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http://dx.doi.org/10.6110/KJACR.2012.24.2.147

Performance Variation with Length of Internal Heat Exchanger in CO2 Cooling Cycle Using an Ejector  

Kang, Byun (Graduate School of Mechanical Engineering, Chosun University)
Cho, Hong-Hyun (Department of Mechanical Engineering, Chosun University)
Publication Information
Korean Journal of Air-Conditioning and Refrigeration Engineering / v.24, no.2, 2012 , pp. 147-154 More about this Journal
Abstract
Recently, many researchers have studied the performance of the transcritical $CO_2$ refrigeration cycle in order to improve the system efficiency. In this study, the length of IHX in the $CO_2$ ejector cycle was varied so as to evaluate the performance improvement. As a result, compressor work and cooling capacity was increased by 3% and 5% as the length of internal heat exchanger was changed from 3 m to 15 m. The best COP was appeared at internal heat exchanger length of 12 m, and it was 3.01. Besides, the length of internal heat exchanger has a big effect to pressure lift ratio and entrainment ratio in the ejector $CO_2$ cycle and it may be changed with operating conditions and system specifications.
Keywords
Carbon dioxide; Transcritical system; Ejector; Internal heat exchanger;
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