Shock wave is a detriment in the development of supersonic aircrafts; it increasesflow drag as well as surface heating from additional friction; it also initiates sonicboom on the ground which precludes supersonic jetliner to fly overland. A shockwave mitigation technique is demonstrated by experiments conducted in a Mach 2.5wind tunnel. Non-thermal air plasma generated symmetrically in front of a windtunnel model and upstream of the shock, by on-board 60 Hz periodic electric arcdischarge, works as a plasma deflector, it deflects incoming flow to transform theshock from a well-defined attached shock into a highly curved shock structure. In asequence with increasing discharge intensity, the transformed curve shock increasesshock angle and moves upstream to become detached with increasing standoff distancefrom the model. It becomes diffusive and disappears near the peak of the discharge.The flow deflection increases the equivalent cone angle of the model, whichin essence, reduces the equivalent Mach number of the incoming flow, manifestingthe reduction of the shock wave drag on the cone. When this equivalent cone angleexceeds a critical angle, the shock becomes detached and fades away. This shockwave mitigation technique helps drag reduction as well as eliminates sonic boom.
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