A Lumped Thermal Parameter Model for Scroll Compressors Including the Solution of the Temperature Distribution along the Scroll Wraps

Marco C. Diniz
Evandro L. L. Pereira
Cesar J. Deschamps

Abstract

A lumped parameter thermal model has been developed to predict the temperature distribution of scroll compressors with especial attention to gas superheating in the suction process. Thermal resistances between the components were based on global heat transfer coefficients, whereas conduction heat transfer through the scroll wraps was solved via a one dimensional finite volume method. The thermal model was coupled to a thermodynamic model of the compression cycle and then applied to simulate the compressor performance at different conditions of speed and pressure ratio. The model was able to correctly predict the compressor temperature distribution for operating conditions within the range of those adopted for its calibration. The results showed a strong coupling between the compressor thermal profile and the temperatures of the motor and lubricating oil. The model demonstrated that heat conduction through the scroll wraps reduces slightly the discharge temperature.