Abstract
Three-dimensional, compressible, unsteady Navier–Stokes equations are solved to investigate the flow field of a transonic centrifugal compressor with high compression ratio. The computational domain is consisted of an inlet bell mouth and an impeller with splitter blades, followed by a two-dimensional wedge vaned diffuser. The numerical method was validated by comparing the results with those of experiments in terms of aerodynamic compressor performance and flow field within the compressor passages. A detailed analysis of instantaneous and time-averaged flow field was conducted in the impeller and diffuser passages. The present study focuses on the pressure fluctuations and entropy production within the impeller and diffuser passages at the compressor design point. It is shown that the interaction between the impeller and diffuser blades leads to unsteadiness at the interface region and a pulsating behavior within the diffuser passages. Pressure waves with different convective velocities, generated by the impeller–diffuser interaction and pseudo-periodic unsteady separation bubbles, are captured in the time/space domain along the diffuser blade surfaces. The pressure fluctuation spectra were evaluated to analyze the noise characteristics of the centrifugal compressor as the main source of blade passing frequency noise. It is expected that the current unsteady Reynolds-Averaged Navier–Stokes (URANS) approach can be used as a tool for the prediction of unsteady flow and compressor noise characteristics with a proper turbulence model and well-resolved grids.
| Original language | English |
|---|---|
| Pages (from-to) | 244-256 |
| Number of pages | 13 |
| Journal | Aerospace Science and Technology |
| Volume | 70 |
| DOIs | |
| Publication status | Published - 2017 Nov 1 |
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Keywords
- Blade passing frequency
- Centrifugal compressor
- CFD
- URANS
- Vaned diffuser
ASJC Scopus subject areas
- Aerospace Engineering
Cite this
Numerical evaluation of transient flow characteristics in a transonic centrifugal compressor with vaned diffuser. / Zamiri, Ali; Lee, Byung Ju; Chung, Jin Taek.
In: Aerospace Science and Technology, Vol. 70, 01.11.2017, p. 244-256.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Numerical evaluation of transient flow characteristics in a transonic centrifugal compressor with vaned diffuser
AU - Zamiri, Ali
AU - Lee, Byung Ju
AU - Chung, Jin Taek
PY - 2017/11/1
Y1 - 2017/11/1
N2 - Three-dimensional, compressible, unsteady Navier–Stokes equations are solved to investigate the flow field of a transonic centrifugal compressor with high compression ratio. The computational domain is consisted of an inlet bell mouth and an impeller with splitter blades, followed by a two-dimensional wedge vaned diffuser. The numerical method was validated by comparing the results with those of experiments in terms of aerodynamic compressor performance and flow field within the compressor passages. A detailed analysis of instantaneous and time-averaged flow field was conducted in the impeller and diffuser passages. The present study focuses on the pressure fluctuations and entropy production within the impeller and diffuser passages at the compressor design point. It is shown that the interaction between the impeller and diffuser blades leads to unsteadiness at the interface region and a pulsating behavior within the diffuser passages. Pressure waves with different convective velocities, generated by the impeller–diffuser interaction and pseudo-periodic unsteady separation bubbles, are captured in the time/space domain along the diffuser blade surfaces. The pressure fluctuation spectra were evaluated to analyze the noise characteristics of the centrifugal compressor as the main source of blade passing frequency noise. It is expected that the current unsteady Reynolds-Averaged Navier–Stokes (URANS) approach can be used as a tool for the prediction of unsteady flow and compressor noise characteristics with a proper turbulence model and well-resolved grids.
AB - Three-dimensional, compressible, unsteady Navier–Stokes equations are solved to investigate the flow field of a transonic centrifugal compressor with high compression ratio. The computational domain is consisted of an inlet bell mouth and an impeller with splitter blades, followed by a two-dimensional wedge vaned diffuser. The numerical method was validated by comparing the results with those of experiments in terms of aerodynamic compressor performance and flow field within the compressor passages. A detailed analysis of instantaneous and time-averaged flow field was conducted in the impeller and diffuser passages. The present study focuses on the pressure fluctuations and entropy production within the impeller and diffuser passages at the compressor design point. It is shown that the interaction between the impeller and diffuser blades leads to unsteadiness at the interface region and a pulsating behavior within the diffuser passages. Pressure waves with different convective velocities, generated by the impeller–diffuser interaction and pseudo-periodic unsteady separation bubbles, are captured in the time/space domain along the diffuser blade surfaces. The pressure fluctuation spectra were evaluated to analyze the noise characteristics of the centrifugal compressor as the main source of blade passing frequency noise. It is expected that the current unsteady Reynolds-Averaged Navier–Stokes (URANS) approach can be used as a tool for the prediction of unsteady flow and compressor noise characteristics with a proper turbulence model and well-resolved grids.
KW - Blade passing frequency
KW - Centrifugal compressor
KW - CFD
KW - URANS
KW - Vaned diffuser
UR - http://www.scopus.com/inward/record.url?scp=85027976956&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85027976956&partnerID=8YFLogxK
U2 - 10.1016/j.ast.2017.08.003
DO - 10.1016/j.ast.2017.08.003
M3 - Article
AN - SCOPUS:85027976956
VL - 70
SP - 244
EP - 256
JO - Aerospace Science and Technology
JF - Aerospace Science and Technology
SN - 1270-9638
ER -