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http://dx.doi.org/10.6110/KJACR.2013.25.3.137

An Experimental Study on the Performance Characteristics of Hot-gas and Liquid Bypass Heat Pump Systems for Capacity Modulation  

Ahn, Jae Hwan (Department of Mechanical Engineering, Graduate School of Korea University)
Joo, Youngju (Digital Appliance Division, Samsung Electronics Inc.)
Yoon, Won Jae (Department of Mechanical Engineering, Graduate School of Korea University)
Kang, Hoon (Department of Mechanical Engineering, Korea University)
Kim, Yongchan (Department of Mechanical Engineering, Korea University)
Publication Information
Korean Journal of Air-Conditioning and Refrigeration Engineering / v.25, no.3, 2013 , pp. 137-142 More about this Journal
Abstract
A small air-conditioner or chiller for a constant temperature bath normally uses a constant speed compressor. The constant speed compressor is relatively inexpensive, but it uses on/off control for capacity modulation. The on/off control has several disadvantages, specifically energy loss and large temperature fluctuation. Continuous operation with a bypass system can be an alternative to on/off control, for capacity modulation. In this study, a heat pump system having a hot-gas bypass and a liquid bypass was adopted. The performance of the bypass-type heat pump was measured, by varying the bypass valve opening. The differences of the COP between the hot-gas bypass and the liquid bypass, in the cooling and heating operations, were within 2% and 1%, respectively. The liquid bypass showed a wider range of capacity control in the cooling operation but the hot-gas bypass showed a wider range of capacity control in the heating operation.
Keywords
Hot-gas bypass; Liquid bypass; Heat pump; Capacity modulation;
Citations & Related Records
Times Cited By KSCI : 4  (Citation Analysis)
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