We are engaged in a comprehensive effort to understand and model the initiation and growth of laser damage initiated by surface contaminants. This includes, for example, the initial absorption by the contaminant, heating and plasma generation, pressure and thermal loading of the transparent substrate, and subsequent shockwave propagation, "splashing"

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The three-dimensional finite-element thermal analysis of enclosure radiation problems requires the calculation of the geometric surface-co-*surface radi ation view factors.The view factors can be calcu lated by either area or line integration algorithms. This paper addresses the implementation, accuracy, and computational time involved in using these algor ithms. Additionally, an algorithm to identify shadowing surfaces and methods to adjust the calculated view factors for increased accuracy are presented.

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A nonlinear optimization approach is used to determine the minimum weight design for radiating fin arrays used in space applications. Straight and circular fins of rectangular and triangular profile are considered for emissivities in the range of 0.8 to 1.0. The heat transfer analysis includes fin to fin and fin to base radiative interactions. The results, presented in graphical form, give the optimum geometries for the profiles considered in terms of dimensionless parameters. Thus, for specified values of heat transfer rate, base cylinder surface temperature and thermal properties of the fin material, these curves may be used to design minimum weight fin arrays. Two numerical examples are given.