Artykuły w czasopismach: „Stall and Surge”

1

Akhlaghi, Mohammad, Yahya Azizi i Nourouz Mohammad Nouri. "Estimations of Compressor Stall and Surge Using Passage Stall Behaviors". Machines 10, nr 8 (18.08.2022): 706. http://dx.doi.org/10.3390/machines10080706.

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The predictions of the onset of rotating stall and surge are very important in the preliminary design stage of a compressor. Rotating stall and surge are complex instabilities that cause efficiency loss and reduced pressure rise, and, therefore, compressor designers attempt to avoid them in the design stage. There are many criteria for predicting stability limits, including empirical, theoretical, and numerical investigations in the literature. However, these investigations have important limitations. The present study establishes a new method in which the stall and post-stall behavior of a compressor is estimated by an equivalent reconstructed compressor using special combinations of single-passage flow behavior in different mass flow rates. The combinations are generated such that pre-stall, in-stall, and surge flow regimes and between one and eight stall cells are reproduced in the full-annulus compressor. The method requires the least computational requirements and is time efficient. The results indicate that secondary flow total energy and spectral entropy are indeed correlated with compressor operating conditions. The predictions of the onset of stall and surge for the investigated compressor show good agreement with the experimental data.

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Chattopadhyay, N. C., H. E. M. Zahidul Islam Eunus, Md Imtiaz Ikram i Roohany Mahmud. "Compressor Instability: Stall, Surge and their Control". Applied Mechanics and Materials 390 (sierpień 2013): 408–13. http://dx.doi.org/10.4028/www.scientific.net/amm.390.408.

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Every compressor has a stall line. In the vicinity of the stall line, the flow field is inherently unsteady due to the interactions between adjacent rows of blades, formation of small stall cells, flow separation and the viscous effects including shock-boundary layer interactions. These factors may aggravate to a state of local breakdown of flow or a total breakdown of flow or with a disastrous flow reversal. This paper starts with an overview on the previous researches about compressor stall and surge. Subsequently, it describes the effects of these instabilities in overall engine performance and design with/ without any control. The main objectives of this paper are to review the phenomenon of instability and methodology to suppress the rotating stall and surge by enlarging the stable operating range of compressor with the application of various control systems. This paper surveys research developments in this field and also tries to find an improved solution to increase the engine performance by applying various surge control strategies. Finally, the paper focuses on some recommendations towards a better design of compressor especially for aircraft power plant.

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Wilson, A. G., i C. Freeman. "Stall Inception and Development in an Axial Flow Aeroengine". Journal of Turbomachinery 116, nr 2 (1.04.1994): 216–25. http://dx.doi.org/10.1115/1.2928356.

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This paper describes the phenomenon of stall and surge in an axial flow aeroengine using fast response static pressure measurements from the compressor of a Rolls-Royce VIPER engine. It details the growth of flow instability at various speeds, from a small zone of stalled fluid involving only a few blades into the violent surge motion of the entire machine. Various observations from earlier theoretical and compressor rig results are confirmed by these new engine measurements. The main findings are as follows: (1) The point of stall inception moves rearward as engine speed increases, and is shown to be simply related to the axial matching of the compressor. (2) The final unstable operation of the machine can be divided into rotating stall at low speed and surge or multiple surge at high speed. (3) The inception process is independent of whether the final unstable operation is rotating stall or multiple surge. (4) Stall/surge always starts as a circumferentially small flow disturbance, rotating around the annulus at some fraction of rotor speed.

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Hickman, Adam R., i Scott C. Morris. "Observations of the Growth and Decay of Stall Cells during Stall and Surge in an Axial Compressor". International Journal of Rotating Machinery 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/6329382.

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This research investigated unsteady events such as stall inception, stall-cell development, and surge. Stall is characterized by a decrease in overall pressure rise and nonaxisymmetric throughflow. Compressor stall can lead to surge which is characterized by quasi-axisymmetric fluctuations in mass flow and pressure. Unsteady measurements of the flow field around the compressor rotor are examined. During the stall inception process, initial disturbances were found within the rotor passage near the tip region. As the stall cell develops, blade lift and pressure ratio decrease within the stall cell and increase ahead of the stall cell. The stall inception event, stall-cell development, and stall recovery event were found to be nearly identical for stable rotating stall and surge cases. As the stall cell grows, the leading edge of the cell will rotate at a higher rate than the trailing edge in the rotor frame. The opposite occurs during stall recovery. The trailing edge of the stall cell will rotate at the approximate speed as the fully developed stall cell, while the leading edge decreases in rotational speed in the rotor frame.

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5

Day, I. J. "Active Suppression of Rotating Stall and Surge in Axial Compressors". Journal of Turbomachinery 115, nr 1 (1.01.1993): 40–47. http://dx.doi.org/10.1115/1.2929216.

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This paper reports on an experimental program in which active control was successfully applied to both rotating stall and surge in a multistage compressor. Two distinctly different methods were used to delay the onset of rotating stall in a four-stage compressor using fast-acting air injection valves. The amount of air injected was small compared to the machine mass flow, the maximum being less than 1.0 percent. In some compressor configurations modal perturbations were observed prior to stall. By using the air injection valves to damp out these perturbations, an improvement of about 4.0 percent in stall margin was achieved. The second method of stall suppression was to remove emerging stall cells by injecting air in their immediate vicinity. Doing this repeatedly delayed the onset of stall, giving a stall margin improvement of about 6.0 percent. Further studies were conducted using a large plenum downstream of the compressor to induce the system to surge rather than stall. The resulting surge cycles were all found to be initiated by rotating stall and therefore the stall suppression systems mentioned above could also be used to suppress surge. In addition, it was possible to arrest the cyclical pulsing of a compressor already in surge.

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Mizuki, S., i Y. Oosawa. "Unsteady Flow Within Centrifugal Compressor Channels Under Rotating Stall and Surge". Journal of Turbomachinery 114, nr 2 (1.04.1992): 312–20. http://dx.doi.org/10.1115/1.2929145.

