Accession Number:

ADA558277

Title:

Accurate Modeling of Stability and Control Properties for Fighter Aircraft from CFD

Descriptive Note:

Master's thesis

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT

Personal Author(s):

Report Date:

2012-03-01

Pagination or Media Count:

196.0

Abstract:

Difficulties in obtaining accurate Stability and Control SC data for nonlinear regions in the flight envelope early in the design phase often lead to costly fixes late in the acquisition process. Work examined herein addresses this problem by utilizing recent advances in Computational Fluid Dynamics CFD to create a high-fidelity database before any parts have to be physically produced. In combination with CFD, System Identification SID is used to characterize the SC characteristics of aircraft by some Reduced Order Model ROM. The method of obtaining enough data in the right places, via some optimized maneuver, to create an accurate ROM is the main focus of this work. A series of metrics was created and validated to help identify the quality of any maneuver before it is even run. To validate the metrics, seven different maneuvers were generated, run, and used to create models. These models are then evaluated against sets of results from validation maneuvers to show the accuracy of modeling a given regressor space -- the regressor space being the required variations of the model variables angle of attack, pitch rate, etc.. From the validated metrics, the best maneuver for creating the most accurate model of a given grid within a specified regressor space is defined.

Subject Categories:

  • Aerodynamics
  • Attack and Fighter Aircraft
  • Computer Programming and Software
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE