On-Board Flow Sensing for Forebody Vortex-Induced Yaw at High Angle of Attack

This study proposes a flow sensing methodology for detecting asymmetric forebody vortices and predicting the yaw moment of a slender nose forebody at high angles of attack, utilizing finite surface pressure information. A comprehensive experimental validation was conducted in the Low-speed and Low-turbulence Wind Tunnel (LLW) facility at Nanjing University of Aeronautics & Astronautics (LLW-NUAA) using a slender forebody model to assess the methodology’s efficacy. Smoke-wire flow visualization, a five-component strain-gauge balance, and multichannel pressure transducers were employed to correlate sectional pressure distributions, flowfield structures, and the model’s lateral force/yaw moment. The Pearson correlation coefficient analysis method was applied to identify optimal characteristic pressure taps for flow sensing. Comparative plot analysis and Pearson correlation calculations determined the second sectional plane (Sec 2, Formula: see text) as the characteristic plane for lateral force/yaw moment sensing, with pressure taps at Formula: see text demonstrating superior yaw moment characterization. Finally, a free-flight model aircraft was developed to validate the onboard flow sensing capability during high-angle-of-attack flight maneuvers.