Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Performance Variation with Length of Internal Heat Exchanger in CO2 Cooling Cycle Using an Ejector

이젝터를 적용한 이산화탄소 냉동사이클의 내부열교환기 길이에 따른 성능 변화

  • Kang, Byun (Graduate School of Mechanical Engineering, Chosun University) ;
  • Cho, Hong-Hyun (Department of Mechanical Engineering, Chosun University)
  • 강변 (조선대학교 대학원) ;
  • 조홍현 (조선대학교 기계공학과)
  • Received : 2011.10.06
  • Published : 2012.02.10
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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.

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References

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