Numerically simulating structural behaviors of a product using explicit finite element analysis with a combined technique of mass scaling and subcycling

摘要

Methods and systems for numerically simulating structural behaviors of a product using explicit FEA with a combined technique of subcycling and mass scaling are disclosed. A FEA model representing a product and a minimum time step size (Δtmin) for a time-marching simulation of the product are specified. N element groups is established with the first element group associated with Δtmin as required minimum time step size, while other element groups with integer multiples of Δtmin according to formula Δti=2i-1Δtmin, n=1, 2, . . . , N. Finite elements are periodically resorted into N element groups based on their new respective Δtcr. To ensure all finite elements in the FEA model are processed at the user specified minimum time step size, proper amount of mass scaling is applied to those finite elements that are or have become too small to maintain a stable solution in the first element group.

主权项

1. A method of numerically simulating structural behaviors of a product using explicit finite element analysis (FEA) with a combined technique of subcycling and mass scaling, said method comprising:
receiving a FEA model and a minimum time step size (Δtmin) in a computer system having an explicit FEA application module installed thereon, said FEA model representing a product defined by a plurality of nodes and a plurality of finite elements with associated material properties and said minimum time step size being the smallest time step size to be used in a time-marching simulation of the product for ensuring the time-marching simulation to be conducted with an overnight computation; establishing N element groups with a first element group associated with said minimum time step size, remaining of the N element groups being associated with integer multiples of said minimum time step size, where N is a whole number greater than one; sorting the finite elements into the N element groups based on respective critical time step sizes of the finite elements; applying mass scaling to maintain a stable solution in the first element group, said mass scaling being applied to each finite element in the first element group having its element critical time step size smaller than the minimum time step size, such that said each finite element is stably processed in the time-marching simulation; and obtaining simulated structural behaviors at a number of major solution cycles and at one or more sub solution cycles within each major solution cycle by conducting the time-marching simulation using the FEA model with the explicit FEA application module executed in the computer system, said explicit FEA application module applying a combined technique of subcycling and mass scaling with periodic resorting of the finite elements based on their new respective element critical time step sizes and with applying mass scaling to maintain a stable solution in the first element group.