Global modes of variable-viscosity two-phase swirling flows and their triadic resonance

S Schmidt, K Oberleithner - Journal of Fluid Mechanics, 2023 - cambridge.org
The linear and nonlinear dynamics of two-phase swirling flows produced by the Grabowski–
Berger profile under the influence of a viscosity stratification are investigated. We perform …

On the relevance of the runner crown for flow instabilities in a Francis turbine

JS Müller, F Lückoff, TL Kaiser… - IOP Conference Series …, 2022 - iopscience.iop.org
The precessing vortex core (PVC), also known as vortex rope, in a draft tube of a Francis-99
hydro turbine is investigated. The goal is to increase our comprehension of the root of the …

[HTML][HTML] Characterization of the rotating vortex rope pressure oscillations in a kaplan model turbine draft tube

S Shiraghaee, J Sundström, R Mehrdad… - International Journal of …, 2023 - diva-portal.org
The global demand for electricity generation has been increasing over the recent decades
and is expected to grow steadily. Therefore, activating new energy sources to improve the …

Impact of runner crown shape modifications on the onset of the precessing vortex core

F Lückoff, M Naster, JS Müller, M Sieber… - … Series: Earth and …, 2022 - iopscience.iop.org
In this experimental study, a passive flow control concept is provided to extend the stable
part load operation regime by shifting the rise of the precessing vortex core (PVC), also …

[PDF][PDF] Data-driven identification and modelling of coherent dynamics in turbulent flows

MA Sieber - 2021 - researchgate.net
Ich möchte hier allen danken, die mich im Laufe der letzten Jahre dabei unterstütz haben,
diese Dissertation zu vollenden. Zu aller erst gilt ein sehr großer Dank meiner Frau Laura …

Data-driven prediction of unsteady vortex phenomena in a conical diffuser

S Skripkin, D Suslov, I Plokhikh, M Tsoy, E Gorelikov… - Energies, 2023 - mdpi.com
The application of machine learning to solve engineering problems is in extremely high
demand. This article proposes a tool that employs machine learning algorithms for …

Self-consistent closure modeling for linearized mean field methods

JG von Saldern, JM Reumschüssel, TL Kaiser… - AIAA AVIATION 2023 …, 2023 - arc.aiaa.org
View Video Presentation: https://doi. org/10.2514/6.2023-4351. vid Modeling the coherent
component of the Reynolds stresses to close the linearized mean field equations has …

Identification of a Stochastic Hopf Bifurcation from Stationary Measurement Data of a Turbulent Flow

M Sieber, CO Paschereit, K Oberleithner - Progress in Turbulence IX …, 2021 - Springer
The observation of a Hopf bifurcation in fluid dynamics is commonly associated with the
occurrence of a global hydrodynamic instability. The increase of a control parameter above …

[PDF][PDF] FELiCS: Finite Element Linearized (Combustion) Solver

K Oberleithner, TL Kaiser - static.tu.berlin
▪ GUI allows for straightforward application to new flow configurations▪ Running on Linux,
Mac-OSX and Windows▪ Discretization completely independent of type of analyis. Only the …