Control jet interaction investigation

Abstract

space applications, stainless steels higher in alloy than type 347 have not been used. Where higher strengths at elevated temperature are required, superalloys have been used, e.g., Inconel-N on the F-l engine. ConclusionsBrazed tube, regeneratively-cooled thrust chambers employing storable liquids (nitrogen tetroxide and Aerozine-50), seldom fail under classical burn-out conditions. Failure mechanisms observed are related to the actual deterioration of stainless steel tubing. Gas-metal reactions (i.e., carburization externally, and carburization and nitriding internally) occur that result in loss of ductility, metal loss on the exterior and interior of the tubes, and, finally, in structural failure (pinholes and cracking) of the weakened and thinned tube.An investigation of the interaction of control jets with the airstream surrounding a typical tactical missile configuration is reported. Rear-mounted bistable fluidic thrusters and circular sonic jets using air, nitrogen, and helium produced jet force ampHfication factors of about 1.6 to 2.2 at Mach numbers 0.9 to 2.0. Amplification factors near unity were measured at Mach 0.6. In general, amplification factors for a finned configuration were higher than for the model without fins. Nomenclature aoo= freestream speed of sound Aj = jet throat area C#,ACjv = normal force coefficient and increment from interaction CN<XO = normal force coefficient slope (dCN/da) at a = 0 D = reference length (body diameter) / -fluid jet switching frequency Fi,Fj = interaction and jet forces K = jet interaction force amplification factor Mj,Moo = jet exit and freestream Mach numbers rap = jet mass flow rate PeyPj = jet exit and jet chamber pressures Poo = freestream static pressure qj,q<» = jet exit and freestream dynamic pressures Vexit = jet exit velocity X cp = center of pressure S = reference area (body cross section) a.-angle of attack 7 = ratio of specific heats

A numerical investigation of supersonic jet interaction for finned bodies

“…The flow field that results from the interaction of a side (lateral) jet injection into a supersonic external flow, called the jet interaction flow field, has been the subject of several experimental [1][2][3][4][5] and numerical [6][7][8][9][10][11] investigations. The typical jet interaction flow field is complicated because the jet interrupts the oncoming external flow.…”