Swept-Wing Laminar Flow Control Using Sweeping Surface Relief under Enhanced Level of External Disturbances

The effect of quasi-two-dimensional protruding relief elements (strips) inclined to the flow direction on the position of laminar-turbulent transition on a wing model with a sweep angle of 45° is studied using quantitative thermography under various experimental conditions. The robustness of the sweeping surface relief method for laminar flow control in the presence of enhanced freestream turbulence and increased wing surface roughness is investigated and discussed. It is shown that this laminar flow control method is also robust to moderate variations in freestream velocity.