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Unsteady flow patterns throughout a centrifugal compressor system during the rotating stall and the surge were measured experimentally. Various kinds of unsteady behavior of the flow appeared both continuously and suddenly as the flow rate decreased. The part-span stall, the full-span stall, the mild and deep stalls, and the deep surge appeared clearly. The fluctuations caused by the full-span stall were seen even during surge and affected the flow within the scroll through the vaneless diffuser. The experimental results were compared with those computed by the lumped parameter theory. Good agreements between them were obtained when appropriate values were selected for the lumped parameters.

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7

Coller, B. D. "Hopf-Hopf Interactions of Surge and Rotating Stall". Journal of Computational and Nonlinear Dynamics 1, nr 4 (6.06.2006): 320–27. http://dx.doi.org/10.1115/1.2338324.

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In this paper, we examine the interaction of two instabilities that occur in axial compressors using the Hopf-Hopf normal form. As a result, we illuminate some gaps in understanding the dynamics of standard compressor models. We find a possible dynamic mechanism, which explains certain “curious” behavior observed in experiments, and are able to predict and explain failure mechanisms in previously proposed control strategies.

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8

Hönen, H. "Axial Compressor Stall and Surge Prediction by Measurements". International Journal of Rotating Machinery 5, nr 2 (1999): 77–87. http://dx.doi.org/10.1155/s1023621x9900007x.

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The paper deals with experimental investigations and analyses of unsteady pressure distributions in different axial compressors. Based on measurements in a single stage research compressor the influence of increasing aerodynamic load onto the pressure and velocity fluctuations is demonstrated. Detailed measurements in a 14-stage and a 17-stage gas turbine compressor are reported. For both compressors parameters could be found which are clearly influenced by the aerodynamic load.For the 14-stage compressor the principles for the monitoring of aerodynamic load and stall are reported. Results derived from a monitoring system for multi stage compressors based on these principles are demonstrated. For the 17-stage compressor the data enhancement of the measuring signals is shown. The parameters derived from these results provide a good base for the development of another prediction method for the compressor stability limit. In order design an on-line system the classification of the operating and load conditions is provided by a neural net. The training results of the net show a good agreement with different experiments.

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9

Eveker, K. M., D. L. Gysling, C. N. Nett i O. P. Sharma. "Integrated Control of Rotating Stall and Surge in High-Speed Multistage Compression Systems". Journal of Turbomachinery 120, nr 3 (1.07.1998): 440–45. http://dx.doi.org/10.1115/1.2841735.

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Aeroengines operate in regimes for which both rotating stall and surge impose low-flow operability limits. Thus, active control strategies designed to enhance operability of aeroengines must address both rotating stall and surge as well as their interaction. In this paper, a previously developed nonlinear control strategy that achieves simultaneous active control of rotating stall and surge is applied to a high-speed three-stage axial flow compression system with operating parameters representative of modern aeroengines. The controller is experimentally validated for two compressor builds and its robustness to radial distortion assessed. For actuation, the control strategy utilizes an annulus-averaged bleed valve with bandwidth on the order of the rotor frequency. For sensing, measurements of the circumferential asymmetry and annulus-averaged unsteadiness of the flow through the compressor are used. Experimental validation of simultaneous control of rotating stall and surge in a high-speed environment with minimal sensing and actuation requirements is viewed as another important step toward applying active control to enhance operability of compression systems in modern aeroengines.

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10

Langston, Lee S. "Out Through the Intake". Mechanical Engineering 139, nr 04 (1.04.2017): 36–41. http://dx.doi.org/10.1115/1.2017-apr-2.

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This article elaborates various challenges presented by stall and surge to the gas turbine research community and jet engine designers. The article also presents several examples of stall and surge faced by the pilots. Stall and surge emerge from basic physics: the behavior of the boundary layer on the compressor blades and stators; however, current technology has no means to completely eliminate it. Engine control systems, such as the Full Authority Digital Electric Control (FADEC), are programmed to keep the operating point of the compressor well away from the surge line. Researchers have been studying stall and surge for decades, looking for ways to predict and combat the phenomena. Meanwhile, there has been some success in using FADEC to either prevent a stall and surge or to limit the number of repetitions. FADEC can also step in during flights in heavy rain or hailstorms. In those conditions, extra fuel is needed to process and evaporate the water being swallowed by the engine. The electronic control system can sense the mismatch between the power setting and the fuel flow and take action to prevent possible engine instability.

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11

Čudina, M. "Noise generation in vane axial fans due to rotating stall and surge". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 215, nr 1 (1.01.2001): 57–64. http://dx.doi.org/10.1243/0954406011520517.

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A characteristic of axial flow fans is instabilities in their performance and noise in partial load operation. These instabilities are a consequence of rotating stall created in the rotor blade and/or in the guide vane cascade. At some operating conditions the rotating stall caused the appearance of a surge representing the lowest region of fan operating stability. The rotating stall and especially surge caused a steep increase in the emitted noise and lowered the performance of the fan. The present paper highlights the rotating stall generation phenomenon and its influence on the emitted total noise level and noise spectra for axial flow fans with inlet and outlet guide vanes.

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12

XUE, Xiang. "Identification of Stall and Surge in Centrifugal Compressor Experiments". Journal of Mechanical Engineering 54, nr 18 (2018): 226. http://dx.doi.org/10.3901/jme.2018.18.226.

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Yenchev, Serhii, i Serhii Taku. "Ідентифікатор передпомпажних станів компресора авіаційного ГТД". Aerospace Technic and Technology, nr 5 (24.10.2022): 61–67. http://dx.doi.org/10.32620/aktt.2022.5.05.

