Electron Beam Densitometer Investigation of Diffusive Separation in Front of a Blunt Body in Low Density Helium-Argon Flows,

Diffusive separation in front of a blunt body in low density binary mixture supersonic flows is of experimental interest for several reasons. Both in low density flows in laboratories, and in rocket born instrumentation studies of planetary atmospheres, sampling probes in conjunction with mass spectrometers can be used to determine flow composition. At present, this flow field has not been described theoretically, and the magnitude and mechanism of probe induced separation effects is not well understood. To aid in understanding such flow fields, partial density measurements were made in the bow shock and stagnation region of a flat ended cylinder in a rarefied helium-argon supersonic free jet flow. Author