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

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Dynamic Analysis of Single-Effect/Double-Lift Libr-Water Absorption System using Low-Temperature Hot Water

저온수를 이용하는 일중효용/이단승온 리튬브로마이드-물 흡수식 시스템의 동적 해석

  • Kim, Byong-Joo (Department of Mechanical and System Design Eng., Hongik University)
  • 김병주 (홍익대학교 기계.시스템디자인공학과)
  • Published : 2009.12.10
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Abstract

Dynamic behavior of Libr-water absorption system using low-temperature hot water was investigated numerically. Thermal-hydraulic model of single-effect/double-lift 100 RT chiller was developed by applying transient conservation equations of total mass, Libr mass, energy and momentum to each component. Transient variations of system properties and transport variables were analysed during start-up operation. Numerical analysis were performed to quantify the effects of bulk concentration and part-load operation on the system performance in terms of cooling capacity, coefficient of performance, and time constant of system. For an absorption chiller considered in the present study, optimum bulk concentration was found to exist, which resulted in the minimum time constant with stable cooling capacity. COP and time constant increased as the load decreased down to 40%, below which the time constant increased abruptly and COP decreased as the load decreased further.

Keywords

References

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