Aerodynamic drag and geomagnetic perturbations: their modelling and effect on spacecraft dynamics

Aerodynamic drag and geomagnetic perturbations: their modelling and effect on spacecraft dynamics

Noomen, R.

Wakker, K. (mentor)

Aerospace Engineering

Aerospace Engineering

1983-07-01

This study is aimed at the improvement of the modelling of aerodynamic drag, acting on spacecraft. In particular, the fit of the theoretically generated orbit of the GEOS-3 satellite through laser range measurements, obtained by tracking stations all over the world, in various periods of time, is improved. Special attention is paid to the effect of geomagne­tic disturbances on atmospheric density and the modelling of these disturbances. Drag coefficients, obtained in this way, are compared with drag coeffi­cients obtained in windtunnel experiments or calculated by theory; these results proved to be consistently incompatible. The effect of a different drag modelling is examined, both with a speed ratio-dependent drag coefficient and with more recent density models. Streng indications were found that the implementation of the speed ratio effect does not lead to significant improvements, but that the modelling of atmospheric density with the MSIS density model in combination with an alternative interpolation in tables with daily-averaged geophysical parameters may result in an improvement of the orbital fit (reduction of the differences between measured ranges and theoretic ranges, between satellite and tracking stations) by up to 50 percent.

atmospheric drag, Orbit Determination

http://resolver.tudelft.nl/uuid:bdb00e9b-0b3b-41b9-89fe-665bf2293d47

Education repository

master thesis

(c) 1983 Ron Noomen