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Delay Of Rotating Stall In Compressors Using Plasma Actuation
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Book Synopsis Delay of Rotating Stall in Compressors Using Plasma Actuation by : Farzad Ashrafi
Download or read book Delay of Rotating Stall in Compressors Using Plasma Actuation written by Farzad Ashrafi and published by . This book was released on 2014 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rotating stall is a well-known aerodynamic instability in compressors that limits the operating envelope of aircraft gas turbine engines. An innovative method for suppressing the most common form of rotating stall inception using an annular DBD plasma actuator had been proposed. A DBD plasma actuator is a simple solid-state device that converts electricity directly into flow acceleration through partial air ionization. However, the proposed concept had only been preliminarily evaluated with simple numerical simulations on an isolated axial rotor using a relatively basic CFD code. The current project provides both an experimental and a numerical assessment of this concept for an axial compressor stage as well as centrifugal compressor stage that are both part of a low-speed two-stage axial-centrifugal compressor test rig. The two configuration studied are the two-stage configuration with a 100 mN/m annular casing plasma actuator placed just upstream of the axial rotor leading edge, and the single-stage centrifugal compressor with the same actuator placed upstream of the impeller leading edge. The tested configuration were simulated with a sophisticated commercial RANS CFD code (ANSYS CFX) in which was implemented the latest engineering DBD plasma model and dynamic throttle boundary condition, using single-passage multiple blade row computational domains. The experiments show that the casing plasma actuator reduces the mass flow of the last stable point (stall point) by 19.28% for the axial compressor stage and 28.39% for the centrifugal compressor stage for which the impeller is the source of rotating stall. The CFD simulations indicate that in both types of compressors the actuator delays the stall inception by pushing the incoming/tip clearance flow interface downstream into the blade passage. In each case, the predicted percentage reduction in stalling mass flow matches the experimental value reasonably well. However, the CFD simulations over-predicts the mass flow of the stall point as well as the pressure rise of the centrifugal stage and under-predict the pressure rise of the axial stage. The main factors for the difference are likely slight discrepancies between the simulated and actual axial rotor blade geometry deformation and the inability of the simulation tool to accurately capture the total pressure loss in the hub region of the vaneless diffuser.
Book Synopsis Delaying the Onset of Rotating Stall in an Axial Compressor by : Seth Thomas
Download or read book Delaying the Onset of Rotating Stall in an Axial Compressor written by Seth Thomas and published by . This book was released on 2011 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Actuation for Rotating Stall Control of High Speed Axial Compressors by : Roland Günter Berndt
Download or read book Actuation for Rotating Stall Control of High Speed Axial Compressors written by Roland Günter Berndt and published by . This book was released on 1995 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Analytical and Experimental Investigation of Rotating Stall Phenomena in Turbine Engine Compressors by :
Download or read book Analytical and Experimental Investigation of Rotating Stall Phenomena in Turbine Engine Compressors written by and published by . This book was released on 1967 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Active Control of Rotating Stall in a Three-stage Axial Compressor with Jet Actuators by : Huu Duc Vo
Download or read book Active Control of Rotating Stall in a Three-stage Axial Compressor with Jet Actuators written by Huu Duc Vo and published by . This book was released on 1997 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Compressor Surge and Stall by : R. C. Pampreen
Download or read book Compressor Surge and Stall written by R. C. Pampreen and published by . This book was released on 1993 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt: High efficiency axial and centrifugal compressors are important in fields as diverse as aircraft engines, superchargers and turbochargers, process and refrigeration compressors. Compressors must achieve high efficiency in blade rows in diffusing flow fields. Of equal and sometimes greater importance is the range os stable operation of the compressor. Blade row stall characteristics determine the limit os stable operation. Blading can stall uniformly with symmetric flow breakdown or asymmetrically in rotating stall, wich propagates around the periphery of the blade row. Depending on aerodynamic conditions, surge may occur instead of, in concert with, or subsequent to blade row stall. The transient breakdown and recovery of aerodynamic loading not only limits compressor performance but also leads to mechanical failures caused by the vibrational loads imposed on the blades. There is no need to know what initiates these performance limits so that surge and stall margins can be optimized and control strategies can be planned. the first step toward understanding is to be knowledgeable about he physical processes occurring during surge and stall. This will permit the designer to anticipate variable geometry needs such as variable inlet guide vanes, variable statuors, and bleed port strategies. Theoritical treatment is far from being well established, however, there are many approaches discussed in the literature. This book is a unique reference to the subject matter. Physical descriptions of the phenomena are given, test results are presented, and analytical studies are discussed. There has been much written about the experimental investigations and theoretical treatments related to surge and stall. To assist those who would pursue advancements in furthering ou knowledge of surge and stall, it seemed appropriate to have a resource that contains a compendium of information on this subject. That is the purpose of this book. [Source : d'après la 4e de couverture].
