Heat Transfer Analysis And Indoor Thermal And Humid Environment Investigation Of Capillary Network Radiant Refrigeration

In this paper,a three-dimensional capillary network model is established based on reliable realworld experiments and CFD simulations to study the different factors(water supply temperature,water supply flow rate,room temperature,and radiant plate material)on the influence of capillary network heat transfer characteristics and radiation plate unit area cooling capacity;Establish an indoor model based on the actual test room,and explore different influencing factors(radiator temperature,fresh air temperature,relative distance of new air outlet,and relative humidity of fresh air)on the impact of the indoor thermal and humid environment,The thermal comfort index PMVPPD was used to analyze capillary network cooling on the effect of the thermal comfort of the room;Selecting the same simulation conditions to compare the temperature field,velocity field and relative humidity field of three different air supply methods(on-floor air return,under-floor return air and attached air jet),and explore the optimal solution of capillary radiation air conditioning combined with different air supply methods.Comprehensive analysis of the above content,draw the following conclusions:(1)Different radiation plate materials have different effects on radiation plate unit area cooling capacity.The highest radiation plate unit area cooling capacity is the concrete material,and radiation plate unit area cooling capacity is lower than the wood floor material.So it can be concluded that: concrete> tile> plaster material> gypsum board> wooden floor.(2)As a radiation material,concrete has a certain ability to store and store cold energy compared to plaster materials.At night,the remaining amount of cold or heat can be released to the room,so that the room temperature increases and decreases slowly after the air conditioner is turned off;In terms of room temperature control,plaster materials react rapidly as a radiation material compared to concrete materials.Under the same conditions,the use of plastering materials in the room as radiation material can reach the set temperature in advance compared to the use of concrete as radiation material.(3)The water supply temperature is a factor that has a significant impact on the cooling capacity of the radiator plate.the surface temperature of the radiant plate decreases as the temperature of the water supply decreases,and radiation plate unit area cooling capacity gradually increases.The supply water flow rate is a factor that has a small effect on the cooling capacity of the radiant plate.Radiation plate unit area cooling capacity varies slightly with the change in the flow rate of the supply water.(4)Radiation plate temperature is the main factor on the influence of indoor heat and humidity environment.The fresh air temperature has less impact on the indoor heat and humidity environment.The relative distance of the fresh air outlet has no effect on the indoor heat and humidity environment.The relative humidity of fresh air has no effect on the indoor average temperature and the convective heat exchange between the human body and the surrounding environment,however,the relative humidity of fresh air has a certain influence on indoor comfort.(5)The floor upper return air and the floor lower return air exhibit a similar distribution pattern in the indoor temperature field and relative humidity field.The floor upper return air is superior to the floor lower return air in the uniformity of airflow organization;and the floor upper return air is superior to the attached jet in terms of indoor relative humidity uniformity,however,in terms of the distribution of relative humidity near the radiation board,the uniformity of the attached jet is better than the return air on the floor.