Dissecting the Flow Physics of Store-Induced Effects on Wing Aerodynamics and Limit-Cycle Oscillations in Transonic Flows

Abstract

Most aircraft wings have external stores in the form of engines, fuel tanks, or other payloads. Based on the size and location of these stores, the aeroelastic stability of the wing can be modified. This is particularly so for high-performance aircraft which carry multiple combinations of external stores and for which, transonic effects can modify the energy transfer between the flow and wing. While LCOs may occur for clean wings, wings with certain store configurations are found to be more susceptible to LCO. LCOs result in undesirable airframe vibrations that adversely affect a pilot’s ability to function and degrades targeting accuracy for fighter aircraft. The overall objective of the proposed project is to gain deep insights into the aerodynamic interactions between a wing and an underwing store that affect the flutter characteristics of the wing via high-fidelity computational flow models and new data-enabled tools. We will employ, direct numerical simulations (DNS) of subsonic and transonic flows for a canonical 3D configuration of a wing-store combination to answer the following questions- What is the impact of these interactions on the pressure and suction side flow of the wing as well on the dynamics of the shocks, and how do the interactions change with angle-of-attack and Mach numbers into the transonic regime? What are the key aerodynamic interactions between a wing and an underwing store for a sinusoidally pitching wing? How is the energy transfer between the flow and wing affected by key parameters such as reduced velocity, Mach Number, and other key parameters? Finally, what are the dominant nonlinear aerodynamic mechanisms that are responsible for establishing LCOs – is it changes in shock buffeting or other vortex-induced interactions on the suction and-or pressure side of the wing?

Document Details

Document Type
DoD Grant Award
Publication Date
Feb 22, 2024
Source ID
FA95502310010

Entities

People

  • Rajat Mittal

Organizations

  • Air Force Office of Scientific Research
  • Johns Hopkins University
  • United States Air Force

Tags

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Computational Fluid Dynamics (CFD)