A Simplified Model of Semi-Open Impeller Stage and Analysis of its Effects on the Transient Flow

Abstract:

The centrifugal compressor is one type of vital energy conversion equipment and its unsteady characteristics are extremely complex in actual operation. A semi-open impeller stage with inlet guide vanes, an impeller and a diffuser in a centrifugal compressor was concerned. For simulation of unsteady flow, the full-passage model of the integrate stage requires much more simulating time and memory space, higher computer configuration. Therefore, a single-passage simplified model was established for unsteady analysis. The internal flow characteristics and aerodynamic load on the blade obtained by the simplified model were also compared with that by the full-passage model. The result shows that the precision of the simplified model can meet the engineering requirement. Compared with the full-passage model, the simplified model can give a relatively true reflection of the local flow characteristics and the aerodynamic load on blade surfaces, but it ignores the unevenness resulted from unsteadiness along circumferential direction. Only high-frequency information is retained in aerodynamic load analysis while low-frequency one is diluted. However, as far as the local flow pattern or high-frequency information resulted from unsteady effects is concerned, the simplified model provides the advantages of higher computational efficiency and lower hardware requirements.

• Periodical: Applied Mechanics and Materials (Volume 721)
• Pages: 82-86
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.721.82
• Online since: December 2014
• Authors: Mu Ting Hao, Rong Xie*, Liang Guan, Zi Fu Lu
• Keywords: Semi-Open Impeller, Simplified Model, Unsteady Analysis

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