An experimental investigation of natural convection heat transfer over outer surface of vertical helical coil condenser

Rajesh Kumar, Prabhansu -, Prakash Chandra

Abstract


Free convection heat transfer over the outer surface of helical coil condenser (HCC) and existing wire-on-tube condenser (WOTC) in air was experimentally studied under steady state condition. Two types of condenser are tested: helical coil condenser of different coil diameter to tube diameter ratio and an existing wire-on-tube condenser. The experiments were conducted for turbulent flow outside, the helical coil surface as well as, conventional wire-on-tube condenser surface and comparative analysis was done. The experimental results show that decrease in diameter ratio as well as pitch leads to increase in outside heat transfer coefficient. 12.42% higher outside heat transfer coefficient was obtained for helical coil condenser in comparison with the conventional wire-on-tube condenser. It was also observed that the COP of the domestic refrigerator with designed HCC is 12.77 % higher than existing WOTC.


Keywords


Domestic refrigerator; existing wire-on-tube condenser; free convection; helical coil condenser; outside heat transfer coefficient.

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References


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