Development of High-Fidelity Techniques to Model Impact Flash and Post-Impact Thermal Signature Prediction and Support Kill Assessment

Initial implementations of the United States missile defense system utilize two primary sensors for kill assessment: RADAR and infra-red (IR) sensors. The post-impact signatures must be accurately modeled to support kill assessment, sensor design, signal processing, and feature extraction. The post-impact RADAR and IR signatures will be, to first-order, governed in the first few seconds by the distribution of particle sizes and densities generated by the fragmentation dynamics, and the kinetic to thermal energy conversion resulting from the hypervelocity impact. We propose to determine the feasibility of using Hybrid Particle-Element (HPE) numerical methods to accurately model both fragmentation and thermofluid dynamics resulting from hypervelocity impacts. The unique Hamiltonian method used in the HPE technique is well suited for simulating large deformations in fragmented media and representing strength effects in a Lagrangian frame. It is not subject to the numerical simulation difficulties associated with the use of pure particle codes, in particular tensile instability and numerical fracture. Our proposed research will demonstrate the potential of HPE methods to offer significant improvements in the numerical simulation of post-impact signatures for MDA applications.