Wind Tunnel Test And Aeroelastic Model Validation Of Electrical Lift-Thrust Units

Abstract

The increasing interest in multi-propeller electric Vertical Take-Off and Landing aircraft for Advanced Air Mobility has underscored the need for high-fidelity methodologies capable of predicting and analysing complex aerodynamic and structural interactions across a broad frequency range. These interactions are particularly influenced by the variable rotor speed control strategies typically adopted by Lift Thrust Units. Building on previous experimental work, where the aeroelastic model of one and two grounded LTUs was statically validated, this paper employs roving hammer tests and operational modal analysis to identify, and subsequently incorporate into the aeroelastic model, an elastic representation of the LTU support system. The proposed model aims to enhance the correlation between numerically predicted dynamic loads and wind tunnel measurements over a range of operational conditions. Specifically, the paper investigates how the elastic support influences the system's dynamic response and enhances agreement with experimental measurements. Furthermore, the study considers the effect of rotor phase synchronization and demonstrates its significant impact on the loads generated.