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Surging is a dangerous operating mode of the compressor; in this mode, destabilization and flow stall occur, causing intense pressure fluctuations of the working fluid in the flow path or gas-dynamic shocks. Surging phenomena in gas turbine engines lead to a loss of thrust, are accompanied by an increase in the temperature of gases in front of the turbine and an increase in the level of vibration because of large amplitudes of pressure pulsations and mass flow rates along the engine path. The possibility of occurrence of these phenomena is a serious obstacle to increasing the reliability of gas turbine engines, including flight safety in general. The study of non-stationary processes in compressors shows that surge is preceded by such phenomena as pre-surge and rotating stall, which are called the pre-surge state of an aircraft GTE compressor. The study aims to develop informative criteria for the timely detection of the pre-surge state of the compressor of an aircraft gas turbine engine and to build an anti-surge algorithm for the functioning of the proposed identifier based on the developed criteria. To assess the stability of pressure pulsation periodicities, it is proposed to process and compare the signals received from fast-response sensors located in the compressor. In this article, informative criteria are formed for identifying the pre-surge state of an aircraft GTE compressor. The first criterion is the level of stability of the periodic component of pressure fluctuations. The second criterion is the limit of the relative range of pressure pulsations in the compressor. With the help of the obtained criteria, the pre-surge area is divided into pre-surge, weak stall, and intense stall. Such detailing makes it possible to prevent erroneous wear (in high-cost modes) and premature wear (in case of non-intensive disruption) of the anti-surge control system. Based on the criteria obtained, an algorithm for anti-surge adjustment was developed, according to which the anti-surge system is prepared for testing when a pre-surge or weak stall occurs in the compressor flow path, and is triggered when an intense stall occurs. Based on the anti-surge algorithm, a scheme for identifying the pre-surge states of an aircraft GTE compressor is proposed in the form of a three-level alarm and protection system. Recommendations for the practical implementation of the identifier are described.

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Ji, Jiajia, Jun Hu, Shuai Ma i Rong Xu. "A Computational Method of Rotating Stall and Surge Transients in Axial Compressor". Energies 15, nr 14 (20.07.2022): 5246. http://dx.doi.org/10.3390/en15145246.

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The onset of rotating stall and surge in compressors limits the operating range of aero-engines. Accurately predicting the key features during these events is critical in the engine design process. In this paper, a three-dimensional computational model for transient simulation of multi-stage axial compressors during stall is proposed. The kinetic equations describing the dynamic process of the compression system are constructed, with a 3D through-flow model for the compression part and a 1D gas collector model for the outlet part. The calculation of the source term is performed using the developed body-force model, which realizes the correlation between the deviation angle and the loss coefficient with the inlet parameters in various flow regions. Validated on a single-stage compressor and a single-rotor fan, the results show that the method is capable of capturing the stall and surge features correctly and that the three-dimensional structure of the stall cell can be captured. In addition, this model could be used for the analysis of the surge load, which is significant for the structural integrity of the compressor.

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Sun, Fengyong, i Haibo Zhang. "A research on the compressor blade tip pressure modeling and stall detection measure". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 230, nr 14 (6.08.2016): 2654–60. http://dx.doi.org/10.1177/0954410016629703.

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A new compressor rotational stall detection algorithm is proposed in this paper, and a well monotonicity exists in the correlation coefficient calculated by the algorithm and compressor surge margin. In order to reconstruct the compressor blade pressure, a trustworthy digital compressor blade pressure model is built. Specially, the model consists of three sub-models, the blade duct pressure model, rotational stall pulsation pressure model, and corrected rotational stall damping model. Simulation results indicate the effectiveness of the stall detection algorithm and compressor stochastic pressure model, which means that the correlation coefficient calculated from the algorithm and stochastic pressure model has a high reliability to take the place of surge margin as the flag of compressor stability.

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Abed, E. H., P. K. Houpt i W. M. Hosny. "Bifurcation Analysis of Surge and Rotating Stall in Axial Flow Compressors". Journal of Turbomachinery 115, nr 4 (1.10.1993): 817–24. http://dx.doi.org/10.1115/1.2929320.

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The surge and rotating stall post-instability behaviors of axial flow compressors are investigated from a bifurcation-theoretic perspective, using a model and system data presented by Greitzer (1976a). For this model, a sequence of local and global bifurcations of the nonliner system dynamics is uncovered. This includes a global bifurcation of a pair of large-amplitude periodic solutions. Resulting from this bifurcation are a stable oscillation (“surge”) and an unstable oscillation (“anti-surge”). The latter oscillation is found to have a deciding significance regarding the particular post-instability behavior experienced by the compressor. These results are used to reconstruct Greitzer’s (1976b) findings regarding the manner in which post-instability behavior depends on system parameters. Although the model does not directly reflect nonaxisymmetric dynamics, use of a steady-state compressor characteristic approximating the measured characteristic of Greitzer (1976a) is found to result in conclusions that compare well with observation. Thus, the paper gives a convenient and simple explanation of the boundary between surge and rotating stall behaviors, without the use of more intricate models and analyses including nonaxisymmetric flow dynamics.

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Ananthkrishnan, N., U. G. Vaidya i V. W. Walimbe. "Global stability and control analysis of axial compressor stall and surge phenomena using bifurcation methods". Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 217, nr 3 (1.01.2003): 279–86. http://dx.doi.org/10.1243/095765003322066501.

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Active controllers that allow the compressor to operate safely at its peak pressure rise point by preventing surge and controlling entry into rotating stall need to be globally stabilizing. Bifurcation methods have emerged as a useful tool for the analysis of global stability and control of nonlinear dynamical systems such as the axial compressor. In this paper we show how bifurcation analysis can be used effectively to obtain answers to questions of global stability of the compressor dynamics. Since the bifurcation method does not directly provide information on transient behaviour, we demonstrate how bifurcation results need to be carefully interpreted to be of use when dealing with practical systems. We then present a novel nonlinear bifurcation-based stall/surge controller that is globally stabilizing. With such a controller, it becomes possible to avoid surge entirely and to prevent abrupt entry into rotating stall. The controller also eliminates the hysteresis between entry into and recovery from a rotating stall, and maintains system stability under all perturbations, small and large.

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Pan, Tianyu, Haihui Wang i Qiushi Li. "An adaptive logarithmic threshold framelet analysis of the partial surge initiated instability in a transonic axial flow compressor". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 231, nr 17 (11.04.2016): 3202–13. http://dx.doi.org/10.1177/0954406216643560.

