Aerodynamic model identification of the flying V from wind tunnel data

Abstract

The aerodynamic model identification of a novel aircraft configuration known as the “Flying V” is presented. A global longitudinal aerodynamic model is estimated using static wind tunnel data from a 4.6% sub-scale model. The aerodynamic model structure, unknown a priori, is determined from the data using a modified stepwise regression technique. Orthogonal polynomial models using Multivariate Orthogonal Functions and non-orthogonal spline models in the angle-of-attack dimension are defined for the estimation of the measured aerodynamic coefficients. The estimated models are validated against a partition of the data not used for the estimation, which shows that an adequate model fit and good prediction capabilities are attained. Spline models achieve better results in terms of fitting and show a better matching between the estimation and validation data. All estimated models are considered adequate, with a maximum relative Root Mean Square error below 8% for the polynomial models and below 3% for the spline models.