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Analysis of the Gravity Effect on the Distribution of Refrigerant Flow in a Multi-circuit Condenser  

Lee Jangho (포항공과대학교 기계공학과)
Kim Moo Hwan (포항공과대학교 기계공학과)
Publication Information
Korean Journal of Air-Conditioning and Refrigeration Engineering / v.16, no.12, 2004 , pp. 1167-1174 More about this Journal
Abstract
The method to consider gravity effect on the performance of a condenser is developed, and a simple condenser having 'nU' type two circuits is analyzed. Each circuit has the same length and inlet air-side operational conditions. The only difference between two circuits is the direction of refrigerant flow, which is exactly opposite each other between the upper 'n' type circuit and the lower 'U' type circuit. It is shown that the gravity makes the distribution of refrigerant flow uneven in the two circuits at lower refrigerant flow rates; heat transfer rate also becomes uneven. Moreover, much of the refrigerant exists as liquid state in the circuit having low refrigerant flow rate, which will make the cycle balance unstable in the refrigeration cycle system like a heat pump.
Keywords
Condenser; Gravity effect; Distribution of refrigerant flow; Circuit of refrigerant flow;
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