Results 271 to 280 of about 160,183 (291)

Rotordynamic effects of compressor rotor-tip clearance asymmetry

AIAA Journal, 2001
Rotordynamic effects caused by nonaxisymmetric rotor-tip clearance in an axial compressor stage have been analyzed. Two coupled actuator discanalyses are carried out at blade (meridional plane )andradius(radial plane ) scales. Continuity, axial, and tangential momentum equations are used to connect upstream and downstream e ows across the compressor ...
Seung Jin Song, Kil Yong Park
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Turbine Tip-Clearance Measurement.

1977
Abstract : This report describes the analysis and measurement of turbine tip clearance over the full range of operation of an advanced gas turbine engine. The first-stage turbine of the Lycoming advanced gas generator was used as the test vehicle for analytic and experimental evaluation. Tip-clearance response of the stage was analyzed for steady-state
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Study on Effect of Rotor Vibration on Tip Clearance Variation and Fast Active Control of Tip Clearance

Advanced Materials Research, 2010
The tip clearance flow of axial turbomachines is important for their aerodynamic and maneuver performance. And the tip clearance gap leakage flow is of continuing concern in reducing efficiency losses that occur within turbines. In order to gain significant reductions in emissions and specific fuel consumption as well as dramatic improvements in ...
Bing Hui Jia, Xiao Dong Zhang
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Effects of Rotor Tip Clearance on Tip Clearance Flow Potentially Leading to NSV in an Axial Compressor

Volume 7: Structures and Dynamics, Parts A and B, 2012
This paper investigates non-synchronous vibration (NSV) mechanism of a high-speed axial compressor with three different rotor tip clearances. Numerical simulations for 1/7th annulus periodic sector are performed using an unsteady Reynolds-averaged Navier-Stokes(URANS) solver with a fully conservative sliding boundary condition to capture wake ...
Hong-Sik Im, Ge-Cheng Zha
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A Microwave Blade Tip Clearance Sensor for Active Clearance Control Applications

40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 2004
Active clearance control has been used to improve efficiency and performance in commercial aircraft engines. Technologies implemented to date rely on compressor bleed air to control clearances based on open loop control and the flight regime (takeoff, cruise, etc.).
Jonathan Geisheimer, Scott Billington, David Burgess   +2 more
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Tip Clearance Signal Processor Development

1988
Abstract : A signal processing system was designed and constructed to detect peaks of the Vatell eddy current clearance sensor signal, measure their amplitude and timing, and compute a correction for machine speed to indicate clearance and time arrival for individual blades of a turbomachine.
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Tip Clearance and Tip Vortex Cavitation in an Axial Flow Pump

Journal of Fluids Engineering, 1997
A combined study of tip clearance and tip vortex cavitations in a pump-type rotating machine is presented. Cavitation patterns are observed and cavitation inception is determined for various gap heights, clearance and blade geometries, and rotor operating conditions.
R. Laborde, P. Chantrel, M. Mory
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The Tip Leakage Vortex Shed from an Unsteady Tip Clearance Flow

34th AIAA Fluid Dynamics Conference and Exhibit, 2004
*† ‡ , The interaction between the rotor blade tip leakage flow and inflow disturbances, such as encountered in shrouded marine propulsors, was simulated in the Virginia Tech Linear Cascade Wind Tunnel equipped with a moving endwall system. The idealized periodic inflow unsteadiness was generated using vortex generator pairs upstream of the blade row ...
Nanyaporn Intaratep, William Devenport, Josh Staubs   +2 more
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Propeller tip clearance and afterbody form

International Shipbuilding Progress, 1969
This report presents some simple theoretical considerations of how the transverse slope of the sections of the stern above the propeller is expected to influence the propeller-induced vibratory surface force in vertical direction on the afterbody. The results indicate that flat-bottomed sections are preferable.
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Unsteady Effects in Turbine Tip Clearance Flows

Journal of Turbomachinery, 2000
The present study is concerned with the unsteady flow field on the blade outer air seal segments of high-work turbines; these segments are installed between the blade tip and outer casing and are usually subjected to extreme heat loads. Time-resolved measurements of the unsteady pressure on the blade outer air seal are made in a low-speed turbine rig ...
Anil Prasad, Joel H. Wagner
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