Research On Testing System And Method Of Radiation Cooling And Heating Device

As a terminal device of an air-conditioning system,a radiant cooling and heating device is increasingly used in the field of cooling and heating.For the test of its thermal performance,China has formulated relevant standards,but the research and construction of the test system are not yet complete.In the practical application of radiant panels,an estimation method is generally adopted to determine the thermal performance related parameters.The error is large,which is not conducive to the accurate evaluation of its thermal performance and the development of new devices.In response to the current problems,this paper developed a thermal performance test system based on the requirements of China’s radiation cooling and heating performance test standards,and combined with the European standard EN14240,placed 12 simulated heat sources in the test chamber.Control,you can adjust the input power to achieve stable operating conditions faster and save energy consumption.You can also fine-tune the indoor and wall temperatures to improve test accuracy.Using the built test bed,create test conditions in the closed chamber,and make corresponding test research on the working performance of the test system(the steady state of the cooling and heating medium circulation system,the steady state of the test device environment,etc.)And the graphite radiation board is installed in the ceiling to carry out thermal performance experiments according to different test methods,which provides a strong reference for the study of the test methods of radiant cooling and heating devices.The following conclusions are obtained through experimental research:(1)The performance of the developed test system has reached and exceeded the requirements of national standards;(2)Under the national standard JG/T 403 test conditions,the standard unit cooling area of the radiator is q=72.24W,and the standard unit heating area is qh=121.18W.The difference in the amount of cooling per unit area is 1.87%,and the difference in the amount of heating per unit area is 1.38%.The experimental results have good consistency.(3)Under the condition that the refrigerant flow rate is nearly the same,the standard unit area cooling capacity of the internal and external heat source method is 74.37w/m2,,which is 1.92%different from the standard unit area cooling capacity under the national standard test method.Good consistency;in terms of running time,the running time of the two groups of experiments from the start to the standard cooling mode is about the same;but when switching from the standard cooling mode to other conditions,the running time of the two groups is different 35.7%,37.5%,the results show that under the same test conditions,the internal and external heat source method can effectively shorten the experimental time and save energy consumption.(4)Under the same test method,under different refrigerant flow rates,the standard unit area cooling capacity of the radiant panel differs by 22.97%.You can increase the cooling(hot)capacity of the radiant panel by increasing the flow rate of the cold(hot)media.