ENGINEERING AND CFD

Engineering and CFD

Principal Investigator: Christian Stemmer, Stefan Hickel , Technische Universität München, Fakultät für Maschinenwesen

HPC Platform used: SuperMUC and SuperMUC-NG of LRZ

Local Project ID: pr45tu

Deceleration of a supersonic flow in a channel by shocks and interaction with the turbulent boundary layer leads to the formation of a complex array of shocks, subsonic and supersonic regions, and recirculation zones. In this project, high-fidelity and well-resolved large-eddy simulations (LES) of such a fully turbulent (Reδ≈105) pseudo-shock system were performed and compared with experimental data. Particular attention is paid to the occurrence of flow instabilities (such as shock motion, shock-boundary layer interaction, and symmetry breaking of the shock system), mixing behaviour in the transonic shear layer, and a comparison with sophisticated RANS turbulence models.

Engineering and CFD

Principal Investigator: Stefan Platzer , Institute of Helicopter Technology, Technical University of Munich

HPC Platform used: SuperMUC-NG of LRZ

Local Project ID: pn56lu

Rotorcraft are regularly operating in ground effect over moving ship decks or on hillsides. However, only a very limited amount of research has been done to investigate the complex three-dimensional flow fields in these flight conditions and the resulting changes in rotor performance. Therefore, a hovering rotor in non-parallel ground effect was simulated in this project. URANS CFD simulations were made using various turbulence models to gain insight into the three-dimensional flow field, the rotor tip vortex evolution and the velocity distribution in the rotor plane. Best agreement with available experimental data was seen with a Reynolds stress model. Overall, the flow field was most affected close to the rotor hub and on the uphill side.

Engineering and CFD

Principal Investigator: Michael Manhart , Professorship of Hydromechanics, Technical University of Munich

HPC Platform used: SuperMUC and SuperMUC-NG of LRZ

Local Project ID: pn56ci

In this project the flow in partially-filled pipes is investigated. This flow can be seen as a model flow for rivers and waste-water channels and represents a fundamental flow problem that is not yet fully understood. Nevertheless, there have neither been any high-resolution simulations nor well resolved experiments reported in literature to date for this flow configuration. In this project highly resolved 3D-simulations are performed which help further understanding narrow open-channel and partially-filled pipe flows. The analysis concentrates on the origin of the mean secondary flow and the role of coherent structures as well as on the time-averaged and instantaneous wall shear stress.

Engineering and CFD

Principal Investigator: Barbara Wohlmuth , Lehrstuhl für Numerische Mathematik, Technische Universität München

HPC Platform used: SuperMUC and SuperMUC-NG of LRZ

Local Project ID: pr74ne

Large scale simulations are particularly valuable and important for a better understanding of coupled multi physics problems describing a large class of physical phenomena. This research project focuses on the development of new numerical methods for efficiently solving coupled non-linear and time-dependent fluid flow problems on a large scale. In particular, two applications are considered. Namely, the Navier–Stokes equations coupled to a transport equation describing diluted polymers and geodynamical model problems which involve non-linearities in the viscosity. The goal is to develop new methods for solving these problems, evaluating their performance and scalability, and to perform simulations based on these new methods.

Engineering and CFD

Principal Investigator: Xiangyu Hu , Chair of Aerodynamics and Fluid Mechanics, Technische Universität München

HPC Platform used: SuperMUC and SuperMUC-NG of LRZ

Local Project ID: pr53vu

As a Lagrangian method, Smoothed Particle Hydrodynamics (SPH) has been explored and demonstrated for a wide range of applications. Several open-source frameworks exist for the large-scale parallel simulation of particle-based methods in which the resolution of simulation is fixed. Some preliminary work has also been published to tackle the difficulties encountered in extending codes with adaptive-resolution capability. However, the support for fully parallelized adaptive-resolution in distributed systems is generally still limited in the aforementioned codes. This research project focuses on an alternative approach by introducing a new multi-resolution parallel framework employing several algorithms from previous work.