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Partial surge is a new type of instability inception in transonic axial flow compressors and occurs in the form of axisymmetric low-frequency disturbances localized in the hub region. The frequency of partial surge is about 12.5 Hz at 88% of the design rotor speed, while the frequency of developed rotating stall cells in the final phase of the evolution is around 190 Hz. As there are two different frequencies in the instability evolution of partial surge, it is difficult to well denoise the experimental data by general data processing methods that are focused on one single frequency. Considering the unique feature of the partial surge initiated instability, an adaptive logarithmic threshold framelet method has been built. By this method, the well-denoised results can be obtained. Based on the results, the instability evolution of partial surge is clearly shown. At the same time, several new findings about partial surge have been presented: (1) the propagating procedure of one partial surge disturbance: the amplitude of disturbance is increasing until one partial surge disturbance is developed; (2) the occurrence of rotating stall cells is related to the partial surge disturbance; (3) the propagating procedure of one rotating stall cell is presented; (4) the partial surge disturbance is well proved to be axisymmetric. Finally, the capability of this denoise method is also discussed.

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Fink, D. A., N. A. Cumpsty i E. M. Greitzer. "Surge Dynamics in a Free-Spool Centrifugal Compressor System". Journal of Turbomachinery 114, nr 2 (1.04.1992): 321–32. http://dx.doi.org/10.1115/1.2929146.

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Turbocharger surge has been investigated in a radial impeller-vaneless diffuser free-spool system. Several different aspects are addressed. First, two very different compression systems, one with a large downstream volume and one with the smallest possible downstream volume, are employed to examine stall initiation phenomena as well as the behavior of the compressor characteristics when operating in surge. The measurements show impeller stall at the inducer tips to be a key phenomena in initiating surge. The inducer stall is stationary and asymmetric, due to the presence of the volute, and is most severe near the volute tongue angular position. The compressor characteristic in the large volume system (which gave surge) is observed to be flatter and to lag that in the stabilized small volume system. The difference arises because of the slow development time and differing circumferential extent of the inducer stall present at a given mass flow. A nonlinear simulation of the system is also presented. The model deviates from previous treatments of unsteady flow in compressor systems in that the assumption of constant rotor speed is relaxed. Including a time lag on the order of the compressor throughflow time, together with proper treatment of speed variations, is shown to improve agreement with the observed surge behavior dramatically.

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Kirn, Kuk H., i Sanford Fleeter. "Compressor unsteady aerodynamic response to rotating stall and surge excitations". Journal of Propulsion and Power 10, nr 5 (wrzesień 1994): 698–708. http://dx.doi.org/10.2514/3.23782.

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Lorenzo, Carl F., Francis P. Chiaramonte i Charles M. Mehalic. "Determination of compressor in-stall characteristics from engine surge transients". Journal of Propulsion and Power 4, nr 2 (marzec 1988): 133–43. http://dx.doi.org/10.2514/3.23041.

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Guzel’baev, Ya Z., A. L. Khavkin i I. G. Khisameev. "Methods of rotating stall and surge detection in centrifugal compressors". Chemical and Petroleum Engineering 42, nr 5-6 (maj 2006): 320–26. http://dx.doi.org/10.1007/s10556-006-0101-6.

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Copeland, George Scott. "Reduced-order DAE models for turbomachinery stall, surge, and flutter". ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik 78, S3 (1998): 883–84. http://dx.doi.org/10.1002/zamm.19980781515.

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Sundström, Elias, Bernhard Semlitsch i Mihai Mihăescu. "Generation Mechanisms of Rotating Stall and Surge in Centrifugal Compressors". Flow, Turbulence and Combustion 100, nr 3 (23.11.2017): 705–19. http://dx.doi.org/10.1007/s10494-017-9877-z.

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Greitzer, E. M., i F. K. Moore. "A Theory of Post-Stall Transients in Axial Compression Systems: Part II—Application". Journal of Engineering for Gas Turbines and Power 108, nr 2 (1.04.1986): 231–39. http://dx.doi.org/10.1115/1.3239893.

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Using the theory developed in Part I, calculations have been carried out to show the evolution of the mass flow, pressure rise, and rotating-stall cell amplitude during compression system post-stall transients. In particular, it is shown that the unsteady growth or decay of the stall cell can have a significant effect on the instantaneous compressor pumping characteristic and hence on the overall system behavior. A limited parametric study is carried out to illustrate the impact of different system features on transient behavior. It is shown, for example, that the ultimate mode of system response, surge or stable rotating stall, depends not only on the B parameter, but also on the compressor length-to-radius ratio. Small values of the latter quantity tend to favor the occurrence of surge, as do large values of B. Based on the analytical and numerical results, some specific topics are suggested for future research on post-stall transients.

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Mirzaee, Saeed, Xinqian Zheng i Yun Lin. "Improvement in the stability of a turbocharger centrifugal compressor by tip leakage control". Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 231, nr 5 (18.07.2016): 700–714. http://dx.doi.org/10.1177/0954407016656543.

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The occurrence of surge or stall in a centrifugal compressor and the role of the tip clearance flow in the instability in the centrifugal compressor are investigated in this study. A computational method is used to study the flow field in the centrifugal compressor in order to gain a better understanding of the surge or stall mechanism. It is found that, near surge or stall conditions, the tip leakage flow at the leading edge deflects more upstream; as the deflection increases, a more severe spillage occurs which finally leads to instability of the compressor. A ring air jet injection is used to eliminate the instabilities and to extend the stable flow range of the compressor. Using an air jet injection, the stable flow range of the compressor was successfully increased with minimal decrease in the efficiency of the compressor. The effects of different injection parameters such as the mass flow, the yaw angle, the injection angle, the slot width and the slot distance on the compressor flow field are studied, and an optimum design for the air jet injection is developed. Further investigation of the compressor with the optimum injection configuration shows that, near surge or stall conditions, the tip leakage at the leading edge is still under control, manifesting a much smaller spillage than does the Dresser–Rand Datum compressor without an air injection. The dominant factor for the instability of the compressor with an injection is found to be the leading-edge separation rather than the tip leakage.

