Quantification of the Uncertainties for the Ares I A106 Ascent Aerodynamic Database

Abstract

https://ntrs.nasa.gov/search.jsp?R=20100036626 2019-03-23T01:47:26+00:00Z American Institute of Aeronautics and AstronauticsThis material is declared a work of the U.S. Government and is not subject to copyright protection by the United States.

Detailed Uncertainty Analysis of the Ares I A106 Liftoff/Transition Database

“…Along with developing the nominal aerodynamic coefficients, the aero team conducted a detailed uncertainty quantification (UQ) analysis to estimate the database uncertainties and provide recommendations for the uncertainty modeling during dispersion analyses and risk assessment. The basic UQ methodology used for the A106 Liftoff/ Transition DB was similar to the analyses performed for several other Ares I aerodynamic databases, such as the A106 Ascent Force and Moment (AFMA) Database [8].…”

Assessment of CFD-based Response Surface Model for Ares I Supersonic Ascent Aerodynamics

“…26, while the details of the uncertainty analysis are presented in Ref. 10. This paper will briefly summarize the general procedures and highlight some modifications to the data made for the current comparisons, but the reader is directed to the reference documents for additional details.…”

“…The experimental uncertainty for the WT-based DB presented in Ref. 10 depends only on the estimated data repeatability, which the UQ team computed using data from both the A106 test in the UPWT as well as data from previous Ares I WT tests in UPWT. Replicate runs were performed throughout each WT test, often with several days or significant configuration changes occurring between replicates, so the repeatability estimated by the UQ team could also be referred to as reproducibility based on the nomenclature of the US Guide to the Expression of Uncertainty in Measurement.…”

“…The uncertainty model presented here for the CFD-based Supersonic A106 AFMA DB follows the general methodology used for the WT-based Supersonic A106 AFMA DB. 10 The UQ team estimated uncertainties for significant sources of uncertainty in the database development process. In general, these sources can be split into three main categories: (1) input data uncertainty, (2) database modeling (DBM) uncertainty, and (3) database interpolation (DBI) uncertainty.…”

“…The DB team computed a simple linear model to adjust the final WT-based A106 AFMA DB to simulate FLT Re conditions based on CFD data at WT and FLT Re. 10 The DB Team also computed the inverse of that linear model and applied it to the A106 FLT Re CFD solutions to create "approximate" WT Re solutions. The general form of this correction is shown in Eq.…”