Progress on Gust Load Alleviation Wind Tunnel Experiment and Aeroservoelastic Model Validation for a Flexible Wing with Variable Camber Continuous Trailing Edge Flap System

This paper discusses a wind tunnel experiment of active gust load alleviation of a flexible wing which took place at University of Washington (UW) in 2019. The experiment performed under a NASA SBIR contract with Scientific Systems Company, Inc (SSCI). The objective of the experiment is to demonstrate active controls of the Variable Camber Continuous Trailing Edge Flap (VCCTEF) system for gust load alleviation and realtime drag optimization. The wind tunnel model is a 8.2% sub-scale Common Research Model (CRM) wing. The wing structure is designed to provide a substantial degree of flexibility to represent that of a modern highaspect ratio wing. Eight active control surfaces are employed in the VCCTEF. A new gust generator system was designed and installed by UW under a sub-contract with SSCI. The first test entry started in July 2019 and ended in September 2019. During this test entry, many significant issues were found with the hardware and software. The significant issues with the servos prevented the test objective from being completed. A follow-up second test entry in 2020 is being planned. The wing system is being repaired by SSCI. This paper reports on the progress of this experimental effort and the aeroservoelastic (ASE) model validation which was conducted during the test entry. ∗Senior Research Scientist and Technical Group Lead, Intelligent Systems Division, nhan.t.nguyen@nasa.gov †Aerospace Engineer, Intelligent Systems Division, nicholas.b.cramer@nasa.gov ‡Aerospace Engineer, Intelligent Systems Division, kelley.e.hashemi@nasa.gov §Aerospace Engineer, Intelligent Systems Division, michael.c.drew@nasa.gov ¶Aerospace Engineer, Intelligent Systems Division, juntao.xiong@nasa.gov ‖Graduate student, William E. Boeing Department of Aeronautics and Astronautics, tmundt94@uw.edu ∗∗Affiliate Associate Professor, William E. Boeing Department of Aeronautics and Astronautics, mmor@uw.edu ††Boeing Endowed Professor, William E. Boeing Department of Aeronautics and Astronautics, eli@aa.washington.edu ‡‡Lead Research Engineer, Scientific Systems Company, Inc., joseph.jackson@ssci.com Lead Integration Engineer, Scientific Systems Company, Inc., rwise@ssci.com Senior Research Engineer, Scientific Systems Company, Inc., Abraham.Shultz@ssci.com Principal Research Engineer and Senior Group Leader, Scientific Systems Company, Inc., jovan@ssci.com

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