The supersonic–supersonic ejector–diffuser system is employed to suck supersonic low-pressure and low-temperature flow into a high-pressure environment. A new design of was introduced verify pressure control performance under different operating conditions vacuum background pressure. 1D analysis used predict the geometrical structure an with rectangular section based on given conditions. Different numbers types nozzle plates were designed installed ejector study realizability avoiding or...

A promising strategy of synthetic jet arrays (SJA) control for NACA0021 airfoil in preventing flow separation and delaying stall is investigated. Through aerodynamic forces, flowfield velocity profiles measurements, it indicates that the (SJ) could enlarge mixing shear layer then enhance stability boundary layer, resulting scope reduction zone. Furthermore, effects dual positioned at 15%c (Actuator 1) 40%c 2) respectively are systematically investigated with different parameters, such as two...

We investigated the mechanism of hysteresis and uncontrolled deflection in jet vectoring control based on Coanda effect. Thrust effect is highly applicable field fluid dynamics because they can achieve with a simple geometric structure low energy consumption. However, phenomena considerably hinder practical application these technologies. designed new passive fluidic thrust model to analyze disadvantages. developed synchronous pressure, force, flow measurement system investigate evolutions...

The wind tunnel experiments was conducted to get inspiration for understanding the mechanism of asymmetric flow pattern and developing an innovative control technique a slender body at high angle attack. bi-stable situation side forces observed which could be easily switched by tiny disturbances either from coming or artificial nose tip (including manufacturing defect). In turbulent flows randomly between positive negative. There existed hysteresis loop force with rolling angle. A rod in...

Aiming at the problem of continuous control asymmetric forebody vortices a high angle attack in bi-stable regime, dual synthetic jet actuator embedded an ogive was designed. Alternating unsteady disturbance with varying degree asymmetrical flow fields near nozzles is generated by adjusting duty cycle drive signal actuator, specifically embodying time-averaged pattern velocity, vorticity, and turbulent kinetic energy. Experimental results show that within range relatively angles attack,...

In view of the control effects fluidic thrust vector technology for low-speed aircraft at high altitude/low density and low altitude/high are studied. The S-A model FLUENT software is used to simulate flow field inside outside nozzle with variable surface parameters, relationship between area deflection effect main different altitudes obtained. It found that vectoring can effectively internal in ground state state. mainstream angle be continuously adjusted. maximum 21.86°, deviation 20 km...

The wind tunnel experiments is conducted to get inspiration for understanding the mechanism of asymmetric flow pattern and developing an innovative control technique a slender body at high angle attack. bi-stable situation side forces observed, which could be easily switched by tiny disturbances either from coming or artificial nose tip (including manufacturing defect). In turbulent flows randomly between positive negative. There exists hysteresis loop force with rolling angle. A rod in...

The low-frequency pressure pulsations in a large low-speed open jet wind tunnel were studied using 1:20 scaled model tunnel. It was found that plane standing waves existed all three directions of the tunnel’s plenum. confirmed transverse direction plenum caused by resonance with edgetone feedback (vortex-sound between nozzle and collector). analysis vertical suggested they might come from self-excited oscillations. For strictly collector, much stronger than those other two directions. By...

A miniature air data system based on a seven-hole probe was developed for real-time, in-flight measurement of wind flow deviation angle and inertial parameters. The is very small in size weighs only 150 g, especially suitable flight tests with unmanned aerial vehicles (UAVs). It capable measuring attack (AOA) sideslip (AOS), ranging up to ±78°. exposed part slender fixed the nose aircraft, which 4 mm diameter. spin test conducted delta-wing, body aircraft; experimental results demonstrate...

To provide sufficient lift during takeoff and landing, large aircraft are equipped with complicated high-lift devices. The use of simple flaps coupled active flow control (AFC) can achieve improvement while reducing mechanical structure weight. present study focuses on verifying the feasibility effectiveness combined sweeping jet control. An experimental AFC flaps, using jets, was carried out a NASA SC(2)-0410 supercritical airfoil wind-tunnel model at Re = 2.0 × 105 (with velocity V 10...

The fluid thrust vectoring nozzle has a fixed profile, few moving parts, and lightweight structure, providing effective flight control for high maneuvering aircraft. nonlinear law of the jet deflection angle is one critical problems vector technology. However, research on thermal in not ideal. In this paper, micro-turbojet engines under studied by numerical simulations experiments. results show that caused vortex structure between main wall. passive flow method can effectively change...

The wind tunnel experiments for high angle of attack aerodynamics were designed from the inspiration understanding mechanism and development an innovative flow control technique. side force, varying with different rolling angle, is featured by bi-stable situation, can be easily switched a tiny disturbance. A miniature strake attached to nose tip model. When stationary, direction force controlled. strake, as unsteady means, swung pattern could results obtained dynamic measurements section...

The lateral hysteretic characteristic generated by asymmetric vortical flow behind the tangent-ogive cylinder is investigated without and with micro synthetic jet control, when slender body undergoes a large amplitude pitching motion. Experiments are conducted in low speed wind tunnel of Nanjing University Aeronautics Astronautics at Reynolds number 46000. change rule instantaneous pressure distribution reflects aerodynamic whole model. data temporal file acquired using particle image...

A synthetic jet actuator with double nozzles is developed to control the leeward vortices behind slender body at a high angle of attack. Periodic alternating disturbance nose tip continuously provided by jets. series experiments conducted in low speed and turbulence wind tunnel. The results show that jets can achieve suitable effect which lateral force eliminated. For very attack, are inherently bi-stable state; this state, symmetric distribution formation nearly impossible. However, break...

Jet deflection rate is an essential index in the research of thrust vector control technology. The vectoring jet unsteady flow. In this study, a pulse actuator with adjustable frequency was used to flow field nozzle. experimental results show that same characteristic as separated bubble structure can effectively deflect and adhere wall. main susceptible jet, reach optimal only under excitation specific frequency. transient vortex shedding be destroyed by evenly distribute Coanda wall...

View Video Presentation: https://doi.org/10.2514/6.2023-3750.vid One kind of flow sensing technology for the asymmetric forebody vortices formed at high angles attack and yaw moment slender nose based on finite surface pressure information was proposed. A comprehensive experimental investigation conducted to in LLW-NUAA with a model validate this proposal estimate its ability. The smoke line visualization, five-component bar balance system multi-channels transducers were used investigate...

This study examines boundary layer control and pressure recovery in low Reynolds number supersonic flow with chemical reactions a laser system. Our work prescribes novel method for the optical cavity of system, design diffuser is compared proposed to make stable The characteristics internal reaction heat release were analyzed. Three types experimental pieces designed passively cavity. An active booster-type problem generated by an A platform (SCRP) was established conduct research on docking...