Research On The Solar Low-temperature Hot Water PCM Wallboard Radiant Heating System

low-temperature hot water radiant heating technology has developed rapidly in recent years,while low-temperature hot water radiant heating system has been widely used all over the world.This paper introduces the radiant heating technology and achievements of the phase-transition area in both domestic and foreign research papers,then explores radiant heating characteristics of the the PCM wallboard heated by low-temperature hot water,subsequently establishes the accurate mathematical model of the low-temperature hot water radiant PCM wallboard.Based on the established model and given boundry conditions,the numberical calculation software-Fluent is to be used to simulate radiant heating characteristics of the PCM wallboard.The impact of fluid volecity,time of thermal storage and rejection,water temperature,designed room temperature,phase transition temperature and phase-transition layer thickness on PCM wallboard's inner surface temperature,wall surface temperature and heat flux changes in the process of phase-transition heat transfer has been analyzed.A low-temperature hot water radiant PCM wallboard heating system bench has been established.The simulation data and the experimental data are to be compared to verify model reliability.Under the premise of the research of the PCM wallboard heating characteristics,this paper puts forward solar PCM wallboard radiant heating system.Fluent is used to study the temperature distribution of indoor environment,in which,with dynamic heat load,the PCM wall board is heated by solar power as the only heat source.in cold winter.Results of this paper offers a certain reference value for the design of low-temperature hot water radiant heating system,and,provides a theoretical basis for the combination of solar energy and the radiant heating system.