Uncertainty propagation in aerodynamic forces and heating analysis for hypersonic vehicles with uncertain-but-bounded geometric parameters

In this study, uncertainties in aerodynamic forces and heating properties of hypersonic vehicles are calculated and analyzed with consideration of uncertain-but-bounded geometric parameters. The aerodynamic shape of a hypersonic vehicle is created with a few geometric parameters containing physical meanings after applying the class and shape transformation (CST) method. Considering uncertainties in geometric parameters caused by manufacturing errors, interval variables are introduced to quantify geometric parameters and a novel interval-based CST method (ICST) is proposed to represent the uncertain aerodynamic shape. By means of hypersonic engineering methods, aerodynamic forces and heating properties of hypersonic vehicles can be predicted. The interval analysis method and novel Bernstein-polynomial-based method for calculating the lower and upper bounds of aerodynamic forces and heating properties are developed. The results of analyzing two numerical examples demonstrate the effectiveness and feasibility of the proposed method and further confirm the necessity of accounting for the uncertainties in geometric parameters when investigating aerodynamic forces and heating properties of hypersonic vehicles. (C) 2018 Elsevier Masson SAS. All rights reserved.