Numerical and experimental study of a combined solar Chinese kang and solar air heating system based on Qinghai demonstration building

To meet the heating demand in north China and reduce the pollution of traditional Chinese kang, a novel combined heating system consists of solar kang system and solar air heating system is proposed. The solar air system is built for the residents' daily heating demand. The solar kang system can store the solar energy collected in the daytime and provide a good sleeping environment at night. In this study, demonstration buildings are built in Huzhu, Qinghai province and one of them is chosen to test its thermal performance. Three different operation modes: only the solar air system works, only the solar kang system works and the whole combined system works are tested. A mathematic model of the room and combined system is built based on the demonstrating building. Output simulation results are compared with experiment data. The result shows the combined system can rise the indoor air temperature significantly and the simulation result can fit the experiment well. The indoor air temperature can keep about 18 degrees C when the ambient average temperature is 5 degrees C. Kang surface temperature can keep above 26 degrees C during the night at the same condition. The study proves the excellent heating performance of the combined system. (C) 2017 Elsevier B.V. All rights reserved.