Modeling of a Two-Stage Rotary Compressor

This paper presents the development and validation of a computer model for hermetic two-stage rotary compressors that can be used for design optimization. The model considers the effects of refrigerant leakage between the compressor chambers, heat transfer between the cylinder wall and the refrigerant gas, and heat loss by natural convection to the surroundings. The model numerically solves mass and energy balances for each of the compressor's chambers to predict the pressure and temperature variations over a crankshaft revolution. The compressor power input and refrigerant mass flow rate are calculated and used to determine the isentropic and volumetric efficiencies. The model can operate both with and without intercooling between the stages to allow for study of the effects of intercooling on compressor performance. The model results are compared to the results of external performance tests that were conducted using a prototype compressor. The intermediate temperature and pressure, discharge temperature, power consumption, and mass flow rate were recorded for 17 different operating conditions. The model predicts the compressor power consumption and mass flow rate within ±5% of the experimental results.

[1]  James E. Braun,et al.  Mathematical modeling of scroll compressors. Part I: compression process modeling , 2002 .

[2]  James E. Braun,et al.  Mathematical modeling of scroll compressors — part II: overall scroll compressor modeling , 2002 .

[3]  J. Drnovsek,et al.  Calculation and proper presentation of the measurement uncertainty in testing , 2002, IMTC/2002. Proceedings of the 19th IEEE Instrumentation and Measurement Technology Conference (IEEE Cat. No.00CH37276).

[4]  S. K. Padhy,et al.  Heat transfer analysis of a rolling-piston rotary compressor , 1994 .

[5]  Tadashi Yanagisawa,et al.  Leakage losses with a rolling piston type rotary compressor. II. Leakage losses through clearances on rolling piston faces , 1985 .

[6]  Tadashi Yanagisawa,et al.  Leakage losses with a rolling piston type rotary compressor. I. Radical clearance on the rolling piston , 1985 .

[7]  T. Yanagisawa,et al.  Volumetric efficiency and experimental errors of rotary compressors , 1980 .

[8]  Eckhard A. Groll,et al.  MODELING AND TESTING OF AN AUTOMOBILE AC SCROLL COMPRESSOR, PART I: MODEL DEVELOPMENT , 2004 .

[9]  J. Yang,et al.  Mechanical Loss Analysis Of Inverter Controlled Two Cylinders Type Rotary Compressor , 2002 .

[10]  N. Ishii,et al.  NET EFFICIENCY SIMULATIONS OF COMPACT ROTARY COMPRESSORS FOR ITS OPTIMAL PERFORMANCE , 2000 .

[11]  Kiyoshi Sano,et al.  CALCULATIONS FOR COMPRESSION EFFICIENCY CAUSED BY HEAT TRANSFER IN COMPACT ROTARY COMPRESSORS , 2000 .

[12]  Taylor Francis Online.  HVAC & R research , 1995 .

[13]  Alvaro T. Prata,et al.  Considerations About the Leakage Through the Minimal Clearance in a Rolling Piston Compressor , 1990 .

[14]  Jang-Hwan Lee,et al.  Performance analysis of rolling piston type rotary compressor , 1988 .

[15]  D. Costa,et al.  Use of a Simulation Model for Theoretical Optimization Analysis of a Rolling-Piston Type Rotary Compressor , 1986 .

[16]  K. Okada,et al.  Motion of Rolling Piston in Rotary Compressor , 1982 .

[17]  T. Yanagisawa,et al.  Motion Analysis of Rolling Piston in Rotary Compressor , 1982 .