Wind Tunnel Model Force and Moment Measurement Capability with Corrections for Structural Motion Effects

ABSTRACT: Wind tunnels are used as an important tool to understand the aerodynamics of aircraft. Wind tunnel models are typically instrumented with balances that are capable of measuring the forces and moments that an aircraft will be subjected. Along with measuring these forces and moments knowledge of the aircraft attitude is required in order to resolve the measured components from the balance into their respective aerodynamic coefficients. In particular measurement of the angle of attack (AOA) of the aircraft is critical. Instrumentation such as inclinometers has been used successfully for many years for this task. However, errors in the actual aerodynamic forces have suffered from the effects of model dynamics that produce a bias in both measured forces and AOA. It has been found that this bias can exceed the desired accuracy requirements. Various approaches have been taken to reduce this error and have shown promise. However, some of these approaches are not readily adaptable to all models. This proposal deals with this issue by developing the design of a sensor system that is compact in size and could potentially be integrated as part of the balance. BENEFIT: This research will develop a cost effective method for accurately correcting for inertial effects of measured aerodynamic forces and moments from a wind tunnel model experiencing dynamic conditions, providing the research community with improved data quality and a sensor system that is readily adapted to wind tunnel models and balances.