Parametric scaling and flow categories characterization in minijet-manipulated supersonic jets for shock vector control

A parametric study is numerically conducted for the Shock Vectoring Control (SVC) of a round supersonic jet with a design Mach number 1.5 using a single steady minijet. Control performance is quantified by the thrust vectoring angle. Three control parameters are extensively investigated, including the mass flow rate ratio, injection location of the minijet, and nozzle pressure ratio of the main jet. Numerical simulations point out that the thrust vectoring angle depends on these three control parameters. Careful scaling analysis unveils that the three parameters may be reduced to a single dimensionless scaling factor, quantifying the vectoring angle. The scaling factor is physically the penetration depth of the minijet into the main jet. A detailed discussion is conducted based on this scaling law on the prediction of optimal efficiency for practical applications, which is a new indicator of merit to evaluate the performance of SVC systems. Intriguingly, the SVC of jet is further classified into four typical flow categories, for which corresponding physical conceptual models are also proposed.