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
热管堆属于小型模块化反应堆,具有结构简单、建造方便、易于部署等特点,其运行于负荷跟踪模式。KRUSTY(Kilowatt Reactor Using Stirling TechnologY)作为热管堆Kilopower的原型机,已经经过了相关测试并取得了令人满意的结果。为了进一...热管堆属于小型模块化反应堆,具有结构简单、建造方便、易于部署等特点,其运行于负荷跟踪模式。KRUSTY(Kilowatt Reactor Using Stirling TechnologY)作为热管堆Kilopower的原型机,已经经过了相关测试并取得了令人满意的结果。为了进一步优化KRUSTY的结构,深入理解保温层对反应堆的影响,提升反应堆输出能量的效率,特此对其展开研究。通过多物理场软件Simscape对KRUSTY进行建模,并根据模型进行6种不同程度的修改方案,计算了0.6$反应性启动、±4×10^(-4)反应性引入以及±50%负荷改变工况下各个方案的反应堆行为。其中,多层保温材料(Multilayer Insulation,MLI)加倍方案的能量输出效率最高,达到了79.71%。结果表明:在堆芯、真空罐、反射层等结构间增加空隙数量,并且真空罐内部含有较厚保温层的情况下,反应堆导出能量的效率更高。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.
