UC Davis

The proper construction of aerodynamic databases to support an ascent vehicle during the development phases, and flight, is a difficult task. It encompasses many different flight regimes and several types of aerodynamic coefficient data. The focus of this work addresses integrated force and moment, line load, and surface pressure aerodynamic databases covering the ascent phase of the vehicles flight. In particular, the work deals with a missing component in the uncertainty quantification of these databases, in which existing processes are able to estimate integrated aerodynamic coefficient uncertainty, however estimating an equivalent uncertainty for corresponding distributed loads is not done. The phrase "distributed loads" is used to refer to both line load and surface pressure data, as opposed to the scalar-valued integrated aerodynamic coefficients.

The primary motivation of this work was to create a method that could generate uncertain distributed loads that are consistent with the quantified uncertainty in the integrated aerodynamic coefficients, while also being consistent with the statistical distributions of known data. A brief motivation and outline is included, before Chapter 2 introduces required background concepts. The methods developed for this work are described in Chapter 3 along with a brief survey of similar published works. The methods are validated and tested in a simulated uncertainty scenario, using both line load and surface pressure data, which are presented in Chapter 4. These results showed that the method using a multivariate normal copula was the most successful of the presented methods. Discussions of the performance of the methods in the various results is also included in Chapter 4, with summarizing conclusions and future work included in Chapter 5.