Numerical Modeling of High Irradiance Electromagnetic Beam Effects on Composite and Polymer Materials.

摘要

The US Navy faces a growing threat of cheaply produced UAVs and small boats that can attack en masse. Current kinetic defenses to these attacks include missiles and guns (like the CWIS). These defenses fall short because they have very limited magazine size and the cost of using them far outweighs the cost of the target they are defeating. High Energy Lasers (HEL) as Directed Energy Weapons (DEW) provide an alternative. In order to best employ this promising technology the effect of HEL on potential targets needs to be fully understood. The research presented here focused on the effects of HEL on the irradiance (energy per area) and wavelength regime of current interest to the US Navy on simple polymer and carbon fiber reinforced polymer composite materials. A physics-based computer model was developed using COMSOL Multiphysics(trademark) (a computational modeling software) together with material property inputs determined using Differential Scanning Calorimetery (DSC), near infrared (NIR) Fiber Optic Reflectance Spectroscopy (FORS) and the Laser Flash Method (LFM). The model is used to predict the temperature field, heat affected zone (HAZ) and through thickness material removal that HEL irradiation causes in polymer and composite materials. The model predictions were compared to the experimental data and a sensitivity analysis was conducted on the model.