Simulation of floating condensing temperature control for air-cooled chillers.

Author(s) : YU F. W., CHAN K. T.

Summary

The study aims to develop a thermodynamic model for an air-cooled screw chiller to investigate how the condensing temperature should be controlled to improve its COP. The model considers real process phenomena, including the capacity control of compressors and the overall heat transfer coefficients of an evaporator and a condenser at part load. A new configuration of variable speed condenser fans was proposed. An algorithm was introduced to make use of a set point of condensing temperature to determine the number and speed of condenser fans staged at any given operating conditions. The model was validated using the operating data and specifications of an existing chiller. The simulation results showed that the chiller COP drops considerably, especially at part load operation with moderate temperatures when using the conventional head pressure control with a fixed and high set point of 45°C for the condensing temperature. In order to maximize the chiller COP, the set point should be adjusted in response to changes of the chiller load and outdoor temperature.

Details

  • Original title: Simulation of floating condensing temperature control for air-cooled chillers.
  • Record ID : 2007-0796
  • Languages: English
  • Source: ACRA-2006. Proceedings of the 3rd Asian conference on refrigeration and air conditioning.
  • Publication date: 2006/05/21

Links


See other articles from the proceedings (161)
See the conference proceedings