Abstract
An adjustable ejector expansion device for a CO2 heat pump water heater (HPWP) is proposed to improve the system performance. It has been designed to investigate experimentally the effects of the motive nozzle throat area of the ejector, entrained flow pressure, back pressure and primary flow pressure on the entrainment ratio. Experiments based on different motive nozzle throat areas were conducted and the results of the prototype ejector using CO2 as working fluid are presented. The results show that an adjustable ejector can achieve high performance and work well in a wide range of working conditions.
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Project supported by the National Key Technologies R&D Program of China (No. 2006BAJ01A10), and the Science and Technology Plan of Zhejiang Province (No. 2007C01002), China
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Chen, Gm., Liang, Lx., Tang, Lm. et al. Experimental investigation of an adjustable ejector for CO2 heat pump water heaters. J. Zhejiang Univ. Sci. A 10, 1678–1682 (2009). https://doi.org/10.1631/jzus.A0920116
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DOI: https://doi.org/10.1631/jzus.A0920116