Theoretical study on leakage characteristics of water-injected single screw vapor compressors with a multicolumn envelope meshing pair. (25th January 2023)

• Record Type: Journal Article
• Authors: Wang, Zengli; Yuan, Qizhen; Wang, Jun; Geng, Maofei
• Is Part Of: Applied thermal engineering. Volume 219(2022)Part A
• Publication Date: 2023-01-25
• Subjects: Water-injected -- Single-screw vapor compressor -- Leakage characteristic -- Mathematical modeling -- Multicolumn envelope meshing pair; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2022.119430
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: Leakage characteristic mathematical models of SSVC with MEMP were established. Leakage models were proved to simulate the leakage characteristics of SSVC well. Leakage characteristics of the SSVC with MEMP have been analyzed. Effects of operating-structural parameters on leakage performances were analyzed. Abstract: For a water-injected single-screw vapor compressor (SSVC), leakage is an important issue that affects the compressor performance. However, the leakage mechanism of an SSVC with a multicolumn envelope meshing pair (MEMP) is unclear. In this paper, leakage characteristic mathematical models of an SSVC with MEMP are established and solved, including the orifice plate model, parallel plate model covered by a water–vapor two-phase film and Laval nozzle model considering the flash evaporation process. The calculation results are compared and verified by experimental data, and the error of the exhaust temperature and leakage coefficient is within 5%. Based on the verified mathematical model, the leakage characteristics of an SSVC with MEMP and the influence of the operating parameters and structural parameters on them are analyzed and discussed. Of all leakage channels, only the path between the front side of the screw groove and wall is inward leaking. The leakage of the plate channel is mainly water, while the Laval nozzle and orifice plate channels are mainly two-phase. The volumetric efficiency of SSVC can be increased by 6.5% and 2.65% by reducing the rotational speed and evaporation pressure by 50%, respectively. This study can provide a theoretical basis for the compressor performance analysis.