Aerodynamic Analysis Based on Challenging Minisatellite Payload Satellite Lift-to-Drag Measurements

Abstract

A lift-to-drag ratio analysis is performed based on accelerometer measurements made by the Challenging Minisatellite Payload satellite to investigate the nature of gas-surface interactions taking place in orbit. The results described are for the November 2002 satellite yaw maneuver. At this time, the satellite flew at a mean altitude of 407 km. Two types of gas-surface interaction are considered in the analysis. The first is a cosine (fully diffuse) reflection model with incomplete energy accommodation. The second is a blended cosine reflection model having full accommodation combined with a fraction of quasi-specular reflection having an accommodation coefficient dependent on the surface material. It is found that the fully diffuse model best reproduces the satellite data during the yaw maneuver, and that the accommodation coefficient is approximately 0.89 during this time.

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