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Use of the Ames Check Standard Model for the Validation of Wall Interference CorrectionsThe new check standard model of the NASA Ames 11-ft Transonic Wind Tunnel was chosen for a future validation of the facility's wall interference correction system. The chosen validation approach takes advantage of the fact that test conditions experienced by a large model in the slotted part of the tunnel's test section will change significantly if a subset of the slots is temporarily sealed. Therefore, the model's aerodynamic coefficients have to be recorded, corrected, and compared for two different test section configurations in order to perform the validation. Test section configurations with highly accurate Mach number and dynamic pressure calibrations were selected for the validation. First, the model is tested with all test section slots in open configuration while keeping the model's center of rotation on the tunnel centerline. In the next step, slots on the test section floor are sealed and the model is moved to a new center of rotation that is 33 inches below the tunnel centerline. Then, the original angle of attack sweeps are repeated. Afterwards, wall interference corrections are applied to both test data sets and response surface models of the resulting aerodynamic coefficients in interference-free flow are generated. Finally, the response surface models are used to predict the aerodynamic coefficients for a family of angles of attack while keeping dynamic pressure, Mach number, and Reynolds number constant. The validation is considered successful if the corrected aerodynamic coefficients obtained from the related response surface model pair show good agreement. Residual differences between the corrected coefficient sets will be analyzed as well because they are an indicator of the overall accuracy of the facility's wall interference correction process.
Document ID
20180000582
Acquisition Source
Ames Research Center
Document Type
Conference Paper
Authors
Ulbrich, N.
(Jacobs Technology, Inc. Moffett Field, CA, United States)
Amaya, M.
(NASA Ames Research Center Moffett Field, CA, United States)
Flach, R.
(NASA Ames Research Center Moffett Field, CA, United States)
Date Acquired
January 17, 2018
Publication Date
January 8, 2018
Subject Category
Aerodynamics
Report/Patent Number
ARC-E-DAA-TN48993
Meeting Information
Meeting: AIAA SciTech 2018 Forum
Location: Kissimmee, FL
Country: United States
Start Date: January 8, 2018
End Date: January 12, 2018
Sponsors: American Inst. of Aeronautics and Astronautics
Funding Number(s)
CONTRACT_GRANT: NNA16BD26C
Distribution Limits
Public
Copyright
Public Use Permitted.
Keywords
wind tunnel wall interferenc
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