Numerical research of gaseous fuel preinjection in hypersonic three-dimensional inlet

Numerical results of gaseous ethylene and propane fuel preinjection in a hy personic three-dimensional inlet and the attendant fuel-air mixing enhancem ent process are analyzed. Fuel is injected in the wake of thin swept pylons located on the inlet's compression surface (installed normal to the wall), 1-2 injector diameters downstream of the pylons. Mixing in the near vicini ty of the pylons is calculated using the Favre-averaged Navier-Stokes equat ions for three-dimensional, turbulent, multispecie, nonreacting flows, taki ng into account all of the jets. Calculations of the flowfield in the far m ixing region of the inlet channel are based on solutions of the parabolized Navier-Stokes equations. It is shown that fuel-air mixing efficiencies bet ween 0.95 and 0.98 are possible for fuel-air equivalence ratios between 0.3 and 0.7 before exiting an inlet channel whose length is 0.65 m.