@Article{CiCP-24-791,
author = {},
title = {Incorporation of NURBS Boundary Representation with an Unstructured Finite Volume Approximation},
journal = {Communications in Computational Physics},
year = {2018},
volume = {24},
number = {3},
pages = {791--809},
abstract = {<p style="text-align: justify;">For compressible flow computations, the present paper extends the ETAU
(enhanced time-accurate upwind) unstructured finite volume (FV) scheme to handle
curved domain boundary with better accuracy. For the interior cells in the computational
domain or the boundary cells with straight line boundary, the original ETAU
scheme with second order accuracy in space and time is applied. For those boundary
cells with the curved geometry, a more accurate Non-Uniform Rational B-Spline
(NURBS) representation of the boundary is considered. The NURBS is commonly employed
in computer aided design (CAD) to construct complex geometries. Here, it
yields an exact geometry expression of complex boundary geometry. By combining
ETAU with NURBS, the NURBS incorporated ETAU scheme (NETAU) is proposed for
more accurate geometrical representation and fluxes evaluation. Details of the computing
procedure of the geometry and surface fluxes for cells on the curved boundary,
such as special transformation strategies and merging of ETAU and NURBS, are
introduced and implemented. With NURBS, the NETAU scheme are geometrically
versatile and more flexible. Several two-dimensional (2D) numerical cases are investigated
to demonstrate the performance, computing efficiency and benefits of the NETAU
scheme. The numerical results show that, for flows with low speed and high
Reynolds number, the NETAU scheme provides more accurate pressure distribution
on curved boundary than the original ETAU scheme. Meanwhile, the high-speed flow
case shows that the NETAU scheme is still stable for high Mach number problem with
shocks. Thus, the NETAU scheme potentially provides an accurate tool to describe
complex geometry in computational fluid dynamics (CFD) simulations. It will help
to reduce computational costs and enhances accuracy for flow domain dominated by
complex geometries, with features such as high curvature and sharp edges.</p>},
issn = {1991-7120},
doi = {https://doi.org/10.4208/cicp.OA-2017-0162},
url = {http://global-sci.org/intro/article_detail/cicp/12281.html}
}