Solar-thermal effects on a shallow spherical shell in orbit

摘要

The effects of solar radiation heating on a large, shallow, spherical shell in orbit are considered. After determining the steady state temperature distribution across the shell thickness, the thermal deformation experienced is estimated as a function of the material properties and the solar incidence angle. There is a harmonic variation of the physical dimensions of the shell as a function of orbital position. The dynamic response of the shell is simulated by utilizing a configuration of twelve control actuator placed on its outer surface and on its edge, and utilizing the LQR design methodology. More significantly, calculations show that the frequencies of transverse vibrations of the shell elastic modes experience considerable deviation from their nominal values due to solar-thermal effects.