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rotating stall and stall-Controlled Performance of a Single Stage Subsonic Axial Compressor

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Journal of Thermal Science 2006年第1期15卷 1-13页

作者： Eisuke OUTA Department of Mechanical Engineering Waseda University Tokyo Japan

Activities by various authors on aerodynamics and control dynamics of rotating stall in axial compressor are first traced. Then, a process of stall cell evolution in a subsonic stage is discussed based on a 2-D CFD. A few numbers of vortices grow ahead of the rotor accumulating vorticity ejected from lightly stalled blades, and eventually organize a cell of circumferentially aligned huge vortices, which merge and recess repeatedly during the rotation. Such stall disturbance is intensified on trailing side of a circumferential inlet distortion and decays on the leading side. Considering these features, a new algorithm for stall warning is developed based on a correlation between pressure waveforms at each passing of a fixed blade. A remarkable change in the correlation level at near-stall provides a warning signal prior to the stall onset with sufficiently large time margin. This scheme is applied to achieve rotating stall prevention by actuating flaps installed on the hub. The last issue is on characteristics of forward swept blade which has much increased throttle margin with decreased tip loss. A 3-D computation shows that a secondary vortex generated in suction surface mid span interacts to reduce the tip leakage vortex that initiates the stall.

关键词： rotating stall stall warning sensing stall control forward swept blade two- and three-dimensional unsteady CFD stall cell structure tip leakage flow.

Coexisting Phenomena of Surge and rotating stall in an Axial Flow Compressor

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Journal of Thermal Science 2013年第6期22卷 547-554页

作者： Takuya ABE Hiroaki MITSUI Yutaka OHTA Graduate Student Graduate School of Science and EngineeringWaseda University Department of Applied Mechanics and Aerospace Engineering Waseda University

The unsteady inner flow structure of a single-stage axial flow compressor under the coexisting conditions of surge and rotating stall was experimentally investigated via detailed measurements of the unsteady characteristics and the internal flow velocity fluctuations. The main relevant feature of the tested compressor is a shock tube with a capacity tank connected in series to the compressor outlet through slits and a concentric duplex pipe: surge and rotating stall can both be generated by connecting the shock tube. Research attention is focused on the unsteady behavior of a rotating stall during the surge cycle. The size of the rotating stall cell during the recovery process of an irregular surge cycle was experimentally determined by the circumferential flow velocity fluctuations ahead of the rotor blade. The results suggested that the size of the rotating stall cell at the switching point of the performance curve between large and small cycles is considered to be the key parameter in determining the following surge cycle. In addition, the surge cycle is largely influenced by the unsteady behavior of the rotating stall cell.

关键词： Axial flow compressor Surge rotating stall Coexisting state of surge and rotating stall

Numerical Investigation of rotating stall in Centrifugal Compressor with Vaned and Vaneless Diffuser

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Journal of Thermal Science 2015年第4期24卷 323-333页

作者： Taher Halawa Mohamed Alqaradawi Mohamed S.Gadala Ibrahim Shahin Osama Badr Mechanical Engineering Department UBC-University of British ColumbiaVancouverB.C.Canada Mechanical Engineering Department Cairo University Mechanical & Industrial Engineering Department Qatar University Mechanical Engineering Department Abu Dhabi University Mechanical and Industrial Engineering Department Qatar UniversityDohaQatar Mechanical Engineering Department Benha University Mechanical Engineering Department British University

This study presents a numerical simulation of the stall and surge in a centrifugal compressor and presents a description of the stall development in two different *** first case is for a compressor with vaneless diffuser and the second is for a compressor with vaned diffuser of the vane island *** main aim of this study is to compare the flow characteristics and behavior for the two compressors near the surge operating condition and provide further understanding of the diffuser role when back flow occurs at *** showed that for a location near the diffuser entrance,the amplitude of the static pressure fluctuations for the vaneless diffuser case is higher than that for the vaned diffuser case near surge *** pressure fluctuations in the case of the vaneless diffuser appear with a gradual decrease of the mean pressure value as a part of the surge *** for the case of the vaned diffuser,the pressure drop during surge occurs faster than the case of the vaneless ***,results indicated that during surge in the case of vaneless diffuser,there is a region with low velocity and back flow that appears as a layer connecting all impeller passages near shroud surface and this layer develops in size with *** the other hand,for the case of vaned diffuser during surge,the low velocity regions appear in random locations in some passages and these regions expand with time towards the shroud *** showed that during stall,the impeller passages are exposed to identical impact from stall cells in the case of vaneless diffuser while the stall effect varies from passage to another in the case of the vaned diffuser.

