SBIR-STTR Award

The objective of the proposed research and development is to develop integrated computational algorithms, and attendant software, to treat fracture and fragmentation of brittle as well as ductile materials, using the Meshless Local Petrov Galerkin nmethod, which is a new pardigm in computational mechanics. The object of Phase I is to develop a three-dimensional code based on the MLPG method. The code will be thoroughly validated through simulations of static and dynamic problems for which analytical and other numerical solutions exist. These problems include: The Boussinesq problem; The Eshelby problem; The problem of non-planar three-dimensional fatigue crack growth in an elastic-plastic solid; and The dynamic Hertzian contact problem

Benefits:
The new code for fracture and fragmentation in brittle as well as ductile materials will alleviate all the shortcomings of the existing finite-element and boundary-element based software. The new code based on the Meshless Local Petrov Galerkin (MLPG) method will become the next-generation software for efficiently and accurately analyzing contact, impact, and penetration problems, and help the Army's Objective Force.

Keywords:
Meshless Method, MLPG Method, contact, impact, penetration, fracture, fragmentation

The Meshless Local Petrov-Galerkin (MLPG) methods will be developed for solving three dimensional nonlinear dynamic problems, with large plastic deformations, to simulate metallic and brittle materials under high-speed impact loads. The general MLPG approach will be applied to the system of governing equations, including the equilibrium equations and energy conservation equations, over the local sub-domains . The nonlinear thermodynamic constitutive models and equation of state models, will be developed to describe the material responses, using the MLPG methods. The damage model will be investigated for characterizing the high-strain-rate material behavior, and for the development of fragmentation, under impact-loading. The contact algorithms, and those for crack initiation and propagation, will be developed for the explicit dynamic code, by incorporating the adaptive node refining and coarsening algorithms. The MLPG computational code will be developed for the full-scale numerical simulation of blast and penetration problems. The graphical pre and post processors will be developed and fully integrated into the high-end industry- products, which are available in the commercial market.

Keywords:
Mlpg Methods, Large Strain Plasticity, Impact And Penetration, Damage Models, Fragmentation, Graphical User Interface (Gui)