Experimental Investigation of the Leading-edge Roughness on the Crossflow Instability of a Swept Wing

An Experimental investigation is conducted to evaluate surface pressure distribution over a semi span swept wing with sweep angle of 33 degrees. The wing section has a laminar flow airfoil similar to that of NACA 6-series airfoils. The tests were conducted at speeds ranging from 50 to 70m/s with and without surface roughness. The differences between pressure distributions on three sections of the wing were are analyzed and the Experimental results showed that addition of surface roughness does not influence the pressure distribution significantly. The spectral analyses were then performed to realize the instability frequencies at each chordwise section