Flow and noise characteristics of a hot supersonic rectangular jet with V-shaped trailing edges
Phys. Rev. Fluids 11, 044606 – Published 16 April, 2026
DOI: https://doi.org/10.1103/ftw5-8jvh
Abstract
The rectangular exhaust nozzles of stealth aircraft typically feature a V-shaped trailing edge (VTE) design. However, no study has focused on the influences of VTEs on the flow and acoustic fields of hot supersonic rectangular jets. In light of this, implicit large-eddy simulations of a rectangular nozzle with and without VTEs are performed at a hot overexpanded condition with a nozzle pressure ratio of 3.0 and a temperature ratio of 3.0. Three VTE nozzles with different deflection angles are studied. Results show that the VTE nozzles are able to prompt the formation of Mach disks, shorten the lengths of potential cores, enhance or suppress the shear-layer mixing in the minor- or major-axis plane, and accelerate the axis switching due to counter-rotating vortex pairs induced along the long-lip sides. The VTE nozzles efficiently suppress or eliminate the screech tone propagating upstream in the minor-axis plane, and the levels of turbulent mixing noise and Mach wave radiation propagating downstream are also substantially reduced, although the broadband noise radiation is amplified in the major-axis plane. The azimuthally integrated overall sound pressure levels show a decrease in the upstream and downstream directions and an increase in the sideline regions. These influences become more significant when the VTEs deflect from inward to outward. The VTE nozzles suffer the penalties of thrust losses, and the total thrust losses arise from the reduced momentum and pressure components for the inward- and outward-deflected VTEs, respectively. The shear-layer oscillation transitions from the flapping mode to a helical mode and then to an irregular pattern, as the VTEs deflect from inward to outward. The wave-number spectra analysis reveals that the VTE nozzles are capable of affecting energy redistribution during wave interactions, leading to the suppression of upstream-propagating guided-jet modes in the fluid-acoustic feedback loop.
