Experimental/Numerical Investigation of the Influence of a Pressure Gradient on Acoustic Roughness Receptivity in the Boundary Layer of a 2-D Airfoil
نویسندگان
چکیده
In the present paper, the influence of a pressure gradient on the acoustic roughness receptivity is investigated by means of wind tunnel experiments and Direct Numerical Simulations (DNS). The receptivity function for three different locations of a 3-D surface non-uniformity on a 2-D airfoil is calculated from the experimental and numerical data and compared to each other. The combined effects of the roughness acoustic receptivity and the amplification of the generated disturbances are taken into account in order to evaluate the position on the airfoil at which a surface non-uniformity is most dangerous in provoking an early transition.
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