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Wernet, Mark P., Michelle M. Bright i Gary J. Skoch. "An Investigation of Surge in a High-Speed Centrifugal Compressor Using Digital PIV". Journal of Turbomachinery 123, nr 2 (1.01.2000): 418–28. http://dx.doi.org/10.1115/1.1343465.

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Compressor stall is a catastrophic breakdown of the flow in a compressor, which can lead to a loss of engine power, large pressure transients in the inlet/nacelle, and engine flameout. The implementation of active or passive strategies for controlling rotating stall and surge can significantly extend the stable operating range of a compressor without substantially sacrificing performance. It is crucial to identify the dynamic changes occurring in the flow field prior to rotating stall and surge in order to control these events successfully. Generally, pressure transducer measurements are made to capture the transient response of a compressor prior to rotating stall. In this investigation, Digital Particle Imaging Velocimetry (DPIV) is used in conjunction with dynamic pressure transducers to capture transient velocity and pressure measurements simultaneously in the nonstationary flow field during compressor surge. DPIV is an instantaneous, planar measurement technique that is ideally suited for studying transient flow phenomena in high-speed turbomachinery and has been used previously to map the stable operating point flow field in the diffuser of a high-speed centrifugal compressor. Through the acquisition of both DPIV images and transient pressure data, the time evolution of the unsteady flow during surge is revealed.

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Chun, Guo, Wang Mingnian i Tang Zhaozhi. "A Study on Surge and Stall under the Interaction of Parallel Axial flow fan in Tunnel". Noise & Vibration Worldwide 42, nr 11 (grudzień 2011): 9–14. http://dx.doi.org/10.1260/0957-4565.42.11.9.

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In the ventilation design for tunnels above 10km, an axial flow fan of great power needs to be set in ventilation shafts. There are few provisions on the setting modes and less discussion of parallel axial flow fan mode in the Specifications for Design of Ventilation and Lighting of Highway Tunnels. All of these bring a lot of difficulties about the axial fan selection, layout and control design. There is no specialized research on axial flow fan for tunnels and no studies on surge and stall under the interaction of parallel axial flow fan in tunnel in spite of the more and more application of parallel axial flow fan. So, this paper conducts a study on surge and stall under the interaction of parallel axial flow fan in tunnels. Through the study on the operating principle and analysis of parallel axial flow fan, we can know that the noise will increase suddenly, which will in turn result in fan vibration and running instability once the stall occurs. When a fan surges, the air volume and pressure, the motor current will fluctuate sharply, which brings significantly increased vibration and noise. At the same time, the rotary blade and the shell are subject to considerable stress effects and the fan will possibly suffer from great damage. The surge will occur in the unstable zone of axial fan performance curve. The strong pulsation and periodic oscillation of the air flow will increase the noise, which is a serious damage to the fan. So an axial fan should avoid this zone in running. With two axial flow fans of the same power parallel, the mutual influence is not very great. Therefore this research will focus on the efficiency in the case of two fans with a high and a low power parallel. Stall will occur if the outside pressure is greater than the outlet pressure. Once the stall happens, the noise will increase suddenly, which will in turn result in fan vibration and running instability. When two fans parallel, i.e. when the power ratio of the parallel fans is over 5.3, the possibility of the small fan's stall is high, otherwise it is small. With regard to the running efficiency of parallel axial flow fans and the starting safety, it is better to parallel two fans, and the fans with adjustable movable vanes or frequency control or the ordinary nonadjustable fans can be used.

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Xiao-Hong Qiu, Xiao-Hong Qiu, Jia-Li Chen Xiao-Hong Qiu i Zi-Ying Ao Jia-Li Chen. "Stall Warning Algorithm of Axial Compressor Based on SSA-DBN". 電腦學刊 33, nr 3 (czerwiec 2022): 059–71. http://dx.doi.org/10.53106/199115992022063303005.

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<p>To solve the problem of stall warning for axial compressors, this paper proposes a stall warning algorithm based on the sparrow search algorithm, which optimizes the deep belief network. The deep belief network is trained by using deep learning to extract the FFT spectrum of compressor stall experiment data directly as the feature vector. To improve the accuracy of DBN classification, parameters of hidden layer nodes n and initial weights w of DBN were optimized by SSA algorithm, and stall warning algorithm model of SSA-DBN axial-flow compressor was established. The experimental results of the algorithms show that the stall data at each speed is at least 0.1～0.3s in advance for early warning. This method is 0.075~0.281s ahead of the various models from the past to the present, and noise is superimposed on the experimental data to verify the Robustness of the way, better surge warning margin performance, and engineering practicability. </p> <p> </p>

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30

Vepa, Ranjan. "Modelling and Quasilinear Control of Compressor Surge and Rotating Stall Vibrations". Mathematical Problems in Engineering 2010 (2010): 1–21. http://dx.doi.org/10.1155/2010/314172.

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An unsteady nonlinear and extended version of the Moore-Greitzer model is developed to facilitate the synthesis of a quasilinear stall vibration controller. The controller is synthesised in two steps. The first step defines the equilibrium point and ensures that the desired equilibrium point is stable. In the second step, the margin of stability at the equilibrium point is tuned or increased by an appropriate feedback of change in the mass flow rate about the steady mass flow rate at the compressor exit. The relatively simple and systematic non-linear modelling and linear controller synthesis approach adopted in this paper clearly highlights the main features on the controller that is capable of inhibiting compressor surge and rotating stall vibrations. Moreover, the method can be adopted for any axial compressor provided its steady-state compressor and throttle maps are known.

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31

Methling, Frank-Oliver, Horst Stoff i Frank Grauer. "The Pre-Stall Behavior of a 4-Stage Transonic Compressor and Stall Monitoring Based on Artificial Neural Networks". International Journal of Rotating Machinery 10, nr 5 (2004): 387–99. http://dx.doi.org/10.1155/s1023621x04000399.

