Wing twist angle predictions using finite element model unit load cases

Abstract

To develop a wing twist angle predictive model, fiber Bragg gratings were installed on a wing and were simulated with rod elements in the wing's finite element model. The finite element model was preliminary used to determine the optimal orientations in which the fibers should be installed to measure the principal strain induced by twist. Simple load cases, created using finite element unit load cases linear combinations, were used to fit parameters of a linear model. Model predictions were first validated on bending and twist simulated load cases and then on experimental twist tests. The predicted wing twist angle relative errors were two times inferior to the targeted error range. This new method seems more accurate than methods presented in previous studies.