Engineering Papers⌕ Search

Engineering topics

Gisler, Galen Ross

Publications and source records attributed to Gisler, Galen Ross.

Benchmarking impact hydrocodes in the strength regime: Implications for modeling deflection by a kinetic impactor

The Double Asteroid Redirection Test (DART) is a NASA-sponsored mission that will be the first direct test of the kinetic impactor technique for planetary defense. Here, the DART spacecraft will impact into Didymos-B, the moon of the binary system 65803 Didymos and the resulting period change will be measured from Earth. Impact simulations will be used to predict the crater size and momentum enhancement expected from the DART impact. Because the specific material properties (strength, porosity, internal structure) of the Didymos-B target are unknown, a wide variety of numerical simulations must be performed to better understand possible impact outcomes. This simulation campaign will involve a large parameter space being simulated using multiple different shock physics hydrocodes. In order to understand better the behaviors and properties of numerical simulation codes applicable to the DART impact, a benchmarking and validation program using different numerical codes to solve a set of standard problems was designed and implemented.

79 ASTRONOMY AND ASTROPHYSICS↗

Deep Water Impact Ensemble Data Set

Asteroids of various sizes, speeds, and compositions are zipping around the solar system with potential future Earth engagements. Most of the earth is covered in ocean and impacts would likely occur in deep ocean water. The IEEE SciVis Contest 2018 is dedicated to the visualization and analysis of simulations designed to study asteroid impacts in deep ocean water.

"asteroid impact" meteor "in situ" visualization↗

Los Alamos and Lawrence Livermore National Laboratories Code-to-Code Comparison of Inter Lab Test Problem 1 for Asteroid Impact Hazard Mitigation

The NNSA Laboratories have entered into an interagency collaboration with the National Aeronautics and Space Administration (NASA) to explore strategies for prevention of Earth impacts by asteroids. Assessment of such strategies relies upon use of sophisticated multi-physics simulation codes. This document describes the task of verifying and cross-validating, between Lawrence Livermore National Laboratory (LLNL) and Los Alamos National Laboratory (LANL), modeling capabilities and methods to be employed as part of the NNSA-NASA collaboration. The approach has been to develop a set of test problems and then to compare and contrast results obtained by use of a suite of codes, including MCNP, RAGE, Mercury, Ares, and Spheral. This document provides a short description of the codes, an overview of the idealized test problems, and discussion of the results for deflection by kinetic impactors and stand-off nuclear explosions.

79 ASTRONOMY AND ASTROPHYSICS↗