Centrifugal chillers: Thermodynamic modelling and a diagnostic case study

doi:10.1016/0140-7007(95)96863-2

International Journal of Refrigeration

Volume 18, Issue 4, May 1995, Pages 253-257

https://doi.org/10.1016/0140-7007(95)96863-2 Get rights and content

Abstract

The diagnostic capability of a simple thermodynamic model for chiller performance is illustrated by a case study for a commercial, installed centrifugal chiller. Performance data were measured both prior to, and subsequent to, chiller maintenance that improved chiller efficiency. Using these experimental measurements, we show that the simple thermodynamic model, originally developed for reciprocating and absorption chillers, (1) succeeds in predicting the fundamental relation between coefficient of performance and cooling rate for the centrifugal chiller, and (2) permits a clear diagnostic analysis of heat exchanger fouling on chiller performance.

Résumé

On démontre, par le biais d'une étude de cas d'un refroidisseur centrifuge commercial, déjà installé, les possibilités d'un modèle thermodynamique simple pour l'évaluation des performances des refroidisseurs. On a mesuré les données de performance avant et après une opération d'entretien qui a amélioré le rendement du refroidisseur. Avec l'appui de ces mesures expérimentales, nous montrons que le modèle thermodynamique simple, mis au point, à l'origine, pour les refroidisseurs à piston et à absorption, permet, d'une part, de prévoir la relation fondamentale entre le coefficient de performance et la puissance frigorifique pour le refroidisseur centrifuge et, d'autre part, d'effectuer un diagnostic clair de l'effet de l'encrassement des échangeurs de chaleur sur la performance du refroidisseur.

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^∗: On sabbatical leave from: Center for Energy and Environmental Physics, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 84993, Israel, and the Pearlstone Center for Aeronautical Engineering Studies, Department of Mechanical Engineering, Ben-Gurion University of the Negev, Beersheva, Israel.

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Centrifugal chillers: Thermodynamic modelling and a diagnostic case studyRefroidisseurs d'eau à group centrifuge: Simulation thermodynamique et étude d'un cas de figure

Abstract

Résumé

Heat Recovery Systems and CHP

Energy Int J

Thermodynamic modeling of reciprocating chillers

J Appl Phys

Modern Refrigerating Machines

Optimal chiller loading

ASHRAE J