R-744 two-evaporator system for US army high mobility multi-purpose wheeled vehicle.

Author(s) : PEUKER S., HRNJAK P.


The US Army has equipped their high mobility multipurpose wheeled vehicle with R-134a two-evaporator A/C systems and is exploring the possibility to implement a two-evaporator R-744 system. The components of the vehicle A/C systems (R-134a and R-744) were installed in the laboratory. Different breadboard versions were tested experimentally at identical ambient conditions. This paper presents how the R-744 two-evaporator breadboard system was optimized to exceed the performance of the R-134a two-evaporator breadboard system. The subject of different hardware setups (e.g. choice of expansion devices) for the R-744 two-evaporator system and their implications on performance and stability are addressed. For the case of two controllable expansion devices, the iterative process which was used to achieve good performance over a wide range of conditions, will be presented. The optimized R-744 system showed higher cooling capacity and higher COP compared to the R-134a system. The cooling capacity was increased up to 57% and the COP up to 18% compared to the R-134a system.

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  • Original title: R-744 two-evaporator system for US army high mobility multi-purpose wheeled vehicle.
  • Record ID : 2007-1732
  • Languages: English
  • Source: 2006 Purdue Conferences. 18th International Compressor Engineering Conference at Purdue & 11th International Refrigeration and Air-Conditioning Conference at Purdue [CD-ROM].
  • Publication date: 2006/07/17


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