Publicaties

The present study aims to investigate a newly developed multirate time integration technique on aeroelastic simulations of the DTU 10 MW reference wind turbine inside a turbulent atmospheric boundary layer. The turbine is modelled using an actuator line model and a multibody structural solver is employed for the dynamic response. The turbine is studied under cases of laminar flow and a pressure driven boundary layer. Results show that the scheme ...

We introduce a generalized micro-macro Markov chain Monte Carlo (mM-MCMC) method with pseudo-marginal approximation to the free energy that is able to accelerate sampling of the microscopic Gibbs distributions when there is a time-scale separation between the macroscopic dynamics of a reaction coordinate and the remaining microscopic degrees of freedom. The mM-MCMC method attains this efficiency by iterating four steps: (i) propose a new value ...

Time-parallel methods can reduce the wall clock time required for the accurate numerical solution of differential equations by parallelizing across the time-dimension. In this paper, we present and test the convergence behavior of a multiscale, micro-macro version of a Parareal method for stochastic differential equations (SDEs). In our method, the fine propagator of the SDE is based on a high-dimensional slow-fast microscopic model; the coarse ...

Since the 1960's people have made regular claims to the effect of: 'A working nuclear fusion reactor is 20 years away!' This persistent underestimaton of the challenges in the way of building a working fusion reactor can be explained by the following dichotomy between theory and practice: On the one hand, the physical reaction is, in principle, quite simple, i.e., heat hydrogen gas to the point where it ionizes and the ions collide with ...