The measurement of unsteady forces and moments on slender bodies oscillating in a wind tunnel

Abstract

An apparatus for the measurement of unsteady aerodynamic reactions on slender bodies is described. It is particularly stated to tests at supersonic speeds. The forces and moments on the model are detected by strain-gauges attached to the model mounting sting and by supplying their bridge circuits with properly phased A.C. of the right frequency, direct meter readings of the stiffness or damping reactions may be obtained. The results of a short series of tests on a cone-cylinder at subsonic Mach numbers and reduced frequency parameters (based on model length) up to 0.06 are given.