Wind Tunnel System for Active Flutter Suppression Research: Overview and Insights

Abstract

The paper describes the development of a new state of the art large wind tunnel model for active flutter suppression studies as well as the supporting techniques used in tests focused on the effects of uncertainty. Design guidelines and the resulting aeroelastic characteristics of the model are covered together with representative test results. Those would allow other researchers working in this area to develop control laws for the new model and evaluate them. A number of important lessons and insight are reported regarding the design of the model, the level of success of commonly used mathematical modelling techniques to capture its behaviour, sources of analysis / test correlation discrepancies, multi-function utilization of control surfaces for both system identification and flutter suppression, active flutter suppression testing safety, and techniques for estimating by tests of the robustness of closed-loop active aeroservoelastic systems. The new system has made it possible to repeatedly "push" the actively controlled model, using various flutter suppression control laws, safely, to the actual flutter limit in tests numerous times. This capability

Development of an Active Wingtip for Aeroelastic Control

“…The results obtained in terms of alleviation were below the numerical values obtained in Section 4.2.1, mainly due to a loss of control surface efficiency in the wind tunnel, as shown in [49,54], which was estimated as a 25% reduction of the transfer function between the IWT rotation and the wing's tip acceleration. This was recovered by applying a scaling factor of 1/0.75 on the SOF gain matrix to compensate for the efficiency reduction.…”

Precision positioning control of wind tunnel centrosome

“…With the aging of the motor and inter-shaft wear, the no-load torque in different rotation directions often changes slightly. According to Equation (1), the discrete time model of the servo system under the torque model can be described as where T m (k) is the intermediate variable.…”

“…With the development of advanced aircraft and aerospace, the higher demand is required for the performance of aerodynamics test equipment. Wind tunnel system is a key platform for aerodynamic experiments of aircraft [1][2][3]. The wind tunnel system with centrosome has the advantages of blocking airflow noise, reducing pressure fluctuation, and improving the quality of flow field [4].…”