ZURUECK HOCH VOR INHALT SUCHEN

» Back to overview
Proposing Institution

Lehrstuhl für Aerodynamik, TU München
Project Manager

Ludger Pähler
Boltzmannstr. 15
85748 Garching
Abstract
The Richtmyer-Meshkov instability (RMI) occurs when the perturbed interface between two fluids with different densities is accelerated impulsively, e.g. by a shock wave. Therefore it is considered as the impulsive limit of the Rayleigh-Taylor instability (RTI). A fundamental understanding of the physics that are driving the mixing process induced by RMI are of crucial importance for many natural and man-made phenomena. The RMI is the reason for the lack of stratification of the supernova 1987a. In engineering application the RMI mechanism is used to enhance the mixing process of fuel with its oxidator. Most published numerical investigations of the RMI are based on solving the Euler equations in two space dimensions and less frequently in three dimensions. Thereby the RMI is often assumed to be a single-species problem as solving the multi-species equations leads to severe numerical difficulties. Further difficulties in the prediction of late-stage mixing arise due to its high sensitivity on initial conditions. The so far limited success in predicting the correct turbulent mixing process during the RMI's later stages in comparison with experimental findings, motivates us to conduct simulations with probability priors to gain a deeper understanding of the sensitivity on the initial conditions. Therefore the full set of two-dimensional multi-species equations is solved with random sampling from said probability prior. In the proposed test project we plan to study the sensitivity of the RMI to initial conditions by combining probabilistic programming based sampling, from custom probability distributions (priors), with detailed numerical simulations of the so-called Reactive Shock-Bubble Interaction (RSBI). The results are also intended to serve as benchmarks for forthcoming full-scale investigations of initial condition sensitivity of said RSBIs. The two-dimensional and three-dimensional implementations have both been verified by Dr. Felix Diegelmann in his three publications on RSBIs in Combustion and Flame, which was simulated on SuperMUC as part of project pr45wa.

Impressum, Conny Wendler