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Current research concerned with the aerodynamic instability of compressors aims at an extension of the operating range of the compressor towards decreased massflow. In practice, a safety margin is maintained between operating point and stability limit to prevent the compressor from going into stall and surge. In this article, we analyze the behavior of a 4-stage transonic axial compressor before entering the unstable range and present an approach to identifying incipient surge and stall using artificial neural networks. This method is based on measurements of the unsteady static wall pressure in front of the first rotor.Analyzing the static pressure signals by using the Fast Fourier Transform shows that peripheral disturbances (modal waves) can only be identified in a small range close to nominal speed (at 95%). At lower speeds (60 to 80% of nominal speed), the investigated compressor flow enters instability by spike-type stall.Monitoring stability over the entire speed range of the compressor relies on artificial neural networks using the unsteady wall pressure signal. In the present case, artificial neural networks show to be the most useful tool to indicate approaching instability. The method works reliably for both types of instabilities, spike-type stall as well as modal waves.

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32

Ng, Eddie Yin-Kwee, Ningyu Liu i Shin Yi Tan. "Parametric Study of Greitzer's Instability Flow Model Through Compressor System Using the Taguchi Method". International Journal of Rotating Machinery 10, nr 2 (2004): 91–97. http://dx.doi.org/10.1155/s1023621x04000107.

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The occurrence of stall and surge is caused by instability of the flow through the compressor system. These two phenomena often result in serious mechanical problems for the compressor. The scope of this article includes a review and parametric study on the characteristics of stall and surge and their mathematical modeling.In this article, Greitzer's B-parameter model is applied for analyzing the stall and surge characteristics. Based on this model, a total of four parameters—B,G,K, andLC—in the model are highlighted in order to establish the influence of each parameter on the system. ParametersB,G, andKare all dimensionless constants whileLCis the effective length of the compressor duct.Here, the governing equations of stall and surge behavior are solved numerically using fourth-order Runge-Kutta method. The Taguchi method is then used to analyze the results generated to obtain the extent of effects of the parameters on the system by varying the parameters in a series of combinations. Finally, a thorough analysis is carried out on the results generated from the Taguchi method and the graphs. It is found that parameterKis the deciding factor in the position of the cross point whereas parameterBis the most important one in changing the length of time needed for the compressor to reach its steady state.

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33

Halawa, Taher, i Mohamed S. Gadala. "Numerical Investigation of Compressor Blades Deformation During Stall Development into Surge". Journal of Propulsion and Power 33, nr 5 (wrzesień 2017): 1074–86. http://dx.doi.org/10.2514/1.b36076.

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34

Yew-Wen Liang i Der-Cherng Liaw. "Detection of surge and stall in compression systems: an example study". IEEE Transactions on Automatic Control 46, nr 10 (2001): 1609–13. http://dx.doi.org/10.1109/9.956058.

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35

Cudina, Mirko. "Noise generation by rotating stall and surge in vane-axial fans". Noise Control Engineering Journal 48, nr 3 (2000): 77. http://dx.doi.org/10.3397/1.2827969.

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36

Sheng, Hanlin, Wei Huang i Tianhong Zhang. "Output Feedback Control of Surge and Rotating Stall in Axial Compressors". Asian Journal of Control 19, nr 2 (21.09.2016): 599–605. http://dx.doi.org/10.1002/asjc.1384.

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37

Sun, T., G. H. Xu i C. M. Zhang. "Study of the improved algorithm for correlation integral method and its application to surge precursor identification". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 222, nr 4 (1.04.2008): 657–66. http://dx.doi.org/10.1243/09544062jmes758.

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Correlation integral method (CIM) is a perfect method for the detection of stall and surge. However, CIM is very time-consuming due to its computational complexity. This paper aims to resolve the disadvantage. First, the segmented computation of correlation integral (CI) is deduced; second, the mapping criterion is given; finally the improved correlation integral method (ICIM) is proposed. The criterion can search the repeated subset of points and pair of subsets efficiently, which aids the ICIM in eliminating all redundancy caused by the overlapping of consecutive time windows. By applying ICIM to the detection of surge precursor in centrifugal compressors, it is illustrated that CI has a sharp decline more than 1.5 s prior to the fully developed surge. Also the processing time of ICIM is much shorter than that of CIM. The explicit detection of surge precursor, its rapid recognition, and the resulting longer time available for the feedback preventing the surge are the principal advantages of this approach. These studies are significant for CIM and will boost its application in numerous fields, especially in the detection of stall and surge.

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38

Ribi, B., i G. Gyarmathy. "Energy Input of a Centrifugal Stage Into the Attached Piping System During Mild Surge". Journal of Engineering for Gas Turbines and Power 121, nr 2 (1.04.1999): 325–34. http://dx.doi.org/10.1115/1.2817124.

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Subjected to an oscillating flow rate, a compressor may feed additional (excitational) energy into the attached piping system. The relation between this additional energy input and the instantaneous behavior of a centrifugal compressor stage is dealt in a first part. Modeling the stage behavior by taking into account either inertia of the enclosed fluid mass or a first-order transient element or transient stall in any component leads to a different energy input. The energy input at a flow rate oscillation of given frequency and amplitude was calculated as a function of the slope of the characteristic and the reduced frequency applying a previously published model to describe the instantaneous behavior of the stage. In this model transient stall in the diffuser is taken into account. At reduced frequencies above unity the energy input of the diffuser was reduced by a considerable amount due to the specified instantaneous behavior of the diffuser. This indicates a potential to reduce the additional energy input of the diffuser either by increasing the time constant of the stall process or by increasing the mild surge frequency. For the investigated diffuser size the required reduced frequencies imply mild surge frequencies in a range being too high for industrial application (>200 Hz). Still, this method turned out to give useful insight into the link between the instantaneous behavior of the compressor and its energy input. In a second part for the same centrifugal compressor the energy contribution of several stage segments during mild surge oscillations was determined from detailed instantaneous measurements. As a result, the contribution of each stage segment to the conservation of the mild surge pulsation emerges. Although at the investigated mild surge frequencies the stage segments no longer behave strictly quasi-steadily, their contribution to the additional energy input is found to be mainly determined by the slope of their quasi-steady characteristic.

