Thermodynamic analysis on the performance of a variable speed scroll compressor with refrigerant injection

• Published in: International journal of refrigeration 2002, Vol.25 (8), p.1072-1082
• Main Authors: Park, Youn Cheol, Kim, Yongchan, Cho, Honghyun
• Format: Article
• Language: English
• Subjects: Applied sciences; Calcul; Calculation; Compresseur frigorifique; Compresseur spirale; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Injection intermédiaire; Refrigerant injection; Refrigerating compressor; Refrigerating engineering; Refrigerating engineering. Cryogenics. Food conservation; Scroll compressor; Techniques. Materials; Variable speed; Vitesse variable
• ISSN: 0140-7007; 1879-2081
• DOI: 10.1016/S0140-7007(02)00007-5

A thermodynamic model for a variable speed scroll compressor with refrigerant injection was developed using continuity, energy conservation and real gas equation. The model included energy balance in the low-pressure shell compressor, suction gas heating, motor efficiency, and volumetric efficiency considering gas leakages as a function of compressor frequency. The developed model was verified by comparing the predicted results for the no injection condition with the experimental data. The deviations of the predicted from the measured values were within 10% for approximately 90% of the experimental data. Based on the model, mass flow rate, suction gas heating, cooling capacity and power consumption of the compressor were estimated and analyzed as a function of frequency. The effects of refrigerant injection on the performance of the compressor were also discussed as a function of frequency, injection conditions, and injection geometry. A thermodynamic model for a variable speed scroll compressor with refrigerant injection was developed using continuity, energy conservation and real gas equation. The model included energy balance in the low-pressure shell compressor, suction gas heating, motor efficiency, and volumetric efficiency considering gas leakages as a function of compressor frequency. The developed model was verified by comparing the predicted results for the no injection condition with the experimental data. The deviations of the predicted from the measured values were within 10% for approximately 90% of the experimental data. Based on the model, mass flow rate, suction gas heating, cooling capacity and power consumption of the compressor were estimated and analyzed as a function of frequency. The effects of refrigerant injection on the performance of the compressor were also discussed as a function of frequency, injection conditions, and injection geometry.