A Stochastic Dynamics Analysis Method Based on Material Point Method Applied in Explosion Shock Engineering

Abstract

The invention provides a material point method-based stochastic dynamics analysis method applied to explosion shock engineering. The method comprises the steps of building an engineering physical model; determining stochastic variables and performing discretization; dividing a background grid for a calculation domain; calculating a node load of the background grid, solving a momentum equation, andcalculating first-order and second-order partial derivatives of an accelerated speed of a grid node and an accelerated speed of a material point to basic stochastic variables; updating the position and speed of the material point and first-order and second-order partial derivatives of the position and speed of the material point to the basic stochastic variables; calculating a strain increment and a spin rate increment of the material point; calculating the density of the material point; according to a constitutive model, updating a stress of the material point and first-order and second-order partial derivatives of a stress function to the basic stochastic variables; according to a state equation model, updating a pressure and first-order and second-order partial derivatives of a pressure function to the basic stochastic variables; and calculating a structure stochastic response result. The defects of a conventional numerical calculation method in researching nonlinear problems of explosion, impact and the like are overcome.

Description

technical field

[0001] The invention relates to a stochastic dynamics analysis method based on a material point method applied in explosion impact engineering, and belongs to the technical field of structural stochastic dynamics analysis. Background technique

[0002] With the development of science and technology and the in-depth understanding of natural things, the calculation method based on deterministic analysis theory can no longer meet the needs of explosion impact research. Therefore, random variables, random processes or random fields are introduced into the calculation to describe the uncertain factors in the calculation of explosion impact, which is of great significance for the reliability research of nonlinear problems such as explosion impact.

[0003] In the analysis and research of problems such as explosion shock, Lagrange method and Euler method are traditionally used. However, when the Lagrange method deals with the explosion impact problem, the grid dist...

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