European Numerical Mathematics and
Advanced Applications Conference 2019
30th sep - 4th okt 2019, Egmond aan Zee, The Netherlands
08:30   Diverse Applications (Part 1)
Chair: Matthias Möller
25 mins
Inverse methods in illumination optics
Lotte Romijn, Jan ten Thije-Boonkkamp, Wilbert IJzerman
Abstract: We present an efficient numerical algorithm that can be used to solve the generalized Monge-Ampère equation for both a single freeform reflector and lens surface. In this abstract, we briefly illustrate the lens case.
25 mins
Uncertainty Quantification in Wind Power Forecasting
Waleed Alhaddad
Abstract: Reliable wind power generation forecasting is crucial to meet energy demand, to trade and invest. We propose a model to simulate and quantify uncertainties in such forecasts. This model is based on Stochastic Differential Equations whose time-dependent parameters are inferred using continuous optimization of an approximate Likelihood function. The result is a skew stochastic process that simulates uncertainty of wind power forecasts accounting for maximum power production limit and other temporal effects. We apply the model to historical Uruguayan data and forecasts.
25 mins
Numerical solution of traffic flow models
Lukas Vacek, Vaclav Kucera
Abstract: We describe the simulation of traffic flows on networks. On individual roads we use standard macroscopic traffic models. The discontinuous Galerkin method in space and a multistep method in time is used for the numerical solution. We introduce limiters to keep the density in an admissible interval as well as prevent spurious oscillations in the numerical solution. To solve traffic networks, construct suitable numerical fluxes at junctions.
25 mins
The Lattice Boltzmann method and its application to fluid dynamics
Ralf Euser, Kees Vuik
Abstract: As simulation-driven Design becomes more and more popular, there is an increasing demand for advanced numerical simulations. These simulations often require the interaction of fluids with complex geometry to be modeled, in which the resulting fluid dynamics are composed of complicated flow phenomena interacting at different scales. To effectively treat these kind of phenomena, large computational domains including local grid refinements are mandatory. Based on Boltzmann’s transport equation (BTE), the Lattice Boltzmann method (LBM) has become popular tool for simulating fluid dynamics. Due to its intrinsic properties, the method can simulate a range of different flow phenomena. Its computational inexpensiveness and its high locality of calculation allow large computational domains to be simulated, distributed among massively parallel systems, such as GPU accelerators. This presentation will be about LBM and its application to fluid dynamics. The first part of the presentation will focus on the fundamentals behind the method. In the second part, a new type of boundary formulation will be presented for simulating non-reflective outflow conditions. A State of the art multi-node multi-GPU implementation of LBM will be used to model the flow of fluid past blunt objects at high resolutions (Figure 1). A performance comparison will be be carried out between CPU based and GPU based LBM. At final, a real industrial application will be shown, in which the fluid flow over a car body is simulated.