A steady-state model for the design and optimization of a centralized cooling system

Abdlmonem Beitelmal, Chandrakant D. Patel

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

A simplified steady-state model has been developed to describe thermodynamically the operation of a centralized cooling system. This model resolves the mass and energy equations simultaneously and uses inputs that are readily available to the design engineer. The model utilizes an empirical relationship for the compressor power as a function of cooling load and key temperatures. The outputs include the chiller coefficient of performance (COP) and the compressor actual power. The model simulation results are validated with a manufacturer performance data and compared with the experimental data collected at Hewlett-Packard Laboratories site for two chillers: a variable speed and a constant speed chiller. The results of the model are found to closely match the current experimental data with less than 5% average deviation for chiller load over 10% and with a maximum deviation of 18% at 95% chiller load. For the constant speed chiller, the chiller efficiency increases with increasing load and peaks at full load. For the variable speed chiller, the chiller efficiency peaks at part loading between 40 and 80% of the chiller full load depending on the condenser water temperature. This indicates that for variable speed chillers, the chiller design has been optimized for loading less than 100% depending on the ambient conditions, customer specifications and size of the chiller.

Original languageEnglish
Pages (from-to)1239-1248
Number of pages10
JournalInternational Journal of Energy Research
Volume34
Issue number14
DOIs
Publication statusPublished - 1 Dec 2010
Externally publishedYes

Fingerprint

Cooling systems
Compressors
Cooling
Specifications
Engineers
Temperature
Water

Keywords

  • Chiller efficiency
  • Chiller thermodynamics
  • Cooling tower
  • COP
  • Data center cooling
  • Heat transfer

ASJC Scopus subject areas

  • Energy Engineering and Power Technology
  • Fuel Technology
  • Nuclear Energy and Engineering
  • Renewable Energy, Sustainability and the Environment

Cite this

A steady-state model for the design and optimization of a centralized cooling system. / Beitelmal, Abdlmonem; Patel, Chandrakant D.

In: International Journal of Energy Research, Vol. 34, No. 14, 01.12.2010, p. 1239-1248.

Research output: Contribution to journalArticle

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