Study on the influence of outflow conditions on the vector control characteristics of wedge-shaped PFTV nozzle

The fluidic thrust vectoring technology holds significant promise for enhancing aircraft maneuverability, agility, and stealth capabilities. Currently, research on passive fluidic thrust vectoring (PFTV) nozzles is predominantly conducted in the absence of external flow, leaving the impact of variations in the external flow velocity and flight attitude on jet deflection and thrust vectoring control characteristics unclear. This paper presents a wind tunnel test model of a wedge-shaped PFTV nozzle powered by an electric ducted fan. The study investigates the nozzle's thrust vectoring angle control characteristics under various internal and external flow conditions, as well as the velocity field distribution of both internal and external flows under typical operating conditions. Results indicate that,at jet velocities of 30-75 m/s (Re = 1.69 × 10⁵～4.22 × 10⁵) and external flow velocities of 10-25 m/s, jet deflection exhibits entrainment and blocking effects on the external flow on both sides of the nozzle, creating a velocity difference. This results in a lateral aerodynamic force that increases the maximum thrust vector angle as the ratio U* of the external flow velocity to the jet velocity increases. As the angle of attack of the nozzle model increases, the greater impact of the external flow on the windward side compared to the leeward side intensifies, leading to smaller deflection angles on the windward side compared to the leeward side.