495
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2019   IGPM495.pdf |
TITLE |
Efficient implementation of adaptive order reconstructions |
AUTHORS |
Matteo Semplice, Giuseppe Visconti |
ABSTRACT |
Including polynomials with small degree and stencil when designing very high order reconstructions is surely beneficial for their non oscillatory properties, but may bring loss of
accuracy on smooth data unless special care is exerted. In this paper we address this issue
with a new Central WENOZ (CWENOZ) approach, in which the reconstruction polynomial is
computed from a single set of non linear weights, but the linear weights of the polynomials
with very low degree (compared to the final desired accuracy) are infinitesimal with respect to
the grid size. After proving general results that guide the choice of the CWENOZ parameters,
we study a concrete example of a reconstruction that blends polynomials of degree six, four
and two, mimicking already published Adaptive Order WENO reconstructions [4, 2]. The novel
reconstruction yields similar accuracy and oscillations with respect to the previous ones, but
saves up to 20% computational time since it does not rely on a hierarchic approach and thus
does not compute multiple sets of nonlinear weights in each cell. |
KEYWORDS |
CWENOZ-AO, polynomial reconstruction, weighted essentially nonoscillatory, CWENOZ, adaptive order WENO, finite volume schemes, hyperbolic systems, conservation and balance laws |
DOI |
10.1007/s10915-020-01156-6 |
PUBLICATION |
Journal of Scientific Computing, 83, 6 (2020) |