system.With both void cavity and natural convection considered,thermal performance of the heat-pipe receiver is numerically analyzed under gravity.The results indicate that the PCM contained in the integrated heat pipe performs an averaging function of heat loadings.The thermal performance of the heat-pipe receiver is stable and reliable.When a heating cycle is stable,the temperature fluctuations both on heat-pipe wall and in PCM canister remain less than 13 K throughout a sunlight and eclipse cycle.The utility of PCM is essentially improved.The maximum melting ratio of PCM is 92%.Under gravity,PCM melts more quickly with the effect of natural convection.Natural convection accelerates the process of phase changes.Numerical results are compared with the experimental results concerned.The accuracy of numerical model under gravity is verified.The experiment for the PCM canister on the ground can be well prepared with our numerical simulation.
基金financially supported by National Natural Science Foundation of China(Grant No.51476172)
文摘Based on theoretical analysis of PCM(Phase Change Material) solidification process, the model of improved void cavity distribution tending to high temperature region is established. Numerical results are compared with NASA(National Aeronautics and Space Administration) results. Analysis results show that the outer wall temperature, the melting ratio of PCM and the temperature gradient of PCM canister, have great difference in different void cavity distribution. The form of void distribution has a great effect on the process of phase change. Based on simulation results under the model of improved void cavity distribution, phase change heat transfer process in thermal storage container is analyzed. The main goal of the improved designing for PCM canister is to take measures in reducing the concentration distribution of void cavity by adding some foam metal into phase change material.