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39

Niccolini Marmont Du Haut Champ, Carlo Alberto, Aristide Fausto Massardo, Mario Luigi Ferrari i Paolo Silvestri. "Surge prevention in gas turbines: an overview over historical solutions and perspectives about the future". E3S Web of Conferences 113 (2019): 02003. http://dx.doi.org/10.1051/e3sconf/201911302003.

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The aim of the present work is to retrace experimental, analytical and numerical analyses which deal with compressor instability phenomena, such as rotating stall and surge. While the first affects only the machine itself, the second involves the whole energy system. Surge onset is characterized by strong pressure and mass flow rate fluctuations which can even lead to reverse flow through the compressor. Experimental studies on prevention of axial compressor fluid dynamic instabilities, which can be propagated and eventually damage the solid structure, have been carried out by many authors. The first important studies on this topic tried to underline the main aspects of the complex detailed mechanism of surge, by replacing the compression system with an equivalent conceptual lumped parameter model. This is specially meant to capture the unsteady behaviour and the transient response of the compression system itself, particularly its dependence on variations in the volume of discharge downstream and in the settings of the throttle valve at its outlet (which simulates the actual load coupled to the compressor). Greitzer’s model is still regarded as the milestone for new investigations about active control and stabilization of surge and, more generally, about active suppression of aerodynamic instabilities in turbomachinery. During the last years, a lot of simulations and experimental studies about surge have been conducted on multistage centrifugal compressors with different architectures (e.g. equipped with vaneless or vaned diffusers). Moreover, further kinds of analysis try to extend the stable working zone of compressors, identifying stall and surge precursors extractable from information contained in the vibro-acoustical and rotodynamic response of the system.

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40

Giannissis, G. L., A. B. McKenzie i R. L. Elder. "Experimental Investigation of Rotating Stall in a Mismatched Three-Stage Axial Flow Compressor". Journal of Turbomachinery 111, nr 4 (1.10.1989): 418–25. http://dx.doi.org/10.1115/1.3262289.

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This paper reports on an examination of rotating stall in a low-speed three-stage axial flow compressor operating with various degrees of stage mismatch. The objective of this study was to simulate the mismatching that occurs in high-speed multistage compressors when operating near surge. The study of the stall zones involved the use of fast response measurement techniques. The study clearly shows how stages can operate in an axisymmetric fashion even when heavily stalled, since rotating stall inception requires the stall of more than one stage. The study also compares conditions required for full-span and part-span stall and suggests that the part-span stall structure is more relevant to high-speed multistage compressors.

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41

Arnulfi, G. L., P. Giannattasio, C. Giusto, A. F. Massardo, D. Micheli i P. Pinamonti. "Multistage Centrifugal Compressor Surge Analysis: Part I—Experimental Investigation". Journal of Turbomachinery 121, nr 2 (1.04.1999): 305–11. http://dx.doi.org/10.1115/1.2841315.

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This paper reports an experimental investigation on centrifugal compressor surge. The compression system consists of a four-stage blower with vaned diffusers and a large plenum discharging into the atmosphere through a throttle valve. Measurements of unsteady pressure and flow rate in the plant, and of instantaneous velocity in the diffusers of the first and fourth compressor stage, are performed during deep surge, at several valve settings and three different rotation speeds. Additional tests have been carried out on a different system configuration, i.e., without plenum, in order to obtain the steady-state compressor characteristics and to collect reference data on stall in surge-free conditions. In this configuration, a fully developed rotating stall was detected in the compressor diffusers, while during surge it affects only a limited part of the surge cycle. The goal of the present experimental work was to get a deeper insight into unstable operating conditions of multistage centrifugal compressors and to validate a theoretical model of the system instability to be used for the design of dynamic control systems.

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42

Spakovszky, Z. S. "Backward Traveling Rotating Stall Waves in Centrifugal Compressors". Journal of Turbomachinery 126, nr 1 (1.01.2004): 1–12. http://dx.doi.org/10.1115/1.1643382.

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Rotating stall waves that travel against the direction of rotor rotation are reported for the first time and a new, low-order analytical approach to model centrifugal compressor stability is introduced. The model is capable of dealing with unsteady radially swirling flows and the dynamic effects of impeller-diffuser component interaction as it occurs in centrifugal compression systems. A simple coupling criterion is developed from first principles to explain the interaction mechanism important for system stability. The model findings together with experimental data explain the mechanism for first-ever observed backward traveling rotating stall in centrifugal compressors with vaned diffusers. Based on the low-order model predictions, an air injection scheme between the impeller and the vaned diffuser is designed for the NASA Glenn CC3 high-speed centrifugal compressor. The steady air injection experiments show an increase of 25% in surge-margin with an injection mass flow of 0.5% of the compressor mass flow. In addition, it is experimentally demonstrated that this injection scheme is robust to impeller tip-clearance effects and that a reduced number of injectors can be applied for similar gains in surge-margin. The results presented in this paper firmly establish the connection between the experimentally observed dynamic phenomena in the NASA CC3 centrifugal compressor and a first principles based coupling criterion. In addition, guidelines are given for the design of centrifugal compressors with enhanced stability. Winner of the “Best Paper Award,” Turbomachinery Committee

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43

Xinqian, Zheng, i Liu Anxiong. "Experimental Investigation of Surge and Stall in a High-Speed Centrifugal Compressor". Journal of Propulsion and Power 31, nr 3 (maj 2015): 815–25. http://dx.doi.org/10.2514/1.b35448.

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Falugi, P., L. Giarréce, L. Chisci i G. Zappa. "LPV Predictive Control of the Stall and Surge for Jet Engine 1". IFAC Proceedings Volumes 34, nr 12 (sierpień 2001): 31–36. http://dx.doi.org/10.1016/s1474-6670(17)34057-0.

