Numerical Investigations Of A Transverse Jet Interaction With Supersonic Free Stream

Transverse jet control technology use the jet thrust to control the flight attitude. Ithas the advantages of fast response and high efficiency compared to conventionalpneumatic rudder in the spacecraft attitude control. When the supersonic jet injectedinto a supersonic stream, jet generate complex interference phenomenon, Interferenceflow field for aircraft generate additional aerodynamic force and pneumatic moment,which is adverse to precise attitude control. Accurate prediction of the interference flowfield and the influence of the aerodynamic characteristics of aircraft can improve thespraying flow control efficiency and ensure the stability of the flight.Lateral jet interference on a vehicle in supersonic free stream is numericallystudied by solving the asymmetric and three dimensional Navier-Stokes equationscoupled with standard k-turbulence model. Select flow field and aerodynamiccharacteristics of lateral jet at zero angle of attack for example to verification algorithmhas high reliability and accuracy to deal with the transverse jet interaction withsupersonic free stream. Based on this, further study is made on lateral jet flow structureand its impact on the aerodynamic characteristics of the aircraft varied flight angle ofattack, jet pressure ratio and nozzle position.It has been observed that lateral jet interferences and gas dynamic gainperformance varies linearly with small attack angle. A peak value of force amplificationfactor and moment amplification factor appeared with the increase of angle of attack. Itis also found that the jet interaction has greater influence on gas dynamic gainperformance when the jet exit is in the windward side, so it is to the jet interferenceswhen the jet exit is in the leeward side. With the increase in the pressure ratio of the jet,the jet flow field generated interference range increases, jet parcels enhanced role jetpenetration ability. And the force amplification factor and moment amplification factordecreases, that is to say the larger the jet pressure ratio, the smaller flow field andaircraft lateral force and pitching moment of impact are. With the increase of the jetposition distance, the force amplification coefficient increases, the momentamplification factor reduced. That means flow field aircraft larger lateral force, whilethe smaller interference additional torque of the flow field generated by the aircraft.Interference range of flow field increases as altitude increases, but reducing theinfluence of the aerodynamic characteristics of the aircraft.