关键词： centrifugal compressors rotating stall surge vaneless diffuser vaned diffuser

Study of rotating stall in a Centrifugal Compressor with Wide Vaneless Diffuser

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Journal of Thermal Science 2020年第3期29卷 743-752页

作者： ZHANG Lei ZHENG Zhi ZHANG Qian ZHANG Liang LI Kang Department of Power Engineering North China Electric Power UniversityBaoding 071003China

To study the stall mechanism in a wide vaneless diffuser,a three-dimensional centrifugal compressor model was *** numerical simulation method was used to study the fluid characteristics in a centrifugal compressor with a wide vaneless diffuser under stall *** simulated results showed that the wide vaneless diffuser stall was related to the instability of the core *** to the influence of the reflow,the core flows moved between the hub and shroud side and the directions were not *** was called core flow distortion,which triggered the rotating *** reflow first appeared at the outlet boundary of the diffuser,and the reflux gradually expanded to the inside of the diffuser as the impeller ***,the reflux zones grew and merged,forming a stable low-speed fluid regiment,which produced a stall *** stall cells rotated around themselves with an opposite direction with impeller.

关键词： centrifugal compressor wide vaneless diffuser rotating stall numerical simulation

Hysteresis behaviors of compressor rotating stall with cusp catastrophic model

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Chinese Journal of Aeronautics 2018年第5期31卷 1075-1084页

作者： Zhiping LI Peng ZHANG Tianyu PAN Qiushi LI Jian ZHANG National Key Laboratory of Science and Technology on Aero-Engine Aerothermodynamics Beihang University Collaborative Innovation Center of Advanced Aero-Engine Beihang University School of Energy and Power Engineering Beihang University Department of Mechanical Engineering and Materials Science Duke University

rotating stall is a complex nonlinear dynamic phenomenon which is always characterized by catastrophe and hysteresis in high aerodynamic-loading compressor. Exploring the key contributing factors and characteristic rules of hysteresis is very important for compressor design and flow instability control. In this paper, a novel model method is proposed to analyze the hysteresis behaviors to extend the understanding of compressor rotating stall. The equilibrium states of compressor system under different conditions are first described based on Moore-Greitzer model. Then,through assessing the stability of the equilibrium points by Liapunov＇s theorem, the ratio of shutoff head to compressor characteristic semi-height is found to affect the stall hysteresis： the size of hysteresis loop will gradually decrease, even disappear with the increase of the ratio. Combing the effects of both the ratio and throttle coefficient, the hysteresis behaviors of compressor stall under multi-parameters can be found to be consistent with the topological properties of cusp catastrophic model by Thom＇s catastrophe theory. Finally, according to topological invariant rules, from the perspective of potential function, the equilibrium surface equation of compressor system is developed by standard cusp catastrophic model to describe the various hysteresis behaviors of compressor rotating stall along different control routes.

关键词： Catastrophe theory Compressor Hysteresis rotating stall Topological analysis

Unsteady Flow Field under Surge and rotating stall in a Three-stage Axial Flow Compressor

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Journal of Thermal Science 2011年第1期20卷 6-12页

作者： Takayuki HARA Daisuke MORITA Yutaka OHTA Eisuke OUTA Graduate Student Graduate school of Science and EngineeringWaseda University3-4-1 OkuboShinjukuTokyo 169-8555Japan Department of Applied Mechanics and Aerospace Engineering Waseda University3-4-1 OkuboShinjukuTokyo 169-8555Japan

The unsteady flow structure between rotor blade-to-blade passages in a three-stage axial flow compressor is experimentally investigated by detailed measurements of unsteady performance characteristics,casing wall pressure fluctuations and their wavelet *** main feature of the test compressor is a capacity tank facility connected in series to the compressor outlet in order to supply compression and/or expansion waves from downstream of the *** attention is focused on the post-stall characteristics of the surge and rotating stall which occur *** influence of the compressor operating point on the unsteady performance curve shows that the surge cycle changes irregularly depending on the steady-state resistance characteristics,and the results of the wavelet analyses of the wall pressure fluctuations suggest that the surge cycle may selectively be determined by the rotating stall cell structure within the rotor cascade.

