Aerospace Science and Technology
Ali Khoshnejad; Reza Ebrahimi; Golamhosein Pouryossefi
Abstract
Aero-engine entrance conditions are not always ideal and, for various reasons, inlet distortion may occur and cause inlet blockage and reduction of compressor performance. The aim of this study was to numerically simulate the effects of plasma actuators on the enhancement of low-speed axial compressor ...
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Aero-engine entrance conditions are not always ideal and, for various reasons, inlet distortion may occur and cause inlet blockage and reduction of compressor performance. The aim of this study was to numerically simulate the effects of plasma actuators on the enhancement of low-speed axial compressor rotor performance under radial inlet distortion. First, compressor performance under radial inlet distortion with 15% and 20% blockage and theirs destructive effects on stall margin was investigated. Then, the effect of plasma actuators on rotor loss subjected to inlet distortion was investigated, using an algebraic model based on the plasma actuators physics in form of body force distribution in Naiver-Stokes equations. The results show that radial inlet distortion causes decreasing stall margin of the compressor. In addition, according to the findings, applying plasma actuators boosts the flow momentum behind the distortion screen and reduces the blockage of the rotor tip region, leading to decreasing losses. Furthermore, at 15% blockage, the plasma actuators caused to increase the stall margin from -11% to -5% versus the rotor in clean condition.
Aerospace Science and Technology
Majid Sedghi; Rouhollah Khoshkhoo
Abstract
This research aims to numerically investigate the efficiency of the plasma actuator in a small wind turbine. The studies were conducted on a domestic wind turbine with a diameter of 1.93 m and the Suzen-Huang model was employed to simulate the DBD plasma actuator. In this research, first, a wind turbine ...
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This research aims to numerically investigate the efficiency of the plasma actuator in a small wind turbine. The studies were conducted on a domestic wind turbine with a diameter of 1.93 m and the Suzen-Huang model was employed to simulate the DBD plasma actuator. In this research, first, a wind turbine without the plasma actuator was simulated at different tip speed ratios. Then, the DBD plasma actuator was activated at a tip speed ratio of 4.35, and changes in the power output, torque distribution, and surface streamlines were studied. The results indicate with an increase in the power of the plasma actuator, the separation point moved away from the leading edge, the span-wise flows were reduced, and the turbine power output increased. The performance of the plasma actuator is varied along the wind turbine blade length. For the radii r/R=0.4-0.95, a difference in the generated torque can be observed for active and inactive plasma modes, and the plasma actuator did not significantly affect the power output in other sections. The maximum increase in torque due to the plasma actuator has occurred at the radii r/R=0.5-0.7. In these regions, the distance between the separation point and the plasma actuator location is about 0.2 times the chord length of the airfoil.
