CONTROL OF SUBSONIC FLOW AROUND A SEMICIRCULAR AIRFOIL WITH THE USE OF SLOT SUCTION IN VORTEX CELLS

With the use of multiblock computational technologies and the shear stress transport model modified with regard
for the curvature of streamlines, calculations of the nonstationary turbulent flow of an incompressible fluid around
a semicircular airflow, on the contour of which one or two circular vortex cells with slot suction are placed, at a
zero angle of attack have been performed. On the basis of the calculation data obtained, regimes of stabilizing the
flow around such an airfoil, close to the flow without separation, and the possibility of achievement of the extremal
lift coefficient C _y = 5.8 by it at a lift-drag ratio K = 10, determined with account of the energy expended for the
suction in the vortex cells, have been revealed. It was established that when the Mach number of the undisturbed
flow around a semicircular airflow with two vortex cells increases to the critical value, C _y and K of the airfoil
increase. In this case, C _ymax and K _max are of the order of 6.2 and 14.5, respectively. In the case of flow around this
airfoil at a Mach number larger than M _cr, the second vortex cell does not function, and the flow around the airfoil
becomes detached

Author:  S. A. Isaev, D.V. Nikushchenko, A. G. Sudakov, L. P. Yunakov, N. V. Tryaskin
Keywords:  semicircular airfoil, vortex cell, slot suction, turbulence, calculation
Page:  1278