A Digital Data Acquisition System for High Subsonic Speed Wind Tunnels

  • Dr. Salah. J. S. El-Ibrahim Lecturer, College of Aviation Technology, P.O. Box 3357, Hawally 32034, Kuwait
Keywords: Analogue to digital (A/D) card, Data acquisition, Digital to analogue (D/A) card, Hardware/software, Modified (indented) NACA 6410 aerofoils, I0082070, represents indentation extending from 0.20 to 0.70 with a maximum depth of 0.008 at the centre, I0081020, represents an indentation extending from 0.10 to 0.20 with a maximum depth of 0.008 at the centre of indent (all dimensions are relative to the chord length of the aerofoil), Pressure transducer calibration, Scanivalve, Supersonic speed, Transonic speed, Tunnel calibration, VGK code, Wind tunnel

Abstract

The need to reduce time and cost of running high speed (transonic & supersonic) wind tunnels and to obtain reliable experimental data is very essential to the academic and industrial worlds of aviation. Data acquisitioning technology together with the advents in computer programming made the prospects of upgrading old technology wind tunnels (those manually driven and using mercury or water manometers) a reality. Simple hardware and software are available and are cheap and very effective and can be easily installed for the purposes stated. The present paper describes a data acquisition system, suggested and installed, by the author for use on the supersonic wind tunnel at the university of Hertfordshire/UK. The tunnel layout and the acquisition system are described together with some of the validation experimental runs. The experiments were carried out originally as part of the author’s PhD research work investigating the effects of aerofoil surface irregularities at high subsonic speeds using the viscous Garabedian & Korn (VGK) method [1].

References

. Salah.J.S EL-IBRAHIM. “Prediction of the effects of aerofoil surface irregularities at high subsonic speeds using the viscous Garabedian & Korn method”. PhD thesis. Department of Civil Aeronautical and Mechanical Engineering, University of Hertfordshire, U.K., unpublished work,2000.

. "Supersonic Wind Tunnel Operating Manual". Workshop/Aerospace Civil & Mechanical Engineering Department, University of Hertfordshire.

. Hewlett-Packard Company, "Getting Started With HP-VEE", user manual, 4th Ed. May 1998.

. Data Translation, Inc. "DT VPI, version 5", user manual, 2nd Ed. June 1998.

. Philpott, D.R. “Estimation of the influence of aerofoil surface imperfections using the Viscous Garabedian and Korn prediction method”. Department of Civil Aeronautical and Mechanical Engineering, University of Hertfordshire, U.K., unpublished work,1998.

. Taylor, E.R. "Wind tunnel tests on a modified NACA64010 to assess VGK code". Final year major project report, University of Hertfordshire, U.K., 1998.

. Freestone, M.M. "VGK Method for two-dimensional aerofoil sections- part1: Principles and results". Draft Data Item, ESDU international, Oct.1996.

. Garabedian, P.R, Korn, D.G. "Analysis of transonic aerofoils". Communications on pure and applied mathematics, Vol. XXIV, 841-85,1971.

Published
2020-05-23
Section
Articles