Hysteresis behaviors of compressor rotating stall with cusp catastrophic model

To explain the effect of tip leakage flow on the performance of an axial-flow transonic compressor, the compressors with different rotor tip clearances were studied numerically. The results show that as the rotor tip clearance increases, the leakage flow intensity is increased, the shock wave position is moved backward, and the interaction between the tip leakage vortex and shock wave is intensified, while that between the boundary layer and shock wave is weakened. Most of all, the stall mechanisms of the compressors with varying rotor tip clearances are different. The clearance leakage flow is the main cause of the rotating stall under large rotor tip clearance. However, the stall form for the compressor with half of the designed tip clearance is caused by the joint action of the rotor tip stall caused by the leakage flow spillage at the blade leading edge and the whole blade span stall caused by the separation of the boundary layer of the rotor and the stator passage. Within the investigated varied range, when the rotor tip clearance size is half of the design, the compressor performance is improved best, and the peak efficiency and stall margin are increased by 0.2% and 3.5%, respectively.

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Investigating rotating stall

World Pumps ◽

10.1016/s0262-1762(20)30141-3 ◽

2020 ◽

Vol 2020 (4) ◽

pp. 18-20

Keyword(s):

Rotating Stall

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Roles of vanes in diffuser on stability of centrifugal compressor

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410019844433 ◽

2019 ◽

Vol 233 (14) ◽

pp. 5380-5392

Author(s):

Wangzhi Zou ◽

Xiao He ◽

Wenchao Zhang ◽

Zitian Niu ◽

Xinqian Zheng

Keyword(s):

High Pressure ◽

Centrifugal Compressor ◽

Dynamic Pressure ◽

Pressure Ratio ◽

Pressure Rise ◽

Rotating Stall ◽

Centrifugal Compressors ◽

Compression System ◽

The Stability ◽

Rotating Instability

The stability considerations of centrifugal compressors become increasingly severe with the high pressure ratios, especially in aero-engines. Diffuser is the major subcomponent of centrifugal compressor, and its performance greatly influences the stability of compressor. This paper experimentally investigates the roles of vanes in diffuser on component instability and compression system instability. High pressure ratio centrifugal compressors with and without vanes in diffuser are tested and analyzed. Rig tests are carried out to obtain the compressor performance map. Dynamic pressure measurements and relevant Fourier analysis are performed to identify complex instability phenomena in the time domain and frequency domain, including rotating instability, stall, and surge. For component instability, vanes in diffuser are capable of suppressing the emergence of rotating stall in the diffuser at full speeds, but barely affect the characteristics of rotating instability in the impeller at low and middle speeds. For compression system instability, it is shown that the use of vanes in diffuser can effectively postpone the occurrence of compression system surge at full speeds. According to the experimental results and the one-dimensional flow theory, vanes in diffuser turn the diffuser pressure rise slope more negative and thus improve the stability of compressor stage, which means lower surge mass flow rate.

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Modeling of Discrete Tip Injection in a Two-Dimensional Streamline Curvature Method

Volume 8: Turbomachinery, Parts A, B, and C ◽

10.1115/gt2012-69554 ◽

2012 ◽

Cited By ~ 1

Author(s):

Roland Matzgeller ◽

Richard Pichler

Keyword(s):

Rotating Stall ◽

Streamline Curvature ◽

Measurement Results ◽

Compressor Design ◽

Multistage Compressor ◽

Physical Effects ◽

Tip Injection ◽

Stability Enhancement ◽

Good Agreement ◽

Streamline Curvature Method

Fluid injection at the tip of highly loaded compressor rotors is known to be effective in suppressing the onset of rotating stall and eventually compressor instability. However, using such stability enhancement methods in a multistage compressor might not only stabilize certain stages but has also an impact on radial and axial matching. In order to account for tip injection during the early stages of compressor design, this paper focuses on the development of a method to model the physical effects underlying tip injection within a streamline curvature method. With the help of system identification it could be shown that a rotor subject to the discrete jets of tip injection adapts to the varying flow conditions according to a first order model. This information was used to generate a time-dependent input for the steady equations used with a streamline curvature method and eventually to model the unsteady response of the rotor to tip injection. Comparing the results obtained with the enhanced streamline curvature model to measurement results, good agreement could be shown which raised confidence that the influence of tip injection on axial and radial matching was sufficiently captured.

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Application of Bifurcation Theory to Axial Flow Compressor Instability

Journal of Turbomachinery ◽

10.1115/1.3262290 ◽

1989 ◽

Vol 111 (4) ◽

pp. 426-433 ◽

Cited By ~ 44

Author(s):

F. E. McCaughan

Keyword(s):

Parameter Space ◽

Bifurcation Theory ◽

Qualitative Difference ◽

Axial Flow ◽

Complete Information ◽

Rotating Stall ◽

Numerical Work ◽

System Parameters ◽

Parametric Effects ◽

Flow Compressor

When a compression system becomes unstable, the mode of response depends on the operating and system parameters, such as throttle setting and B parameter. Previous numerical work on the model developed by Moore and Greitzer has provided a limited picture of the parametric effects. Applying bifurcation theory to a single-harmonic version of the model has supplied much more complete information, defining the boundaries of each mode of response in the parameter space. Specifically this is shown in a plot of B versus throttle setting, which compares well with the corresponding map produced experimentally. We stress the importance of the shape of the rotating stall characteristic. The analysis shows the qualitative difference between classic surge and deep surge.

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