EFFICIENT STABILIZATION OF THE ADJOINT FOR TURBULENT SEPARATED FLOWS
Abstract
This project will investigate the use of adjoint-based numerical methods for characterizing turbulent, separated flow phenomena and their sensitivity to control inputs. Turbulent flow separation is critical to the performance of flight vehicles. It limits the maximum lift that can be generated for both trimmed and maneuvering flight. Localized separation may lead to unwanted aerodynamic interference or produce unsteady loads that exceed design tolerances. Control of turbulent, separated flow phenomena is therefore desirable, whether through passive shape design or through active flow control. Existing strategies for mitigation and control of separated flows are often based on experience and intuition, exposing a knowledge gap for the design of new vehicle systems. Because separated flows are nonlinear and unsteady, adjoint methods offer an opportunity to discover physical sensitivities and causal relationships that are otherwise inaccessible using standard modal decomposition techniques and stability analyses. High-fidelity numerical simulations of separated flow test cases and stabilized adjoint solutions will be calculated for multiple objective functions. The adjoint costates represent flow structures with the strongest influence on the objective function and indicate both spatial and temporal receptivity. Knowledge of the flow structures associated with specific stall behaviors is crucial for designing control and mitigation strategies. Additionally, measurement-detection of these structures could aide in forecasting turbulent flow separation.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 07, 2023
- Source ID
- FA95502210108
Entities
People
- James Coder
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Tennessee