Performance Characteristics of a Mobile Heat Pump System at Low Ambient Temperature

The demand for mobile heat pump systems increases with the growing popularity of electric vehicles. One big challenge of such systems using low pressure refrigerant is the substantial drop of heating capacity at low ambient temperature conditions, when heat is most needed. The low suction density associated with low operating pressure in the evaporator is the major reason for the capacity drop. In extremely low ambient temperature, compressor speed may need to be regulated in order to prevent suction pressure going below atmospheric pressure, hence further reducing heat pumping capability. Other factors like pressure drop induced temperature glide and refrigerant maldistribution in the outdoor evaporator also weakens the system ability to absorb heat from ambient air. This paper presents detailed and in-depth analysis of the performance and limiting factors on low ambient temperature operation of a mobile heat pump system using refrigerant R1234yf. Experimental data are taken for ambient temperatures ranging from -20 to 20 °C. Analysis of losses are presented with the aid of a simulation model.

• Record URL:
  • https://doi.org/10.4271/2018-01-0076
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/01487191
• Supplemental Notes:
  • Abstract reprinted with permission of SAE International.
• Authors:
  • Feng, Lili
  • Hrnjak, Predrag
• Conference:
  • WCX World Congress Experience
  • Location: Detroit Michigan, United States
  • Date: 2018-4-10 to 2018-4-12
• Publication Date: 2018-4-3

Language

• English

Media Info

• Media Type: Web
• Features: References;
• Serial:
  • SAE Technical Paper
  • Publisher: Society of Automotive Engineers (SAE)
  • ISSN: 0148-7191
  • EISSN: 2688-3627
  • Serial URL: http://papers.sae.org/

Subject/Index Terms

• TRT Terms: Atmospheric temperature; Electric vehicles; Heating, cooling and ventilation equipment; Performance; Pumps; Refrigerants
• Uncontrolled Terms: Heat pumps
• Subject Areas: Energy; Highways; Vehicles and Equipment;

Filing Info

• Accession Number: 01693135
• Record Type: Publication
• Source Agency: SAE International
• Report/Paper Numbers: 2018-01-0076
• Files: TRIS, SAE
• Created Date: Feb 19 2019 11:53AM