Nils Svanstedt

Large Eddy Simulation of High-Reynolds-Number Wall Bounded Flows

Large Eddy Simulation (LES) of wall-bounded flows becomes prohibitively expensive at high Reynolds (Re) numbers if one attempts to resolve the small but dynamically important vortical structures in the near-wall region. The LES wall-boundary condition problem is thus to account for the effects of the nearwall turbulence between the wall and the first node and its transfer of momentum to the wall. Here we state the problem and give a brief overview of methods currently in use, and possible future methods. To illustrate the problem and quantify the accuracy of some of the models we present a few results from test cases ranging from fully developed turbulent channel flows to three-dimensional problems of practical engineering interest.

Multiscale stochastic homogenization of monotone operators

Multiscale stochastic homogenization is studied for divergence structure parabolic problems. More specifically we consider the asymptotic behaviour of a sequence of realizations of the form

Correctors for the Homogenization of Monotone Parabolic Operators

\frac{\partial u^\omega_\varepsilon}{\partial t}-

Asymptotic analysis for a weakly damped wave equation with application to a problem arising in elasticity

div

A one-population Amari model with periodic microstructure

(a(T_1(\frac{x}{\varepsilon_1})\omega_1, T_2(\frac{x}{\varepsilon_2})\omega_2 ,t, D u^\omega_\varepsilon))=f.

Convergence of quasi-linear hyperbolic equations

It is shown, under certain structure assumptions on the random map

Periodic homogenization of strongly nonlinear reaction–diffusion equations with large reaction terms

a(\omega_1,\omega_2,t,\xi)

Deterministic homogenization of quasilinear damped hyperbolic equations

, that the sequence

G-convergence of Dirac operators

\{u^\omega_\e}

Multiscale homogenization of the Navier-Stokes equation

of solutions converges weakly in