Some Effects of Vehicle Flow Field on the Capture Efficiency of a Gerdien Capacitor Atmospheric Probe.

Abstract : Wind tunnel tests of a rocket borne upper atmospheric probe for measuring atmospheric charge density are reported. The Gerdien capacitor probe consists of a short section of a co-axial capacitor. This is mounted on pylons from a model of the Tomahawk vehicle. Results are reported for the mach number range 2 to 3 and altitude range 26 to 50 km. Over this range the ratio of mass flow through the probe to mass flow in an equal cross section of the free stream ranged from .69 to .80. Schlieren photographs of the flow are presented. (Author)