Reduced Order Aerodynamic Loads Modeling of Maneuvering Aircraft
Abstract
The prediction of aerodynamic loads is still a challenging engineering issue for military aircraft designers. Unsteadiness in the flow can lead to uncommanded motion and uncontrollable departure in flight testing. Despite their greatest efforts using the best available predictive capabilities, nearly every major fighter program since 1960 has had costly nonlinear aerodynamic or fluid-structure interaction issues that were not discovered until flight testing. Currently, the use of computational fluid dynamics (CFD) solutions is considered the state of theart in modeling unsteady nonlinear flow physics and offers an early and improved understanding and prediction of aircraft aerodynamic characteristics. Specifically, significant progress has been made by the US Air Force Academy (USAFA) and others in demonstrating the ability of Unsteady Reynolds Averaged Navier-Stokes (URANS) and Delayed Detached Eddy Simulation (ODES) approaches to accurately predict the forces and moments on aircraft maneuvering at the edge of the flight envelope. With the advanced computing techniques, one straight forward way to calculate unsteady aerodynamics forces and moments of a maneuvering aircraft is to develop a full-order mathematical model based on direct solution of discretized Navier-Stokes equations coupled with the dynamic equations governing the aircraft motion. However, a full-order model for Stability and Control (S and C) analysis is computationally very expensive approach since such a model needs a large number of coupled computations for different values of motion frequency and amplitude.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 28, 2012
- Accession Number
- AD1030923
Entities
People
- Mehdi Ghoreyshi
Organizations
- United States Air Force Academy