Theoretical and experimental investigation of design parameter effects on the slip phenomenon and performance of a centrifugal compressor

• Published in: Scientia Iranica. Transaction B, Mechanical engineering Vol. 28; no. 1; pp. 291 - 304
• Main Authors: Rajabpour, S, Benisi, A Hajilouy, Manzari, M T
• Format: Journal Article
• Language: English
• Published: Tehran Sharif University of Technology 01.01.2021
• Subjects: Accuracy; Blades; Centrifugal compressors; Computational fluid dynamics; Design parameters; Diffusers; Efficiency; Exit angle; Flow velocity; Fluid flow; Mass flow rate; Pressure ratio; Slip; Tip clearance; Turbines; Viscous flow
• DOI: 10.24200/sci.2020.53042.3040

Numerous studies have investigated driving equations used to predict the slip factor in centrifugal compressors so far. Inevitably, through these studies, the flow field characteristics have been simplified and the effects of the related parameters have been neglected. The present study, experimentally and numerically, investigates the slip phenomenon in a specific centrifugal compressor with complex blade curves and splitter blades, considering the main effective parameters such as the number of blades, exit angle, etc. To this end, a three-dimensional simulation of the viscous flow field of the compressor via an appropriate turbulence method was performed. In addition, an experimental study was carried out at certain rotational speeds and mass flow rates of the slip factor. The effects of the main parameters such as rotational speed, mass flow rate, blade number, blade exit angle, diffuser design, and tip clearance on the slip phenomenon were studied. Furthermore, different performance parameters such as pressure ratio and isentropic efficiency with slip factor were investigated. As observed, the slip factor increased upon an increase in both rotational speed and flow rate. Moreover, changing the blade number from 6 to 9 at a constant rotational speed and a mass flow rate increased the slip factor up to 27%.