Analysis And Research The Heat Transfer Characteristic Of Radiant Panel Heating And Cooling

It is an energy-saving method to use radiant panel to reduce the energy consumption of air conditioning system.Besides,if we use a same piece of radiant panel to supply heat in winter and provide cooling capacity in summer,we could not only save energy but also reduce the initial investment.This paper starts from the analysis of heat transfer of radiant panel itself,through experimental method and numerical simulation.First,set up an experiment platform to measure the influence of water supply temperature,indoor temperature,water supply flow rate and the surface wind speed of radiation panel on the surface temperature distribution of radiation panel and the time which the surface temperature of radiant panel system required to reach stable.In summer,when the water supply temperature increases by 1?,the surface temperature of radiation panel increases by 0.7?~0.9?.The lower the water supply temperature is,the unevener the surface temperature distribution of radiation panel will be.In winter,when the radiation panel temperature increases by 5?,the surface temperature of radiation panel increases by 2.6?~4.2?.The higher the water supply temperature is,the unevener the surface temperature distribution of radiation panel will be.The surface temperature of radiation panel is affected by pipeline greatly.On the basic of experiment,set up the physical heat transfer model of radiant panel,then,use CFD software to launch numerical calculation on three-dimensional fluid-structure coupling heat transfer model and analyse the heat exchange problem among indoor air,indoor wall and water temperature of radiant panel.We obtained the influence of water supply temperature,return water temperature difference,water velocity,coil spacing,floor materials,radiant panel thickness and hole diameter on the heat exchange quantity and the surface temperature distribution of radiant panel.Also,we achieved the calculation formula among the average return water temperature,indoor temperature difference and the heat exchange quantity.Based on all these factors above,we drew a conclusion that the radiant panel surface temperature distribution is affected by water supply temperature and the coil spacing greatly,the water velocity has a little influence on the surface temperature of radiant panel.Under the condition of without considering heat storage,the smaller radiant panel thickness is,the higher heat exchange quantity will be.At last,take a single room of an office building in Beijing as the research object,we applied the surface temperature distribution of radiant panel above to this room by CFD commercial software Airpak3.0,obtained the influence of the radiant panel position on indoor temperature,PMV-PPD and the air non-uniform coefficient.We achieved the best position of radiant panel used both in summer and winter.Radiant panel on the wall is the best postion when the radiant panel is used both in summer and winter.