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

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Development of an Electric Circuit Transient Analogy Model in a Vertical Closed Loop Ground Heat Exchanger

수직밀폐형 지중열교환기의 회로 과도해석 상사모델 개발

  • Kim, Won-Uk (Department of Mechanical Engineering, Graduate School of Korea University) ;
  • Park, Hong-Hee (Department of Mechanical Engineering, Graduate School of Korea University) ;
  • Kim, Yong-Chan (Department of Mechanical Engineering, Korea University)
  • Received : 2011.11.16
  • Published : 2012.04.10
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Abstract

Several numerical or analytical models have been proposed to analyze the thermal response of vertical ground heat exchangers (GHEX). However, most models are valid only after several hours of operation since they neglect the heat capacity of the borehole. Recently, the short time response of the GHEX became important in system simulation to improve efficiency. In this paper, a simple new method to evaluate the short time response of the GHEX by using an analogy model of electric circuit transient analysis was presented. The new transient heat exchanger model adopting the concept of thermal capacitance of the borehole as well as the steady-state thermal resistance showed the transient thermal resistance of the borehole. The model was validated by in-situ thermal response test and then compared with the DST model of the TRNSYS program.

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References

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