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arXiv · 1102.0111

Thermal characteristics of a classical solar telescope primary mirror

Ravinder K Banyal·B. Ravindra
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Abstract

We present a detailed thermal and structural analysis of a 2m class solar telescope mirror which is subjected to a varying heat load at an observatory site. A 3-dimensional heat transfer model of the mirror takes into account the heating caused by a smooth and gradual increase of the solar flux during the day-time observations and cooling resulting from the exponentially decaying ambient temperature at night. The thermal and structural response of two competing materials for optical telescopes, namely Silicon Carbide -best known for excellent heat conductivity and Zerodur -preferred for its extremely low coefficient of thermal expansion, is investigated in detail. The insight gained from these simulations will provide a valuable input for devising an efficient and stable thermal control system for the primary mirror.

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Ravinder K Banyal, B. Ravindra. 2011-02-01. Thermal characteristics of a classical solar telescope primary mirror. https://doi.org/10.1016/j.newast.2011.01.003

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