Development of Large Capacity 3D Scroll Compressor for First Stage of Two-stage Compression System

摘要

Two-stage compression systems are used in heat pump products such as heat pump water heater and hot wind dryer to expand applicable range and improve their performance. For first stage of two-stage compression system in large capacity heat pump water heater, the authors developed a large capacity scroll compressor. The developed compressor has larger displacement volume than our conventional compressors with same external dimensions of compressor. To increase displacement volume, the authors adopted a three dimensional scroll and optimized scroll involute parameters as larger orbiting radius and less number of involute turns, compared to the conventional scroll. These lead to increase in displacement volume about 1.9 times to the conventional two dimensional scroll. Test results of the developed compressor show 1% to 8% improvement in compressor efficiency compared to the conventional compressor, because lower rotating speed to obtain same heating capacity results in reduction of mechanical losses. The developed compressor is installed in a newly developed heat pump water heater and contributes its performance.