Controlling the aerodynamic drag of a cylinder with gas-permeable porous inserts by regulating base pressure

This Letter presents the results of an experimental and numerical study of a supersonic ($\mathbf{M}_\infty$ = 7) flow past a hollow cylinder with gas-permeable porous inserts, installed along the flow. We demonstrate that it is possible to control the aerodynamic drag of the model by transferring some of the free-stream flow into the base region through gas-permeable porous inserts. The flow rate of the air directed to the base region to control the drag was regulated by heating the porous inserts with an electric glow discharge.