Accession Number : AD0286503

Title :   ON MEASURING THE COEFFICIENT OF DRAG OF AN ACCELEROMETER-INSTRUMENTED SPHERE IN A SHOCK TUBE

Corporate Author : NAVAL ORDNANCE LAB WHITE OAK MD

Personal Author(s) : RIESS,M.

Report Date : OCT 1962

Pagination or Media Count : 26

Abstract : The feasibility of measuring the aerodynamic coefficient of drag (C sub D) of a sphere in a shock tube by means of an accelerometer was studied. The method involved mounting an accelerometer within the sphere and measuring its response to a known flow. The range of Mach and Reynolds numbers covered in the tests was limited by the physical parameters of the shock tube used. Based on attenuation and model blockage effects, the tests were limited to a Mach number range of 1.4 to 1.6 and a Reynolds number range of 49,000 to 150,000. A 1.1 in. dia. aluminum sphere was suspended in the test section and 5 shots were made with a constant pressure-ratio across the diaphragm. The values of C sub D reduced from these shots were compared to those found by another experimenter using a ballistics range facility. The agreement, based on Mach and Reynolds numbers, was in most cases of the order of 1 to 4%. (Author)

Descriptors :   *SPHERES, ACCELEROMETERS, DRAG, SHOCK TUBES

Distribution Statement : APPROVED FOR PUBLIC RELEASE