SPHERE DRAG MEASUREMENTS IN AN AEROBALLISTICS RANGE AT HIGH VELOCITIES AND LOW REYNOLDS NUMBERS
Abstract
The drag coefficients of spheres for Re2 > 10 to the 4th have been measured in the velocity range 3000 < V sub infinity < 21,000 ft/sec with an accuracy of approximately + or - 1.5 percent. In addition, successful techniques for manufacturing and launching ultralightweight spheres (densities approaching 1 lb/cu ft) have resulted in the ability to measure sphere drag coefficient in the velocity range 3000 < V sub infinity < 12,000 ft/sec and Reynolds number range 3 < Re2 < 10 to the 6th, with an accuracy of approximately + or - 4 percent. This wide range of operating conditions has made it possible to study the initial departures of sphere drag coefficient from the high Reynolds number, continuum level and also to make measurements at free-stream Knudsen numbers approaching 1.0. The results of the tests at the low Reynolds numbers are shown to be consistent with the results obtained in other low- density, hypersonic-flow facilities.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1966
- Accession Number
- AD0633278
Entities
People
- A. B. Bailey
Organizations
- Arnold Engineering Development Complex