Steps toward 8m honeycomb mirrors. VIII - Design and demonstration of a system of thermal controlDirected jets of ambient temperature air are proposed for the maintenance of low internal temperature gradients and conformity with ambient temperatures in honeycomb-structure borosilicate glass telescope mirrors. The use of greater airflow on thicker sections, to match cooling rates, and the cooling or heating of the internal, back, and edge surfaces of the mirror at the same rate established by convection on the front surface, have been tested on a full scale glass thermal model of a single honeycomb cell from an 8-m diameter mirror. The internal thermal gradient (less than 0.1 C) and ambient-temperature-change lag (less than 0.24 C) ensure minimum image degradation.
Document ID
19870047989
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Cheng, A. Y. S. (Arizona Univ. Tucson, AZ, United States)
Angel, J. R. P. (Steward Observatory Tucson, AZ, United States)