Secondary Injectant Gas Thermodynamic Properties Effects on Fluidic Thrust Vectoring Performances of a Supersonic Nozzle

International audienc

Secondary Injectant Gas Thermodynamic Properties Effects on Fluidic Thrust Vectoring Performances of a Supersonic Nozzle

International audienceThe transverse injection in a supersonic cross-flow is problematic which can be encountered in several aerodynamic applications such as fuel injection in scramjet combustor, missile control, drag reduction, and thrust vector control. In recent years, an extended analytical, numerical, and experimental work has been carried out by the authors to investigate the vectoring performances of a supersonic axisymmetric nozzle using secondary fluid injection. Secondary gas injection thrust vector control (SITVC) orshock vector control (SVC) is considered as an alternative way to control the thrust direction of a rocket nozzle beside the classical use of mechanical device such as fluidic actuators. In the context of SITVC operation, the nature and source of injectant gas may raise efficiency-related issues. In previous studies, it is well established that injection of gas with low molar mass promotes better jet penetration and therefore will be a better choice for SITVCoperation. To assess this point, an experimental test campaign has been conducted in the hypersonic test facility EDITH of the CNRS institute ICARE in Orléans, France.The focus of the study is to analyze the secondary injectantgas thermodynamic properties influence on the global vec-toring performance of a supersonic nozzle. For this purpose,performance aspects of fluidic thrust vectoring concept have been experimentally investigated on a truncated ideal contour (TIC) nozzle model using a variety of gas species(with low to moderate molar mass) as injectant. Qualitativeand quantitative diagnostics consisted of Z-Schlieren visualization, 3-axis force balance, and static and dynamic parietal pressure measurements. The experimental results are compared to the numerical and analytical findings

Thrust vectoring effects of a transverse gas injection into a supersonic cross-flow of an axisymmetric C-D nozzle

International audienc

Experimental–Numerical Parametric Investigation of a Rocket Nozzle Secondary Injection Thrust Vectoring

International audienceSecondary transverse injection into the divergent section of an axisymmetric convergent–divergent propulsive nozzle is investigated for the fluidic thrust vectoring effects. Coupled experimental and numerical cold-flow investigation on the number of cases and aspects was conducted in the framework of a French microsatellite launcher program. Five experimental test nozzles were designed, built, and equipped with diagnostic tools. All experimental test models were supported by full three-dimensional numerical simulations and further investigated using the additional nozzle models, cases, and analysis parameters. Pertinent side force and pitch vector angle of 5–9 deg were achieved within the 5–8% range of the secondary to primary mass-flow-rate ratio. Investigation aspects, categorized as the nozzle vectoring system geometrical characteristics, primary and secondary flow conditions, and gas intrinsic properties were found to dominantly affect the thrust vectoring capabilities. Some further improvements are suggested and achieved in the optimization of selected parameters

Experimental and Numerical Study of Thrust-Vectoring Effects by Transverse Gas Injection into a Propulsive Axisymmetric C-D Nozzle

International audienc