相变蓄热供热装置热性能试验研究与系统经济性分析

为分析相变蓄热装置在充热和放热过程中的热性能，设计并搭建一套相变蓄热供热装置中试实验系统，研究主要运行参数对相变蓄热装置热性能的影响；在此基础上，结合项目案例，对相变蓄热供热系统经济性进行分析。结果表明：相变材料(Phase Change Material, PCM)凝固过程中的传热主要受相变介质内部导热控制；而在其熔化过程中自然对流对传热起重要控制作用；蓄热装置充热速率快于放热速率。提高传热流体流量有助于增强PCM中的热传递，缩短充/放热时间，但蓄热装置内PCM温度分布均匀性有所降低；为降低系统能耗，提高储放热效率，优先选用小流量进行充/放热。该相变蓄热供热项目的动态投资回收期为3.55年，具有良好的经济性。研究结果可对相变蓄热供热系统的设计及应用推广提供参考依据。

Experimental Study on Thermal Performance and System Economic Analysis of Phase Change Heat Storage Heating Unit

In order to analyze the thermal performance of the phase change heat storage device during the charging and discharging process,a phase change heat storage heating system was designed and constructed,and the effect of major operating parameters on the thermal performance of the phase change heat storage device was studied.On this basis,combined with the project cases,the economy of phase change heat storage heating system was analyzed.The results show that the heat transfer of phase change material (PCM) during discharging process is mainly controlled by the internal thermal conduction mechanism,while the natural convection effect plays an important role in controlling heat transfer during the charging process.The charging rate is faster than the discharging rate.Increasing the flow rate of the heat transfer fluid (HTF) during the charging and discharging process can obviously enhance the heat transfer rate in PCM and shorten the charging/discharging time,but the uniformity of temperature distribution in PCM decreases.In order to reduce the energy consumption of the system and improve the charging and discharging efficiency of the heat storage device,low flow HTF is preferentially selected for charging and discharging of the device.Economic analysis shows that the dynamic investment payback period of phase change heat storage heating system is 3.55 years,which has good economy.The research results can provide reference for the design and application of phase change heat storage heating system.