elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Impressum | Kontakt | English
Schriftgröße: [-] Text [+]

Direct Numerical Simulations (DNS) and Large Eddy Simulations (LES) - Theory and Practice - Course Notes

Shishkina, Olga und Wagner, Claus und Schiffer, Stefanie und Sabih, Marwan und Czarnota, Tomasz und Webel, Oliver und Schräder, Daniela und Feldmann, Daniel und Wagner, Sebastian (2011) Direct Numerical Simulations (DNS) and Large Eddy Simulations (LES) - Theory and Practice - Course Notes. Course Notes, Ordner.

Dieses Archiv kann nicht den gesamten Text zur Verfügung stellen.

Kurzfassung

Recently, there has been a surge of interest from the industry in unsteady turbulent flows computations. Most of the Computational Fluid Dynamics (CFD) methods employed so far proceed by solving the Reynolds-Averaged Navier-Stokes (RANS) equations that are based on semi-empirical turbulence models. It is well known, however, that the RANS-based computations of unsteady turbulent flows are not fully reliable. This results in a high demand for the time-consuming and costly experiments in order to verify these CFD predictions. In the future, accurate LES and DNS are expected to gradually take over those validating duties. By doing a DNS, one resolves all relevant spatial and temporal turbulent scales. Similarly, in a LES the complete range of the temporal scales and at least large and moderate spatial scales are resolved. For that reason, the DNS and LES are the most accurate and comprehensive tools for predicting all relevant turbulent processes and investigating the nature of turbulence. In this DNS/LES course we are going to follow the entire route from observing a physical phenomenon to performing DNS and LES, starting from developing physical models and making their governing equations dimensionless. We will discuss the ways of discretizing and developing higherorder schemes, and will learn how to arrange the mesh resolution requirements. After that, we will consider the numerical stability of both explicit and semi-implicit timestepping schemes, as well as the filtering techniques and reliability of the subgrid scale turbulence models needed for the LES. In the practical part of the course, the abovementioned topics will be explored with the help of a free and open source software package Open-FOAM. This will enable the participants to practise the DNS and LES techniques in various flow problems, as well as allowing a continued usage of the same software after finishing the course. In addition to that, some learning programs will be used in order to give the participants a detailed understanding of the effect that the discretization order, mesh resolution and numerical stability have on the quality of the results obtained in a DNS or a LES.

Dokumentart:Tagungsband
Titel:Direct Numerical Simulations (DNS) and Large Eddy Simulations (LES) - Theory and Practice - Course Notes
Autoren:
AutorenInstitution oder E-Mail-Adresse der Autoren
Shishkina, OlgaNICHT SPEZIFIZIERT
Wagner, ClausNICHT SPEZIFIZIERT
Schiffer, StefanieNICHT SPEZIFIZIERT
Sabih, MarwanNICHT SPEZIFIZIERT
Czarnota, TomaszNICHT SPEZIFIZIERT
Webel, OliverNICHT SPEZIFIZIERT
Schräder, DanielaNICHT SPEZIFIZIERT
Feldmann, DanielNICHT SPEZIFIZIERT
Wagner, SebastianNICHT SPEZIFIZIERT
Datum:2011
Band:Ordner
Herausgeber:
HerausgeberInstitution und/oder E-Mail-Adresse der Herausgeber
Wagner, ClausDLR, Institut für Aerodynamik und Strömungstechnik, Fluidsysteme
Name der Reihe:Course Notes
Status:veröffentlicht
Stichwörter:Direct Numerical Simulations (DNS), Large Eddy Simulations (LES)
HGF - Forschungsbereich:Verkehr und Weltraum (alt)
HGF - Programm:Luftfahrt
HGF - Programmthema:Starrflügler
DLR - Schwerpunkt:Luftfahrt
DLR - Forschungsgebiet:L AR - Starrflüglerforschung
DLR - Teilgebiet (Projekt, Vorhaben):L - Simulation & Validierung
Standort: Göttingen
Institute & Einrichtungen:Institut für Aerodynamik und Strömungstechnik > Fluidsysteme
Hinterlegt von: Stephanie Klein
Hinterlegt am:12 Apr 2011 14:35
Letzte Änderung:12 Apr 2011 14:35

Nur für Mitarbeiter des Archivs: Kontrollseite des Eintrags

Blättern
Suchen
Hilfe & Kontakt
Informationen
electronic library verwendet EPrints 3.3.12
Copyright © 2008-2013 Deutsches Zentrum für Luft- und Raumfahrt (DLR). Alle Rechte vorbehalten.