Investigation on an improved heat pump AC system with the view of return air utilization and anti-fogging for electric vehicles. (25th March 2017)

• Record Type: Journal Article
• Authors: Zhang, Guiying; Zou, Huiming; Qin, Fei; Xue, Qingfeng; Tian, Changqing
• Is Part Of: Applied thermal engineering. Volume 115(2017)
• Page Start: 726
• Page End: 735
• Publication Date: 2017-03-25
• Subjects: ASHP air source heat pump -- COP coefficient of performance -- COPCR COP change rate with compressor speed -- CIP compressor input power -- ECOP equivalent coefficient of performance -- EV electric vehicle -- HVAC heating, ventilation and air conditioning -- PTC positive temperature coefficient -- RAR return air ratio; Heat pump -- Return air -- Electric vehicle -- Air-conditioning; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2016.12.143
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: An improved EV AC system using return air with continuous anti-fogging was presented. Thermal model of electric vehicle on maximum return-air-using was established. Energy-saving potential of air source heat pump & auxiliary PTC was predicted. Abstract: Utilizing the return air and fresh air properly is a promising approach to meet the demand for anti-foggy and energy-saving at the same time in electric vehicle (EV). In this paper, a concept of applying a continuous anti-fogging air curtain for front windshield glass to realize the maximum-return-air utilization in winter is presented. Accordingly, heating demand model of EV is built up by taking account of the return air ratio (RAR). The research results indicate that the heating demand can be reduced by 46.4–62.1% compared to the all-fresh-air condition when the ambient temperature is −5 °C to −20 °C. And, air source heat pump (ASHP) system performance under different RARs is tested experimentally in −20 °C ambient temperature to predict the energy-saving potentials. The coefficient of performance (COP) of ASHP decreases with the increasing of RARs. Heating capacity of ASHP presents little difference at different RARs. Equivalent COP (ECOP) is used to evaluate the EV heating, ventilation and air conditioning (HVAC) system comprehensive performance. The highest ECOP is 1.57 when the RAR is 0.46, which is 12.1% higher than that of all-fresh-air condition. Accordingly, the maximum energy saving is 40.6%. Moreover, COP change rate of ASHP with compressor speed is used to get optimal compressor speed.