Numerical Investigation of the Thrust Vectoring Performance of a Bypass Dual Throat Nozzle

Abstract

Abstract Aircraft propulsion systems have become progressively complex due to a recent emphasis on the maneuverability of future fighter aircraft. These systems are capable of providing additional maneuverability to the aircraft. In addition to being able to withstand the high temperatures and pressures generated by modern engines, the systems are also designed to meet the thrust vectoring requirements of various military aircraft. Thrust vectoring (TV) technology allows the nozzle to deflect the primary flow direction to improve the aircraft’s maneuverability. In this study, we analyze the flow characteristics and performance parameters of the bypass dual throat nozzle (BDTN) by varying the bypass angle for a range of nozzle pressure ratios (NPRs). A CFD analysis is carried out using ANSYS FLUENT with the Renormalization Group (RNG) turbulence model to capture the significance of under-expanded and over-expanded jets. The bypass angle varies from 35° to 90° for NPRs ranging from 3∼10. Results show that by decreasing the bypass angle from 90° to 35°, there is a 6% increase in the vectoring angle and an 18% increase in the vectoring efficiency.