Book Synopsis Research on Rotating Stall in Axial Flow Compressors by : F. K. Moore
Download or read book Research on Rotating Stall in Axial Flow Compressors written by F. K. Moore and published by . This book was released on 1959 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Active Stabilization of Rotating Stall and Surge in a Transonic Single Stage Axial Compressor by : Harald Jürgen Weigl
Download or read book Active Stabilization of Rotating Stall and Surge in a Transonic Single Stage Axial Compressor written by Harald Jürgen Weigl and published by . This book was released on 1997 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Scientific and Technical Aerospace Reports by :
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Active Control of Rotating Stall in Axial Compressors by : James Donald Paduano
Download or read book Active Control of Rotating Stall in Axial Compressors written by James Donald Paduano and published by . This book was released on 1992 with total page 319 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Active Control of Compressor Rotating Stall Using Linear Amplitude Feedback by : Nikos Markopoulos
Download or read book Active Control of Compressor Rotating Stall Using Linear Amplitude Feedback written by Nikos Markopoulos and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Effect of Compressor Parameters on Rotating Stall by : Saju Thomas Joseph
Download or read book Effect of Compressor Parameters on Rotating Stall written by Saju Thomas Joseph and published by . This book was released on 1985 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Research on Rotating Stall in Axial Flow Compressors by : R. A. Hartunian
Download or read book Research on Rotating Stall in Axial Flow Compressors written by R. A. Hartunian and published by . This book was released on 1959 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author :National Aeronautics and Space Administration (NASA) Publisher :Createspace Independent Publishing Platform ISBN 13 :9781726206143 Total Pages :28 pages Book Rating :4.2/5 (61 download)
Book Synopsis An Investigation of Surge in a High-speed Centrifugal Compressor Using Digital Piv by : National Aeronautics and Space Administration (NASA)
Download or read book An Investigation of Surge in a High-speed Centrifugal Compressor Using Digital Piv written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-27 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 successfully control these events. 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 simultaneously capture transient velocity and pressure measurements in the non-stationary flow field during compressor surge. DPIV is an instantaneous, planar measurement technique which is ideally suited for studying transient flow phenomena in high speed turbomachinery and has been used previously to successfully 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.Wernet, Mark P. and Bright, Michelle M. and Skoch, Gary J.Glenn Research CenterCENTRIFUGAL COMPRESSORS; ROTATING STALLS; PARTICLE IMAGE VELOCIMETRY; PRESSURE MEASUREMENT; DYNAMIC PRESSURE; PRESSURE SENSORS; TRANSIENT PRESSURES; UNSTEADY FLOW...
Book Synopsis Analytical and Experimental Investigation of Rotating Stall Phenomena in Turbine Engine Compressors by : W. Gordon Brady
Download or read book Analytical and Experimental Investigation of Rotating Stall Phenomena in Turbine Engine Compressors written by W. Gordon Brady and published by . This book was released on 1967 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: A research program to investigate fundamental mechanisms of rotating stall in axial-flow turbojet engine compressors is described. Analysis of the lift hysteresis of an oscillating elliptic airfoil at stall indicates that including the effects of a moving separation point on the criterion for separation of the boundary layer has a negligible effect on the computed lift hysteresis. Attempts were made to modify a previously developed rotating small-disturbance stability theory based on an actuator representation of blade rows so as to improve theoretical predictions of rotating stall. These attempts included modifications of blade-row representation, inclusion of viscous dissipation effects in the flow away from blade rows, and extension of the stability theory to include three-dimensional unsteady flows. The only modification of the stability theory which appeared to improve theoretical prediction of flow instability and for which numerical results were obtained was the assumption of actuators of finite thickness incorporated in the analysis of a configuration with a rotor plus a row of upstream guide vanes. It is concluded that more research is required before a final assessment of the validity of the rotating small-disturbance stability theory can be made. An annular cascade was designed and fabricated. The preliminary rotating-stall data obtained from the cascade are presented and discussed.
Book Synopsis Research on Rotating Stall in Axial Flow Compressors by :
Download or read book Research on Rotating Stall in Axial Flow Compressors written by and published by . This book was released on 1959 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Control of Compressor Rotating Stall Without Distributed Sensing Using Bifurcation Stabilization by :
Download or read book Control of Compressor Rotating Stall Without Distributed Sensing Using Bifurcation Stabilization written by and published by . This book was released on 1996 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Control of rotating stall in axial compressors is considered. A local bifurcation stabilization theorem using the projection method for the case of an uncontrollable, unobservable critical mode is described and extended to control laws that do not vanish at the critical or bifurcation point. This result is used to derive sufficient conditions for several control laws to guarantee that the subcritical pitchfork bifurcation of an axial compressor model is made supercritical so that the rotating stall hysteresis is eliminated. Each of the control laws considers operation at a set point distinct from the critical point and depends only on annulus-averaged quantities as feedback variables to simplify sensing and signal processing requirements. The actuation considered is a bleed valve so that the control law must be positive for all possible values of the feedback variables. It is shown that positive control is stabilizing for only some of the control laws considered. In these cases, numerical examples show the transformation of the bifurcation from subcritical to supercritical and the elimination of the hysteresis region. Finally, geometric interpretations of the effects of the feedback laws in the state space are described.
