Predictor of Aircraft Structural Load Due to Buffet

Global Engineering and Materials, Inc., along with its team members, Iowa State University, Technical Data Analysis, Inc., and YB Numerics, Inc., proposes to develop a buffet-induced aircraft structural response and multiaxial fatigue damage prediction software via a hybrid immersogeometric and boundary-fitted (BF) compressible-flow fluid-structure interaction (FSI) simulation and subsequent hybrid time- and frequency-domain multiaxial fatigue damage assessment. The software immersed the majority of the high-fidelity aircraft model into the fluid domain while modeled other critical parts (e.g., horizontal stabilizers) in a BF manner. For the structural description, an IGA-based multi-patch analysis approach is used to accurately model the critical parts while a super-element approach is employed elsewhere with imposed modal superposition. The predicted structural response is then analyzed using a hybrid time- and frequency-domain fatigue damage evaluation module to account for the non-stationarity of the problem. Specifically, a critical plane approach is firstly adopted to identify the fatigue fracture plane, and the entire flight profile is then segmented into stationary and non-stationary parts for fatigue damage evaluation based on frequency-domain and time-domain methods, respectively. The developed software will be validated against existing IAT and flight test data. A machine learning model will be constructed after validation for quick response/damage prediction and eventually integrated into the current IAT system. The developed high-fidelity software “BLAST” is anticipated to be able to quickly and reliably evaluate all flight conditions to isolate fatigue critical spots of an aircraft subjected to a combined normal operational and buffet-induced non-stationary loading.