FORCE MEASUREMENTS IN WIND TUNNELS | ||
International Conference on Aerospace Sciences and Aviation Technology | ||
Article 11, Volume 1, A.S.A.T. CONFERENCE 14-16 May 1985 r CAIRO, May 1985, Pages 141-171 PDF (5.9 M) | ||
Document Type: Original Article | ||
DOI: 10.21608/asat.1985.26471 | ||
Author | ||
K. FRISTEDT | ||
Senior Scientist, AB Rollab, Aviatest/Rollab, Stockholm, Sweden. | ||
Abstract | ||
Experimental aerodynamic information of flying vehicles is obtained through force measurements on captive models in wind tunnels. The most common type of wind tunnel balance today is the strain-gauge balance, which in principle is a spring-balance with electric out-puts. The paper describes the principles of the resistance strain-gauge, and how it can be applied in balances to measure static and dynamic forces. It also discusses proper bridge-wiring to suppress temperature influences and secondary force components. Strain-gauge balances are analog transducers which must be calibrated against known forces and roments.Multi component balances are influened by interac-tions which means that an output of a balance is a function of both a primary and of secondary components. This complicates the process of calibration and a special mathematical model of the balance is used to evaluate calibrations. This model also permits evaluation of aerodynamic forces and moments from wind-tunnel measurements with strain-gauge balances. | ||
Statistics Article View: 295 PDF Download: 244 |