A Kriging Based Corrected Potential Flow ROM for Gust Load Calculations

Abstract

A novel aerodynamics reduced order model (ROM) is proposed for gust load calculations on two-and three-dimensional wing geometries at transonic flow conditions. Force estimates from sectional potential flow solutions are taken as inputs to kriging models that predict the aerodynamic loads. The kriging models are trained with coupled aeroelastic CFD calculations of two gust lengths (viz. short and long) which define a range in which the ROM is applicable. An interface is developed to handle the coupling of fluid and structure in the training simulations. The interface ensures conservative transfer of forces from the fluid to the structure and reconstruction of the fluid mesh subject to structural motion. Two test cases are put forward as a means to evaluate ROM: the FFAST Crank aerofoil and the NASA Common Research Model (CRM). In the former case, individual run cost decreased by an order of magnitude and error in the aeroelastic response never exceeded 8%. At the time of writing, the CFD calculations for the CRM case are underway.

Industrially Inspired Gust Loads Analysis of Various-Aspect-Ratio Wings Featuring Geometric Nonlinearity

“…While higher-order structural and aerodynamic methods are sometimes used [24], the computational expense currently limits the application to individual cases of interest rather than large numbers of computations over the whole envelope. Despite the development of aerodynamic reduced order models (ROMs) [25] and corrections to established methods [26,27], the work in this paper is focused on the industrial implications of structural nonlinearities, and as such, a strip theory approach coupled with a nonlinear beam solver is deemed to be sufficient to capture important phenomena without modelling extraneous details.…”