... urbomachinery . 07 07 2022 13 01 2023 13 01 2023 10 02 2023 cavity and leaking flows computational fluid dynamics (CFD) high pressure turbine winglets squealers flow control In unshrouded axial flow high-pressure turbines, tip clearance is provided between the blade...

...Hunter D. Nowak; Federico Lluesma-Rodriguez; Iman Rahbari; John P. Clark; Guillermo Paniagua A new class of power generation devices that experiences increased losses due to bulk flow separation in segments of their expected in-flight regime is emerging. As such, active flow control becomes...

.... The optimal shape, moreover, still holds similar level of superior performance at off-design conditions. The result may suggest a possible paradigm shift in flow control concept, away from disruptive penalty ridden devices, by properly conditioning and guiding the flow. The N + 2 configuration...

...Jeffrey P. Bons; Jon Pluim; Kyle Gompertz; Matthew Bloxham; John P. Clark The synchronous application of flow control in the presence of unsteady wakes was studied on a highly loaded low pressure turbine blade. At low Reynolds numbers, the blade exhibits a nonreattaching separation bubble under...

... performance in an environment with leakage flows and associated cavities. 26 11 2008 04 12 2008 14 07 2011 14 07 2011 blades design engineering flow control turbines The implementation of blade lean and other three-dimensional geometrical features to control the flow...

... compressors flow control rotors Compressor blade-tip leakage flow is a large source of loss and affects the stable operating envelope of the axial compressor ( 1 2 3 4 5 ). In many cases, these detrimental effects are magnified at large tip clearance levels. The present trend in aircraft engine...

...Arne Vorreiter; Susanne Fischer; Horst Saathoff; Rolf Radespiel; Joerg R. Seume Airfoil active flow control has been attempted in the past in order to increase the permissible loading of boundary layers in gas turbine components. The present paper presents a stator with active flow control...

...Daniel Nerger; Horst Saathoff; Rolf Radespiel; Volker Gümmer; Carsten Clemen The following paper describes an experimental investigation of a highly loaded stator cascade with a pitch to chord ratio of t / l = 0.6 . Experiments without as well as with active flow control by means of endwall...

... velocity from the cascade) of 25,000 and 50,000. Jet pulsing frequency, duty cycle, and blowing ratio were all varied. Computational results from a large eddy simulation of one case showed reattachment in agreement with the experiment. In cases without flow control, the boundary layer separated and did...

... separation point and the synthetic jet is just at the separation point. actuators compressors flow control flow instability flow separation jets Navier-Stokes equations In the modern aero-engine design, the tendency toward weight reduction and pressure ratio enhancement leads to stronger...

.... Plasma actuators are a new and simple type of active flow control device consisting of two parallel and offset electrodes separated by a layer of dielectric material. The application of a high ac voltage at high frequency to the electrodes generates a body force on the flow in the vicinity...

.... Corsini , A. , and Sheard , A. G. , 2007 , “ Tip End-Plate Concept Based on Leakage Vortex Rotation Number Control ,” Comput. Appl. Math. 0101-8205 , 8 ( 1 ), pp. 21 – 37 . 06 08 2008 25 02 2009 24 03 2010 24 03 2010 fans flow control interference...

... can be especially damaging. Studies have shown that flow control by trailing edge blowing (TEB) can reduce stator wake strength and the amplitude of the downstream rotor blade vibrations generated by the unsteady stator-rotor interaction. In the present study, the effectiveness of TEB to reduce forced...

... between VGJ actuation and the wake passing was optimized. Both steady state C p and phase-locked velocity measurements confirm that the optimal combination of wakes and jets yields the smallest separation. 14 08 2007 29 08 2007 03 02 2009 blades flow control flow instability flow...

... that the device is able to control partially all the critical flows with no penalty for the efficiency. Finally, some recommendations for the design of passive treatments are presented. 18 12 2007 19 05 2008 29 01 2009 blades boundary layers compressors flow control flow separation...

... to develop promising strategies for reducing the influence of shroud leakage flow. The experimental program of this study was conducted on a three-stage model air turbine, which was extensively supported by CFD analysis. Three different concepts for shroud leakage flow control in the exit cavity were...

... flow control actions to mitigate hub-corner stall. As an illustration, a flow control blade, designed using the ideas developed, is seen to produce a substantial reduction in the flow nonuniformity associated with hub-corner stall. 28 07 2006 12 02 2007 02 05 2008 blades...

...Xinqian Zheng; Sheng Zhou; Yajun Lu; Anping Hou; Qiushi Li An experimental investigation conducted in a stationary annular cascade wind tunnel demonstrated that unsteady flow control using synthetic jets (zero mass flux) could effectively reduce flow separation in the axial compressor cascade...

... turbines is dominated by the leakage flow and that reduction in the leakage flow reduces the intensity of the secondary flow and its radial migration toward the midspan in the downstream blade row. In order to evaluate the quality of the shroud leakage flow control strategy presented in this paper...

... bubble (50% c x ). Measurements provide a comprehensive picture of the interaction of boundary layer transition and separation in this unsteady environment. Similarities between pulsed flow control and unsteady wake motion are highlighted. VGJ exit velocity profile (inset of jet configuration...