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Showing 1 to 13 of 13 for “"Compressor Stall"”.
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Axial compressor stall.
… the experimental investigation of rotating stall in compressors of high hub-tip ratio. Measurements were obtained in builds of one to four stages, covering a wide range of design flow rates and also a change in design reaction. The purpose of the experimental work has been to gain a better …
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Unsteady disturbance structures in axial flow compressor stall inception
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1994.
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An assessment of body force representations for compressor stall simulation
This thesis examines an axial compressor body force representation constructed from 3D CFD calculations. The radial distribution of body forces is compared to that of a body force representation based on axisymmetric streamline curvature (SLC) calculations, and shown to be in qualitative agreement …
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Axial Compressor Design with Counter-Rotation and Variable RPM for Stall Mitigation
<p>Compressor Stall, an aerodynamic instability due to abnormal air flow in the compressor resulting in loss of total pressure and compressor performance. One of the reasons of compressor stall is due to rise in static back pressure at compressor exit which may result from an imbalance of incidence …
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Inlet flow-field measurements of a transonic compressor rotor prior to and during steam-induced rotating stall
… aircraft's engines upon launch which may induce compressor stall. Investigation of the phenomenon known as a "pop stall" is of particular importance as the Navy prepares to field the F35C, the aircraft carrier variant of the joint strike fighter. The single engine design of the F-35C makes this …
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Role of tip clearance flow on axial compressor stability
… formation of short length-scale (spike) rotating stall disturbances has been carried out. It is found that the onset of growth in tip clearance blockage characterizes the lowest flow coefficient for which a steady blade passage solution exists. It is also found that this condition leads to the …
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A Method to Control Turbofan Engine Starting by Varying Compressor Surge Valve Bleed
… inlet temperature while maintaining an adequate compressor stall margin during engine start by varying the surge valve bleed. Varying the surge valve bleed was also shown to reduce compressor and fan required torque. A new method of turbofan engine component characteristic map extrapolation was …
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Effect of radial transport on compressor tip clearance flow structures and enhancement of stable flow range
… between tip clearance flow structure and axial compressor stall is interrogated via numerical simulations, to determine how casing treatment can result in improved flow range. Both geometry changes and flow field body forces are used as diagnostics to assess the hypothesis that the radial …
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An experimental study of exit flow patterns in a multistage compressor in rotating stall
… of a high-speed, 10- stage, axial-flow compressor operating in rotating stall are analyzed. Procedures used to digitize analog voltages and calibrate pressure transducers are presented. From total and static pressures measured at the exit of the test compressor, stall cell Mach number …
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A Computational Method for Flow Separation Detection and Control for Axial Compressor Airfoils
… full annulus experiments on multistage compressors is costly and time consuming due to the complexity of the experimental processes. To reduce complexity, Computational Fluid Dynamics (CFD) methods are applied to turbomachinery and other applications in recent analysis of such cases. CFD …
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Computational study of the effects of protruding studs casing treatment on the performance of an axial transonic turbofan
Turbo-compressors play a crucial role in the operation of air-breathing engines and special attention is given to the compressor’s ability to withstand adverse operating conditions. Various methods have been devised in order to enhance compressor stability and increase compressor stall margin, …
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Axial compressor stability enhancement
… at all times. One source of instability is compressor stall. Stall problems can be reduced by machining cavities into the compressor casing adjacent to the rotor blades. This ‘casing treatment’ is the focus of the present work. Two treatment configurations are tested: circumferential grooves …
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Unsteady Aerodynamics of Compact Axial Compressors
Compact axial compressors are of interest to the domestic appliance industry. The associated low Reynolds number leads to high losses compared to large-scale compressors due to a transitional flow field with large regions of separation. This thesis investigates how Reynolds number variations affect …