Experimental investigation of a heat pump assisted drum drying system using propane (R290) as working fluid

摘要

This study experimentally investigates the suitability of R290 in replacement of R134a asrefrigerant in a mass-produced heat pump assisted drum dryer. A heat pump assisted drum dryerdesigned for R134a is instrumented and rebuilt by replacement of the compressor and in turn thecapillary tube. The effect of R290 charge optimization and capillary tube accommodation isinvestigated. Input power, refrigerant pressure and temperature as well as temperature andhumidity of the airstream is logged. By replacing only the compressor, the R290 system obtainedthe same level of efficiency as the original R134a system. Subsequent to replacement of thecapillary tube 6% increase in COP was observed, maintaining the same level of SMER as withR134a.