Conservative static load methodologies have been devised to design equipment against postulated hydrogen detonation. However, these methodologies do not address the dynamic response of the system. Moreover, dynamic response methodologies can be used in lieu of static analyses, if the moving pressure profile due to detonation corresponds to the Chapman-Jouguet pressure and velocity. This moving pressure profile can be applied to a finite element model (FEM) in several ways. One approach is to develop the moving pressure profile by combining the Chapman-Jouguet model of an ideal detonation with the Taylor-Zeldovich [6] similarity solution to obtain an analytic solution to the flow field behind a steadily propagating detonation in a tube. This approach is robust and forgoes modeling the complex physics associated with transitioning from deflagration to detonation and the specific chemical kinetics associated with the gaseous species involved. In another approach, a Lagrange-Arbitrary Lagrange Eulerian (ALE) Model can be used. This type of modeling uses both implicit and explicit constitutive equations that are suitable for simulating fluid structure interaction (FSI) and the disintegration of materials. The method can be exemplified as state variables from the motion of a Lagrange mesh being advected to that of the background ALE mesh. Parts that flow in the ALE mesh interact with the Lagrange structure. However, direct FSI is through specification of the ALE FSI projection card. The ensuing FSI is solved and the state variables of the Lagrange mesh are adjusted for the next iteration. In this scheme the chemical kinetics associated with the detonation of specific mixtures of gaseous species can be considered.
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