Corrected Stabilized Non-conforming Nodal Integration in Meshfree Methods
A novel approach is presented to correct the error from numerical integration in Galerkin methods for meeting linear exactness. This approach is based on a Ritz projection of the integration error that allows a modified Galerkin discretization of the original weak form to be established in terms of assumed strains. The solution obtained by this method is the correction of the original Galerkin discretization obtained by the inaccurate numerical integration scheme. The proposed method is applied to elastic problems solved by the reproducing kernel particle method (RKPM) with first-order correction of numerical integration. In particular, stabilized non-conforming nodal integration (SNNI) is corrected using modified ansatz functions that fulfill the linear integration constraint and therefore conforming sub-domains are not needed for linear exactness. Illustrative numerical examples are also presented.
KeywordsReproducing kernel particle method Stabilized non-conforming nodal integration Integration constraint Strain smoothing
The support of this work by the US Army Engineer Research and Development Center under the contract W912HZ-07-C-0019:P00001 to the second and third authors and DFG (German Research Foundation) under the grant no. RU 1213/2-1 to the first author is very much appreciated.
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