Date of Award
12-1978
Document Type
Thesis
Degree Name
Master of Science in Aeronautical Engineering
First Advisor
Milton E. Franke, PhD
Abstract
The application of pneumatic transmission lines theory to a tube-scanning valve system for unsteady pressure measurements in the AFIT 5-foot wind tunnel is investigated. Transfer gains of various tube-scanning valve configurations were experimentally measured and the validity of a theoretical model verified for a frequency range of 20 Hz to 140 Hz. The selected system having a 0.0625-in. ID flexible tube of 84 in. length connected to a scanning valve was installed in the wind tunnel. Unsteady pressures introduced over an 18 percent airfoil at zero angle of attack were measured with this system. Data were collected for 0, 40, 60, 80, 100, and 150 mph for a frequency range of 30 Hz to 55 Hz. Comparison of theoretical and experimental results for one data point revealed the dependence of the verification of the system measurement accuracy on the wind tunnel speeds and flow perturbation characteristics. Theoretical predictions were verified for 30, 35, and 40 hz only.
AFIT Designator
AFIT-GAE-AA-78D-10
DTIC Accession Number
ADA081906
Recommended Citation
Khan, Mohammed Javed, "A Study of a Wind Tunnel Measurement System for Unsteady Pressures Using Pneumatic Transmission Lines" (1978). Theses and Dissertations. 5526.
https://scholar.afit.edu/etd/5526
Comments
Javed Khan is a 2022 recipient of the AFIT International Alumni Award.
Sourced from the DTIC archival scan of microfiche. Some pages are not legible.