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45

Gu, G., A. Sparks i S. S. Banda. "An overview of rotating stall and surge control for axial flow compressors". IEEE Transactions on Control Systems Technology 7, nr 6 (1999): 639–47. http://dx.doi.org/10.1109/87.799664.

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46

Ohta, Yutaka, Yutaka Fujita i Daisuke Morita. "Unsteady behavior of surge and rotating stall in an axial flow compressor". Journal of Thermal Science 21, nr 4 (27.07.2012): 302–10. http://dx.doi.org/10.1007/s11630-012-0548-z.

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47

Abe, Takuya, Hiroaki Mitsui i Yutaka Ohta. "Coexisting phenomena of surge and rotating stall in an axial flow compressor". Journal of Thermal Science 22, nr 6 (13.11.2013): 547–54. http://dx.doi.org/10.1007/s11630-013-0661-7.

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48

Gerasimenko, Volodymyr, Vadym Datsenko i Mikhail Shevchenko. "CREATION OF AFTERBURNING TURBOFAN ENGINE – HISTORY AND PRESENT". Aerospace technic and technology, nr 5 (29.08.2020): 26–40. http://dx.doi.org/10.32620/aktt.2020.5.04.

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The main problems of the creation of afterburning turbofan engines, among which the irremovable surge of the compressor, is disclosed by historical analysis. According to the published models, such surge is a hydrodynamic instability in the form of rotating stall mutual transitions to surge with the primary cause of instability in the form of stall or vibration combustion in the afterburner. The Pratt & Whitney F100 serial engine, which based on TF30 is one of the first in which the irremovable surge was detected. As a result, several planes F-15 crashed, so far as the compressor could not be restored to a stable state without stopping and restarting the engine. Dissection of the problem with this phenomenon led to the conclusion that this irremovable surge problem was generated by the engine design. To eliminate it, the company had to refine several systems, such as an electronic engine control system, fuel supply of the afterburner along with the nozzle locations, firing belt, combustion stabilization, an extension of flow separation along the contours, etc. According to the analysis of publications, particular difficulties arose with the recoverable unsurge operation of such engines. It is noteworthy that today, the F-135-PW100 engines have been installed on the F-35 aircraft, the predecessors of which are the F-100 engines with the same problems. The results of experimental studies of a fan are presented in the article to deepen in the stall flow mechanism and the occurrence of rotating stall of the fan blades. The perturbations from vibrational combustion in the afterburner combustion chamber to the fan stall boundary in the afterburning turbofan engine system at bench conditions were simulated by independent throttling of the duct over a wide range of the bypass ratio. Numerous monographs and publications according to vibrational combustion, in particular in afterburner combustion chambers TRDF AL-21F and TRDDF AL-31F, of A. M. Lulka, confirm the possibility of the propagation of perturbations against the flow in the bypass duct and the impossibility of their propagation through the turbines. The propagation of surge perturbations in the afterburning turbofan engine to the compressor of the internal duct behind the fan occurs through the interaction of the duct. The more reliable way to prevent emergencies is to provide stability margin area of compressors. Estimation of the pre-stall state of the flow traditionally is carried out by the diffusivity factor of Lieblein FD, which is applicable in 2D calculations. The integral variational principle of nonequilibrium thermodynamics of the “maximum flow of mechanical energy” of V. N. Yershov was applied.

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49

Moënne-Loccoz, Victor, Isabelle Trébinjac, Nicolas Poujol i Pierre Duquesne. "Low frequency stall modes of a radial vaned diffuser flow". Mechanics & Industry 20, nr 8 (2019): 805. http://dx.doi.org/10.1051/meca/2020026.

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The present paper aims at providing an experimental analysis of the path to surge of a centrifugal compressor stage designed and built by Safran Helicopter Engines. Depending on the rotation speed of the compressor, two distinct flow patterns are observed in the radial diffuser at stabilized operating points near the surge, an asymmetric and a symmetric pattern. At medium rotation speed, the alternate pattern consisting of a two-channel pattern in the radial diffuser develops. One passage over two is stalled, the adjacent passage is free and this pattern replicates over the whole circumference while pulsing at a frequency of roughly 12 Hz which is close to the Helmholtz frequency of the test rig. By lowering the rotation speed, the two-channel pattern fades away and gives way to a periodical behavior of the radial diffuser passages called symmetric mode. The flow in each channel is identical presenting a stalled behavior pulsating in phase at a higher frequency of roughly 42 Hz. The two 12 Hz and 42 Hz modes are described and their existences are imputed to a lock-in of the natural frequencies of the instabilities with the acoustic modes of the test rig.

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50

Li, Yan-Ling, i Abdulnaser I. Sayma. "Computational fluid dynamics simulations of blade damage effect on the performance of a transonic axial compressor near stall". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 229, nr 12 (10.10.2014): 2242–60. http://dx.doi.org/10.1177/0954406214553828.

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Gas turbine axial compressor blades may encounter damage during service for various reasons such as damage by debris from casing or foreign objects impacting the blades, typically near the rotor’s tip. This may lead to deterioration of performance and reduction in the surge margin. The damage breaks the cyclic symmetry of the rotor assembly; thus, computational fluid dynamics simulations have to be performed using full annulus compressor assembly. Moreover, downstream boundary conditions are unknown during rotating stall or surge, and simulations become difficult. This paper presents unsteady computational fluid dynamics analyses of compressor performance with tip curl damage. Computations were performed near the stall boundary. The primary objectives are to understand the effect of the damage on the flow behaviour and compressor stability. Computations for the undamaged rotor assembly were also performed as a reference case. A transonic axial compressor rotor was used for the time-accurate numerical unsteady flow simulations, with a variable area nozzle downstream simulating an experimental throttle. Computations were performed at 60% of the rotor design speed. Two different degrees of damage for one blade and multiple damaged blades were investigated. Rotating stall characteristics differ including the number of stall cells, propagation speed and rotating stall cell characteristics. Contrary to expectations, damaged blades with typical degrees of damage do not show noticeable effects on the global compressor performance near stall.

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