Benchmark computations of 3D laminar flow around a cylinder with CFX, OpenFOAM and FeatFlow

Abstract

Numerically challenging, comprehensive benchmark cases are of great importance for researchers in the field of CFD. Numerical benchmark cases offer researchers frameworks to quantitatively explore limits of the computational tools and to validate them. Therefore, we focus on simulation of numerically challenging benchmark tests, laminar and transient 3D flows around a cylinder, and aim to establish a new comprehensive benchmark case by doing direct numerical simulations with three distinct CFD software packages. Although the underlying benchmark problems have been defined firstly in 1996, the first case which was a steady simulation of flow around a cylinder at Re = 20 could be accurately solved first in 2002 by John. Moreover, there is no precisely determined results for non-stationary case, the simulation of transient flow with time varying Reynolds number. The benchmark problems are studied with three CFD software packages, OpenFOAM, Ansys-CFX and FeatFlow which employ different numerical approaches to the discretization of the incompressible Navier-Stokes equations, namely finite volume method, element based finite volume method and finite element method respectively. The first benchmark test is considered as the "necessary condition" for the software tools, then they are compared according to their accuracy and performance in the second benchmark test. All the software tools successfully pass the first test and show well agreeing results for the second case such that the benchmark result was precisely determined. As a main result, the CFD software package with high order finite element approximation has been found to be computationally more efficient and accurate than the ones adopting low order space discretization methods.

High order exactly divergence-free Hybrid Discontinuous Galerkin Methods for unsteady incompressible flows

“…We observe that we can achieve the same level of accuracy as the results in [59] (and [60]) with a computing time which is dramatically smaller. We note that the computing time per degree of freedom is actually worse than in [59]. Nevertheless, the same accuracy is achieved with much less degrees of freedoms using the high order method (k > 2), s.t.…”

“…our computations exceed the performance results in the literature. In the study [59] one of the conclusions is that their third order method (Q 2 /P disc 1 ) is much more efficient compared to lower order methods. We extend this conclusion in the sense that the use of even higher order discretizations, i.e.…”

“…Finally, in section 4.5 we discuss a three-dimensional, and hence computationally demanding, benchmark problem from [58]. We compare accuracy and run-time performance to the data of the studies in [58,59,60].…”

Complementary numerical–experimental benchmarking for shape optimization and validation of structures subjected to wave and current forces

“…Concerning flows around a structure, the cylinder is arguably the best documented reference problem, including studies at various flow conditions, orientations and aspect ratios (e.g. [48,9,40,18,41,55,56,3]). For computational wind engineering applications, the Silsoe cube, a 6 m cube exposed to a physical wind field, has been studied vigorously both experimentally and numerically (e.g.…”

An adaptive numerical method for free surface flows passing rigidly mounted obstacles

“…Computed drag (left) and lift (right) coefficients dependence on time versus reference data from[1].…”