Journal of Mechanical Science and Technology

The Korean Society of Mechanical Engineers (대한기계학회)
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A Study on Performance Analysis of the Helically Coiled Evaporator with Circular Minichannels

  • Kim Ju-Won (Air-conditioning Division, Digital Appliance Company, LG Electronics) ;
  • Im Yong-Bin (Department of Refrigeration and Air Conditioning Engineering, Pukyong National University) ;
  • Kim Jong-Soo (School of Mechanical Engineering, Pukyong National University)
  • Published : 2006.07.01
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Abstract

In order to develop a compact evaporator, experiments that show characteristics of evaporating heat transfer and pressure drop in the helically coiled minichannel were performed in our previous research. This study was focused on the performance analysis of helically coiled heat exchangers with circular minichannels with an inner diameter=1.0 mm. The working fluid was R-22, and the properties of R-22 were estimated using the REFPROP program. Numerical simulation was performed to compare results with the experimental results of the helically coiled heat exchanger. As the heat transfer rate and pressure drop were calculated at the micro segment of the branch channels, the performance of the evaporator was evaluated. The following conclusions were obtained through the numerical simulations of the helically coiled heat exchanger. It showed good performance when the flow rate of each branch channels was suitable to heat load of air-side. The numerical simulation value agreed with experimental results within ${\pm}15%$. In this study, a numerical simulation program was developed to estimate the performance of a helically coiled evaporator. And, an optimum helically coiled minichannels evaporator was designed.

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References

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