Abstract

BREDIN, M.S.  and  SKEWS, B.W.. Drag Measurement in Unsteady Compressible Flow Part 1: An Unsteady now Facility and Stress Wave Drag Balance. R&D j. (Matieland, Online) [online]. 2007, vol.23, pp.3-12. ISSN 2309-8988.

The determination of drag forces acting on a body positioned in an unsteady compressible flow is examined. There is very limited data available and the situation is particularly difficult for very fast flow transients such as is encountered by the passage of a shock wave over the body. The development of a rig for producing a range of fast transient flows is described as well as the development of a stress wave drag balance having a response time approximately an order of magnitude better than other balances of this type and able to resolve drag variations in the sub-millisecond range. Results obtained from measurements on spheres and cones are treated in a companion paper.