Experiment And Simulation Of The Performance Of The Radiant Cooling System With Multiple Radiant Surfaces And Different Air Supply Modes

In recent years,the rapid development of China’s economy has gradually increased the requirements for the quality of life and the comfort of indoor living environments.The capillary network radiation cooling system has the advantages of no air blowing feeling,no air flu,high indoor comfort,and low energy consumption.This demand is well met.At present,the research on the performance of capillary radiant cooling systems is mainly focused on system performance experiments and simulations,but less research on system performance optimization.Based on this,this paper focuses on the following work.First,a radiant cooling laboratory in Nanjing was taken as the research object,and the performance of the radiant air-conditioning system was experimentally studied by changing the air supply method and the laying method of the capillary network,and the average indoor temperature,vertical temperature,horizontal temperature,and wall temperature,PMV-PPD and other parameters were analyzed.The experimental results show that the response time from fast to slow when the cooling status reaches stability under three different laying methods is: top surface laying,wall surface laying,The floor is laid,and under the combined air conditioning system of capillary top radiation and kick air supply,the indoor temperature field is most evenly distributed,the horizontal and vertical temperature differences are the smallest,and the indoor comfort is the best.Secondly,using AIRPAK software,on the basis of experiments,establish radiant cooling models under different capillary laying methods(top surface,wall surface,and floor),respectively,indoor temperature field and velocity field under ground air supply and kick air supply,Relative humidity,PMV-PPD were analyzed,and the system optimized operation scheme was obtained by comparing and analyzing the numerical simulation results with experimental results.Finally,based on experiments and numerical simulations,a multi-point air supply operation mode based on radiant ceiling cooling was proposed,and the optimized scheme was further numerically simulated to analyze the indoor temperature field,velocity field,relative humidity,PMV-PPD and other parameters change,exploring the distribution of indoor humid and hot environment with different number of air outlets.Based on this optimal air supply method,a top + wall radiation model,a top + ground radiation model,and a ground + wall radiation model is established.The system performance under the multi-surface radiation cooling model is analyzed,and the results show that the indoor When the load is large,the top surface + wall surface radiation model is more in line with the requirements of indoor human comfort.