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arXiv · 2101.06497

High-accuracy mesh-free quadrature for trimmed parametric surfaces and volumes

David Gunderman·Kenneth Weiss·John A. Evans
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Abstract

This work presents a high-accuracy, mesh-free, generalized Stokes theorem-based numerical quadrature scheme for integrating functions over trimmed parametric surfaces and volumes. The algorithm relies on two fundamental steps: (1) We iteratively reduce the dimensionality of integration using the generalized Stokes theorem to line integrals over trimming curves, and (2) we employ numerical antidifferentiation in the generalized Stokes theorem using high-order quadrature rules. The scheme achieves exponential convergence up to trimming curve approximation error and has applications to computation of geometric moments, immersogeometric analysis, conservative field transfer between high-order curvilinear meshes, and initialization of multi-material simulations. We compare the quadrature scheme to commonly-used quadrature schemes in the literature and show that our scheme is much more efficient in terms of number of quadrature points used. We provide an open-source implementation of the scheme in MATLAB as part of QuaHOG, a software package for Quadrature of High-Order Geometries.

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David Gunderman, Kenneth Weiss, John A. Evans. 2021-01-16. High-accuracy mesh-free quadrature for trimmed parametric surfaces and volumes. https://doi.org/10.1016/j.cad.2021.103093

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