• Advances in aircraft and spacecraft science
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• v.3 no.4
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• pp.367-378
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• 2016

Thrust Vectoring is a dynamic feature that offers many benefits in terms of maneuverability and control effectiveness. Thrust vectoring capabilities make the satisfaction of take-off and landing requirements easier. Moreover, it can be a valuable control effector at low dynamic pressures, where traditional aerodynamic controls are less effective. A numerical investigation of Fluidic Thrust Vectoring (FTV) is completed to evaluate the use of fluidic injection to manipulate flow separation and cause thrust vectoring of the primary jet thrust. The methodology presented is general and can be used to study different techniques of fluidic thrust vectoring like shock-vector control, sonic-plane skewing and counterflow methods. For validation purposes the method will focus on the dual-throat nozzle concept. Internal nozzle performances and thrust vector angles were computed for several range of nozzle pressure ratios and fluidic injection flow rate. The numerical results obtained are compared with the analogues experimental data reported in the scientific literature. The model is integrated using a finite volume discretization of the compressible URANS equations coupled with a Spalart-Allmaras turbulence model. Second order accuracy in space and time is achieved using an ENO scheme.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.483-486
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• 2009

An investigation of the thrust vectoring nozzle which can be applied to the supersonic variable exhaust system was performed. The maximum mach number of the model aircraft is 1.8 and mission radius is about 400Nm. The cycle analysis are performed at each operating regime of the aircraft and the specifications of the thrust vectoring nozzle were developed. Based upon the requirement of the thrust vectoring nozzle, two dimensional thrust vectoring nozzle were designed and flow analysis was conducted by deflection of the pitch and yaw angle.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.192-197
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• 2004

Recently, fluidic thrust vectoring methods have been preferably employed to control the movement of propulsive systems due to relatively simpler design and lower cost than mechanical thrust vectoring methods. For An application of the thrust vectoring to flight bodies, it is necessary to understand very complicated exhaust flows which are often subject to shock waves and boundary layer separation. But researches for the thrust vector control using counterflow have been few. In the present study, experiments have been performed to investigate the characteristics of supersonic jets controlled by a thrust vectoring method using counterflow. The primary jet is expanded through a two-dimensional primary nozzle shrouded by collars, and is deflected by the suction of the air near nozzle into an upper slot placed between the primary nozzle and the upper collar. A shadowgraph method is used to visualize the supersonic jet flowfields. Primary nozzle pressure ratios and suction nozzle pressure ratios are varied from 3.0 to 5.0, and from 0.2 to 1.0 respectively. The present experimental results showed that, for a given primary nozzle pressure ratio, a decrease in the suction nozzle pressure ratio produced an increased thrust vector angle. As the suction nozzle pressure ratios were increased and decreased, the hysteresis of the thrust vectoring was observed through the wall pressure distributions

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.349-352
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• 2008

Thrust vectoring control by injection of secondary jet inside a convergent-divergent supersonic nozzle was studied by both experimentally and computationally. For various stagnation pressure of the secondary jet injected at a specific location(12 mm-downstream of throat) in the divergent section of nozzle, the characteristics of thrust vectoring were observed. Present numerical results were compared with previous investigators' results and Schlieren flow visualizations for the identical boundary conditions, and it showed a qualitatively good agreement. It was also noticed that the characteristics of thrust vectoring is strongly related to the reflection structure of oblique shock inside nozzle, ie., the pressure ratio of the secondary jet, SPR.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.592-597
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• 2003

Thrust vector control using a coflow-counterflow concept is achieved by suction and blowing through a slot adjacent to a primary jet which is shrouded by a suction collar. In the present study, the flow characteristics of thrust vectoring is investigated using a numerical method. The nozzle has a design Mach number of 2.0, and the operation pressure ratio is varied to obtain various flow features of the nozzle flow. Test conditions are in the range of the nozzle pressure ratio from 6.0 to 10.0, and a suction pressure from 90kPa to 35kPa. Two-dimensional, compressible Navier-Stokes computations are conducted with RNG ${\kappa}-{\varepsilon}$ turbulence model. The computational results provide an understanding of the detailed physics of the thrust vectoring process. It is found that an increase in the nozzle pressure ratio leads to increased thrust efficiency but reduces the thrust vector angle.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.5
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• pp.27-34
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• 2011

A numerical analysis was peformed for the supersonic aircraft with variable pitch thrust vector nozzle. Based on the requirement of the mixed turbofan engine of the supersonic aircraft, two dimensional thrust vector nozzle with variable pitch angle was designed. To investigate the effect of the thrust vectoring nozzle, the numerical analysis was conducted by using Fluent under the several pitch deflection angle.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.170-176
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• 2010

A numerical analysis was peformed for the supersonic aircraft with variable pitch thrust vector nozzle. Based on the requirement of the mixed turbofan engine of the supersonic aircraft, two dimensional thrust vector nozzle with variable pitch angle was designed. To investigate the effect of the thrust vectoring nozzle, the numerical analysis was conducted by using Fluent under the several pitch deflection angle.

• Journal of the Korean Society of Visualization
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• v.9 no.3
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• pp.30-37
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• 2011

The thrust vectoring concept has been used for use in new advanced supersonic aircraft. This study presents the performance characteristics of the thrust vectoring nozzle by visualizing the shock behaviors with Schlieren method. The scaled models were designed and manufactured to see the shock behaviors of the various airflow condition. Also we executed experimental tests to see the geometrical effects of the thrust vector nozzle by changing pitch angle and length of pitch flaps. From this study we could understand the supersonic flow characteristics of the thrust vector nozzle. The total thrust of thrust vector nozzle is diminished by increasing the flap angle. But there is an optimum flap length ratio for attaining the highest thrust level and proper pitch effect.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.9
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• pp.723-730
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• 2014

Experimental study for supersonic co-flowing fluidic thrust vectoring control utilizing the secondary flow is performed. The characteristics of the thrust vectoring of two dimensional supersonic flow (Mach 2.0) are studied by Schlieren flow visualization and highly-accurate multi-component force measurements using the load cells. It is observed that the thrust deflection angle initially decreases and increases again forming a V-shaped variation as the pressure of the secondary flow increases. Characteristics of the performance coefficients of the system are also studied, and the detailed operating conditions for higher performance of the technique are suggested.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.7
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• pp.658-668
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• 2004

This paper is concerned with a control allocation strategy using the dynamic inversion and the pseudo inverse control which generates the nominal control input trajectories. In addition, an autopilot design method is proposed by using time-varying control technique which is time-varying version of the pole placement of linear time-invariant system for an agile missile with aerodynamic fin and thrust vectoring control. The control allocation proposed in this paper is capable of extracting the maximum performance by combining each control effector, aerodynamic fin and thrust vectoring control. The adopted time-varying control technique for the autopilot design enhances the robustness of the tracking performance for a reference command. The main results are validated through the nonlinear simulations with aerodynamic data.