Impact of micro-grooves in scroll wrap tips on the performance of a trans-critical CO2 scroll compressor. (November 2021)

• Record Type: Journal Article
• Authors: Zheng, Siyu; Wei, Mingshan; Hu, Chenxing; Song, Panpan; Tian, Ran; Li, Yaohong; Sun, Jixian; Wu, Ding
• Is Part Of: International journal of refrigeration. Volume 131(2021)
• Page Start: 493
• Page End: 504
• Publication Date: 2021-11
• Subjects: Scroll compressor -- Carbon dioxide -- Radial leakage -- Micro grooves -- Flow control -- Numerical analysis; Compresseur à spirale -- Dioxyde de carbone -- Fuite radiale -- Micro-rainures -- Régulation du débit -- Analyse numérique; Refrigeration and refrigerating machinery -- Periodicals; 621.56
• DOI: 10.1016/j.ijrefrig.2021.06.021
• Languages: English
• ISSNs: 0140-7007

Abstract

Highlights: Micro-grooves on scroll wrap tips limit the radial leakage. Increasing groove number leads to the decrease of the radial leakage. Appropriate groove depth brings optimal flow control effect of the radial leakage. The number of groove partitions determines the availability of micro-grooves. Abstract: Radial leakage was commonly regarded as the primary factor restricting the aero-thermodynamic performance of scroll compressors. In this paper, a passive flow control approach of micro-grooves in scroll wrap tip for the radial leakage in the scroll compressor was proposed, and its flow characteristics were numerically investigated. The impact of micro-grooves geometric parameters, such as groove number, depth, and partitions, on the flow control effect of the radial leakage was discussed, which was obtained by analyzing the evolution of the flow field and its influence on the performance of the scroll compressor. Results showed that the adoption of micro-grooves in scroll wrap tip yielded a significant limitation on the radial leakage, and geometrical parameters of the micro-grooves directly affected the flow control performance. Increasing groove numbers and partitions decreased the radial leakage effectively, while the leakage decreased first and then increased with the increase of the groove depth. The energy dissipation induced by the continuous throttling effect, jet expansion, and vortex in the groove cavity was the main flow control mechanism. The quadruple-grooves with the groove width of 0.5 mm and the groove depth of 100 μm were adopted in this study eventually. The volumetric and isentropic efficiency of the scroll compressor raised up 2.1 and 1.0 percentage point compared to the original case, respectively. Through reasonable working conditions and micro-grooves geometry, the aero-thermodynamic performance of the oil-free scroll compressor could be improved effectively by the scroll wrap tip with micro-grooves.