Enhancing accuracy with a convolution filter : What works and why!

• In this paper we present a simplified discussion of the Smoothness-Increasing Accuracy-Conserving (SIAC) filter. We demonstrate the importance of appropriately initializing the data in order to be able to extract higher orders of accuracy by comparing the nodal and modal forms of a discontinuous Galerkin approximation applied to a simplified cubic polynomial. Using the modal form, we are able to exactly reproduce the cubic polynomial, whereas this reconstruction does not occur using the nodal form. Furthermore, we tie the ability of the filter to extract extra accuracy to its accurate wave propagation properties.

Subject headings

NATURVETENSKAP  -- Matematik -- Beräkningsmatematik (hsv//swe)

NATURAL SCIENCES  -- Mathematics -- Computational Mathematics (hsv//eng)

Keyword

Convolution filtering

Discontinuous Galerkin

Smoothness-increasing Accuracy-conserving (SIAC) filter

Superconvergence

Publication and Content Type

ref (subject category)

art (subject category)