Improvement of effectiveness of EMHD flow separation control
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The present numerical study shows that the effectiveness of flow separation control using Electro-Magneto-Hydro-Dynamic (EMHD) method can be improved by choosing the dimensions of the actuator based on the Reynolds number and the shape of the model studied. The width of the electrode/magnet for most effective flow separation control should be approximately 2.5 times the boundary layer thickness, which in turn is dependent on the Reynolds number. The length of the EMHD actuator for most effective flow separation control can be the shortest based on manufacturing constraints as well as on the possibility of shifting of separation point. The application of Lorentz force inside the boundary layer near the separation point provides the most effective flow separation control. The studies are done for flow over a cylinder in low Reynolds number regime (Reynolds number = 200) and for flow over an elliptical airfoil in high Reynolds number regime (Reynolds number = 1.6 × 105).
KeywordsEMHD actuator Flow separation control Numerical Effectiveness Improvement Boundary layer
The authors would like to thank Indian Institute of Bombay, Powai, India for providing the opportunity to do the associated work.
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