Performance analysis of a dehumidifier using HFC134a

Abstract

The paper analyses the operating characteristics for a medium-temperature dehumidifier employing a passive evaporator economizer and staged liquid subcooling. The refrigerant was HFC134a and the compressor was a compliant scroll with a swept volume of 14.8 m 3 h −1. The measurements were made in a psychrometric calorimeter and the data consistency is assessed by applying energy and moisture balance criteria. Local energy balance is used to determine the incidental heat gain of the evaporator. It is suggested the compressor energy balance was affected by refrigerant dissolved in the lubricant at the highest evaporating pressures tested (900 kPa). The maximum measured specific moisture extraction rate of the dehumidifier was 5.11 kg kWh −1 at 50°C dry-bulb temperature and 90% relative humidity. The results illustrate the potential for scroll compressors, and the use of HFC134a, in this application.