Application of Smart Phone in On-Site Test of Heat Transfer Coefficient of Building Envelope

With the increasing demand for on-site test of heat transfer coefficient of building envelope, a new test method is proposed aiming at the problems of common detection methods. According to the one-dimensional steady-state heat transfer theory of the envelope structure, the formula for calculating the heat transfer coefficient of the building envelope is derived based on the air temperature on both sides of the enclosure, the inner surface temperature and the inner surface heat transfer resistance. After turning the formula into a calculation program and loading the program into a smart phone, the heat transfer coefficient at the corresponding position can be obtained as long as the corresponding temperature and surface heat transfer resistance are input into the program. Comparing with the existing on-site detection methods of heat transfer coefficient and analyzing the detection results, it can be seen that the heat transfer coefficient obtained by this detection method is reliable, and that the method meets the needs of engineering detection. It is an economical, convenient, fast and reliable detection method to test the heat transfer coefficient of building envelope using smart phone and thermo detector.