Efficient computation of mean drag for the subcritical flow past a circular cylinder using general Galerkin G2

• General Galerkin (G2) is a new computational method for turbulent flow. where a stabilized Galerkin finite element method is used to compute approximate weak solutions to the Navier-Stokes equations directly, without any filtering of the equations as in a standard approach to turbulence simulation. such as large eddy simulation, and thus no Reynolds stresses are introduced, which need modelling. In this paper, G2 is used to compute the drag coefficient c(D) for the flow Past a circular cylinder at Reynolds number Re=3900, for which the flow is turbulent. It is found that it is possible to approximate c(D) to an accuracy of a few percent, corresponding to the accuracy in experimental results for this problem, using less than 10(5) mesh points, which makes the simulations possible using a standard PC. The mesh adaptively refined until a stopping criterion is reached with respect to the error in a chosen output of interest, which in this paper is c(D). Both the stopping criterion and the mesh-refinement strategy are based on a posteriori error estimates, in the form of a space-time integral of residuals times derivatives of the solution of it dual problem, linearized at the approximate solution, and with data coupling to the output of interest.

Subject headings

NATURVETENSKAP  -- Data- och informationsvetenskap (hsv//swe)

NATURAL SCIENCES  -- Computer and Information Sciences (hsv//eng)

Keyword

adaptive DNS/LES

general Galerkin (G2)

adaptive finite element method

duality

a posteriori error estimate

turbulence

large eddy simulation (LES)

direct numerical simulation (DNS)

circular cylinder

Information technology

Informationsteknik

Publication and Content Type

ref (subject category)

art (subject category)