Study On Thermal And Wet Environment Of Composite System Of Radiation Panel At Different Positions And Fan Coil

At present, along with the development of radiation heating technology, the radiant heating system has been used widely in China. Due to numerous advantages of radiation cooling, the demands of winter heating and summer cooling are preferred to be met with the same radiant air conditioning system. However, because of condensation, the radiation cooling system has not been used widely in our country, and in-depth study is still needed.According to different locations of radiant panel, radiant air conditioning system can be divided into three types:ceiling radiation, floor radiation and wall radiation. Previous papers mainly focus on the ceiling radiation, while little research has been done on the floor and wall radiations, not to mention the combination of the three types. In this paper, a radiant panel laboratory of Hunan University is adopted and the composite system of the radiation cooling and fan coil is studied. The three radiation types and their combinations are measured, respectively. Combining theoretical basis, heat and humidity transfers of non-transparent exterior building envelope, transparent exterior building envelope and interior building envelope are analyzed. The equilibrium equation of heat and humidity in the composite system is calculated and the air handling process is analyzed, then the relationship between cooling load and heat gain and the effect of the radiant panel treated as cooling coil on the indoor humidity load are obtained.In addition, the composite system is simulated using FLUENT code. Indoor thermal and humidity environments of seven combined cases are compared, such as indoor vertical distribution of temperature and humidity, temperature and humidity distribution on the same horizontal plane and indoor air distribution.The results show that the combination of fan coil and radiant cooling variables which include ceiling and wall can generally meet human comfort, the combination of fan coil, wall radiant cooling and ceiling radiant cooling can has the best comfort, and the combination of fan coil and floor radiant cooling is the worst.This study has a broad significance on the practical application of the composite system composed of the radiation cooling and the fan coil.