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 a Dynamic Model for Double-Effect LiBr-$H_{2}O$ Absorption Chillers and Comparison with Experimental Data

이중효용 흡수식 냉온수기 동특성 모델 개발 및 실험결과 비교

  • Shin, Young-Gy (Department of Mechanical Engineering, Sejong University) ;
  • Seo, Jung-A (Department of Mechanical Engineering, Sejong University) ;
  • Cho, Hyun-Wook (Machinery Technology Group, R&D Center Research and Technology Headquarters) ;
  • Nam, Sang-Chul (Machinery Technology Group, R&D Center Research and Technology Headquarters) ;
  • Jeong, Jin-Hee (Machinery Technology Group, R&D Center Research and Technology Headquarters)
  • Published : 2008.12.10
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Abstract

A dynamic model has been developed to simulate dynamic operation of a real double-effect absorption chiller. Dynamic behavior of working fluids in main components was modeled in first-order nonlinear differential equations based on heat and mass balances. Mass transport mechanisms among the main components were modeled by valve throttling, 'U' tube overflow and solution sub-cooling. The nonlinear dynamic equations coupled with the subroutines to calculate thermodynamic properties of working fluids were solved by a numerical method. The dynamic performance of the model was compared with the test data of a commercial medium chiller. The model showed a good agreement with the test data except for the first 5,000 seconds during which different flow rates of the weak solution caused some discrepancy. It was found that the chiller dynamics is governed by the inlet temperatures of the cooling water and the chilled water when the heat input to the chiller is relatively constant.

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References

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