Structural Dynamic Considerations for a Hydrocode Analysis of Hypervelocity Test Sled Impacts

Abstract

Numerical analysis of a hypervelocity test sled configuration has been accomplished with structural dynamic analysis and hydrocode analysis for investigating hypervelocity gouging. Previous studies have considered these two aspects of the system primarily apart from each other. It is desired to obtain numerical analysis of hypervelocity gouging that applies directly to a given test sled configuration. An improved analysis may be obtained for this purpose by applying structural dynamic considerations to the hydrocode analysis of slipper impacts on a rail. The primary objective of improving the input model for the hydrocode analysis is to simulate actual field conditions, such as sliding impacts with rail misalignments and on coated rails. The CTH hydrocode input model is adjusted by the addition of an artificial mass to simulate the test sled mass. Three-dimensional impacts are considered in the context of two-dimensional plane strain conditions. Shock reflections are also considered, and the results for sliding impact with a rail misalignment are discussed. The numerical results indicate characteristics seen in field gouges such as jetting and high-temperature effects.