Fast Three-Dimensional Modeling of Atomic Oxygen Undercutting of Protected Polymers

A method is presented to model atomic-oxygen erosion of protected polymers in low Earth orbit. Undercutting of protected polymers by atomic oxygen can occur as a result of the presence of scratch, crack, or pin window defects in the protective coatings. As a means of providing a better understanding of undercutting processes, a fast method of modeling atomic-oxygen undercutting of protected polymers has been developed. Current simulation methods often rely on computationally expensive ray-tracing procedures to track the surface-to-surface movement of individual “atoms.” To reduce the burden of time-consuming calculations, the method introduced replaces computationally demanding individual particle simulations by substituting a model that utilizes both a geometric configuration-factor technique, which collectively governs the diffuse transport of atoms between surfaces, and an efficient algorithm, which rapidly computes the cumulative effects stemming from the series of atomic-oxygen collisions at the surfaces of an undercut cavity. This new method facilitates the systematic study of three-dimensional undercutting by allowing rapid simulations to be made over a wide range of erosion parameters.