Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10126879 | Energy and Buildings | 2018 | 14 Pages |
Abstract
A defrosting initiation strategy based on tube-encircled photoelectric sensors (TEPS) was previously proven effective for enhancing the frosting-defrosting performances of air source heat pumps (ASHPs) in cold and dry regions. To verify its applicability to, and evaluate the energy-saving potential when using the TEPS-based strategy in mild and humid regions, field tests were conducted in Guiyang City, China, where the outdoor averaged air temperature and relative humidity were 4.5 °C and 80% in winter, respectively. Two ASHPs of the same-make, one with the TEPS-based strategy and the other with the commonly used temperature-time (TT) strategy, were tested. Totally, seven test cases were organised. Cases 1-5 were for short-term tests to verify the technical feasibility of TEPS-based strategy by comparing the defrosting accuracy of the two strategies. Cases 6-7 were for long-term tests to validate the reliability and effectiveness of the TEPS-based strategy by comparing two ASHPs' operating performances. The test results demonstrated that the use of TEPS-based strategy in mild and humid regions can initiate defrosting more accurately, reliably and efficiently, and thus improve the COP and heating capacity by 11.3% and 12.1%, respectively, compared to the use of the TT strategy. Therefore, it was proven that the TEPS-based strategy was more effective for the ASHPs used in mild and humid regions, for a more accurate defrosting initiation and higher energy efficiency.
Related Topics
Physical Sciences and Engineering
Energy
Renewable Energy, Sustainability and the Environment
Authors
Bai Xiaoxia, Wang Wei, Sun Yuying, Liu Jingdong, Ge Yijing, Deng Shiming,