关键词： Axial flow compressor Surge rotating stall stall cell Wavelet analysis.

EXPERIMENTAL INVESTIGATION OF rotating stall FOR A LOW-SPEED CENTRIFUGAL COMPRESSOR

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Chinese Journal of Mechanical Engineering 2008年第3期21卷 76-83页

作者： ZHU Xiaocheng GUO Qiang DU Zhaohui CHEN Hua ZHAO Yan School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China Honeywell Corporation Shanghai 200030 China

Unsteady flows and rotating stall of a low-speed centrifugal compressor are investigated by measuring vaneless diffuser wall static pressure fluctuation and internal flow fields at different small flow fluxes. During the experiment, firstly the real time static pressure fluctuations on the vaneless diffuser shroud at different circumferential and radial position were acquired by high-frequency dynamic pressure transducers. Discrete Fourier transformation analysis and cross-correlation analysis were applied to the experimental results to ascertain the rotating stall beginning operation conditions and stall cells numbers and rotating speed. Secondly, the vaneless diffuser inlet flow angle distribution along diffuser width direction was acquired by single hotwire, which was compared with SENOO＇s analysis results. At last, the internal flow fields of the centrifugal compressor were investigated with a particle image velocimetry （PIV） system at different small flow fluxes. The flow field development of vaneless diffuser and blade flow passage are given at rotating stall conditions. The experiments enrich the understanding of rotating stall flow phenomenon of the low-speed centrifugal compressor and provide full experiment data for designing high performance centrifugal compressor.

关键词： rotating stall Centrifugal compressor Vaneless diffuser Particle image velocimetry (PIV)

Numerical Simulation of rotating stall in a Centrifugal Compressor with Vaned Diffuser

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Journal of Thermal Science 2007年第2期16卷 115-120页

作者： Weiguang Huang Shaojuan Geng Junqiang Zhu Hongwu Zhang Institute of Engineering Thermophysics Chinese Academy of Sciences EO. Box 2706 Beijing 100080 China Graduate School of the Chinese Academy of Sciences

This paper reports a numerical study on the process from normal operating conditions to rotating stall in a centrifugal compressor with vaned diffuser. The purpose is to better understand the flow characteristics near stall point under the interactions between centrifugal impeller and vaned diffuser. Numerical results show that under certain conditions just preceding stall point the tip leakage vortex begins to fluctuate at roughly half of the blade passing frequency. This phenomenon is similar to rotating instability in axial compressors. With the flow rate reduced further the impeller stalls and five stall cells propagating at a frequency of 85 percent of impeller rotation speed are found.

关键词： centrifugal compressor rotating stall tip leakage flow unsteady.

Experimental Investigations of Micro Air Injection to Control rotating stall

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Journal of Thermal Science 2007年第1期16卷 1-6页

作者： Chaoqun Nie Zhiting Tong Shaojuan Geng Junqiang Zhu Weiguang Huang Institute of Engineering Thermophysics Chinese Academy of Sciences EO. Box 2706 Beijing 10080 China Graduate School of the Chinese Academy of Sciences

Steady discrete micro air injection at the tip region in front of the first compressor rotor has been proved to be an effective method to delay the inception of rotating stall in a low speed axial compressor. Considering the practical application a new type of micro injector was designed and described in this paper, which was imbedded in the casing and could be moved along the chord. In order to verify its feasibility to other cases, such as high subsonic axial compressor or centrifugal compressor, some other cases have been studied. Experimental results of the same low speed axial compressor showed that the new injector could possess many other advantages besides successfully stabilizing the compressor. Experiments performed on a high subsonic axial compressor confirmed the effectiveness of micro air injection when the relative velocity at the blade tip is high subsonic. Meanwhile in order to explore its feasibility in centrifugal compressor, a similar micro injector was designed and tested on a low speed centrifugal compressor with vaned diffuser. The injected mass flow was a bit larger than that used in axial compressors and the results showed micro injection could also delay the onset of rotating stall in the centrifugal compressor.

关键词： compressor rotating stall air injection