Polyhedral Spline Finite Elements

Abstract: Spline functions have long been used in numerically solving differential equations. Recently it revives as isogeometric analysis, which uses NURBS for both parametrization and element functions. In this paper, we introduce some multivariate spline finite elements on general partitions. These splines are constructed by mollifying splines of low smooth order with B-splines. They have both high smooth order and strong approximation power. The low smooth order splines can be chosen flexibly, for example polynomials on individual cells of general polyhedral partitions. Evaluation of such splines is not difficult, so the obtained spline elements are suitable for the collocation method and adaptive computation.