TY  - JOUR
A1  - Fischer, Jan-Thomas
A1  - Kowalski, Julia
A1  - Pudasaini, Shiva P.
A1  - Miller, S. A.
T1  - Dynamic Avalanche Modeling in Natural Terrain
JF  - International Snow Science Workshop, Davos 2009, Proceedings ; Proc. ISSW 2009
N2  - The powerful avalanche simulation toolbox RAMMS (Rapid Mass Movements) is based on a depth-averaged
hydrodynamic system of equations with a Voellmy-Salm friction relation. The two empirical friction parameters
μ and �  correspond to a dry Coulomb friction and a viscous resistance, respectively. Although μ and � lack a
proper physical explanation, 60 years of acquired avalanche data in the Swiss Alps made a systematic calibration
possible. RAMMS can therefore successfully model avalanche flow depth, velocities, impact pressure and run
out distances. Pudasaini and Hutter (2003) have proposed extended, rigorously derived model equations that
account for local curvature and twist. A coordinate transformation into a reference system, applied to the actual
mountain topography of the natural avalanche path, is performed. The local curvature and the twist of the
avalanche path induce an additional term in the overburden pressure. This leads to a modification of the Coulomb
friction, the free-surface pressure gradient, the pressure induced by the channel, and the gravity components
along and normal to the curved and twisted reference surface. This eventually guides the flow dynamics and
deposits of avalanches. In the present study, we investigate the influence of curvature on avalanche flow in
real mountain terrain. Simulations of real avalanche paths are performed and compared for the different models
approaches. An algorithm to calculate curvature in real terrain is introduced in RAMMS. This leads to a curvature
dependent friction relation in an extended version of the Voellmy-Salm model equations. Our analysis provides
yet another step in interpreting the physical meaning and significance of the friction parameters used in the
RAMMS computational environment.
KW  - snow
KW  - avalanche
Y1  - 2009
SP  - 448
EP  - 452
ER  - 
TY  - JOUR
A1  - Havermann, Marc
T1  - Effects of the shock tube open-end shape on vortex loops released from it / Kainuma, M. ; Havermann, M. ; Sun, M. ; Takayama, K.
JF  - Shock Waves : Proceedings of the 24th International Symposium on Shock Waves Beijing, China July 11-16, 2004 / edited by Z. Jiang
Y1  - 2005
SN  - 978-3-540-22497-6
SP  - 505
EP  - 510
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Gerhardt, Hans Joachim
A1  - Schönwald, J.
T1  - Eine neue Brandsimulationsvorrichtung
JF  - vfdb-Zeitschrift. 51 (2002), H. 3
Y1  - 2002
SN  - 0042-1804
SP  - 91
EP  - 93
ER  - 
TY  - JOUR
A1  - Blome, Hans-Joachim
T1  - Eine Reise an die Grenzen von Raum und Zeit. Wie die Raumfahrt unser Bild vom Kosmos erweitert.
JF  - DLR- Nachrichten. Mitteilungen des Deutschen Zentrums für Luft- und Raumfahrt. 90 (1998)
Y1  - 1998
SN  - 0937-0420
N1  - Sonderausgabe zum Tag der Raumfahrt 20.8.1998
SP  - 20
EP  - 29
ER  - 
TY  - JOUR
A1  - Dahmann, Peter
A1  - Mager, M.
T1  - Einfluß der Zusammensetzung der abzuscheidenden Verschmutzung auf die Abscheideleistung von Hydraulikfiltern
JF  - Ölhydraulik und Pneumatik. 38 (1994), H. 4
Y1  - 1994
SN  - 0341-2660
SP  - 212
EP  - 214
ER  - 
TY  - JOUR
A1  - Mertens, Josef
T1  - Einige herausragende Ergebnisse des Technologieprogramms "Reduktion des Aerodynamischen Widerstands (RaWid)"
JF  - DGLR-Jahrbuch 1999 Bd. 3
Y1  - 1999
N1  - DGLR-JT99-047
SP  - 1461
EP  - 1468
ER  - 
TY  - JOUR
A1  - Peterson, Leif Arne
A1  - Röth, Thilo
A1  - Uibel, Thomas
T1  - Einsatz von Holzwerkstoffen in Fahrzeugstrukturen
JF  - Bauen mit Holz
Y1  - 2017
SN  - 0005-6545
N1  - gedruckt in der Bereichsbibliothek Bayernallee
IS  - 3
SP  - 32
EP  - 38
PB  - Bruderverlag
CY  - Köln
ER  - 
TY  - JOUR
A1  - Dahl, Günter
A1  - Suttrop, F.
T1  - Engine control and low-NO(x) combustion for hydrogen fuelled aircraft gas turbines
JF  - International Journal of Hydrogen Energy. 23 (1998), H. 8
Y1  - 1998
SN  - 0360-3199
SP  - 695
EP  - 704
ER  - 
TY  - JOUR
A1  - Havermann, Marc
A1  - Seiler, F.
A1  - George, A.
A1  - Leopold, F.
T1  - Enhanced Doppler Picture Velocimetry (DPV) for Planar Velocity Measurements in High-Speed Shock Tunnel Flow / Seiler, F. ; George, A. ; Leopold, F. ; Havermann, M. ; Srulijes, J.
JF  - 10th International Symposium on Flow Visualization : Kyōto, Japan, August 26 - 29, 2002 / sponsored by International Flow Visualization Society . [Chairman:] Toshio Kobayashi
Y1  - 2002
SN  - 4906497829
N1  - International Symposium on Flow Visualization ; (10 ; 2002.08.26-29 ; Kyōto)
PB  - Visualization Society of Japan
CY  - Kyoto
ER  - 
TY  - JOUR
A1  - Tekin, Nurettin
A1  - Ashikaga, Mitsugu
A1  - Horikawa, Atsushi
A1  - Funke, Harald
T1  - Enhancement of fuel flexibility of industrial gas turbines by development of innovative hydrogen combustion systems
JF  - Gas for energy
N2  - For fuel flexibility enhancement hydrogen represents a possible alternative gas turbine fuel within future low emission power generation, in case of hydrogen production by the use of renewable energy sources such as wind energy or biomass. Kawasaki Heavy Industries, Ltd. (KHI) has research and development projects for future hydrogen society; production of hydrogen gas, refinement and liquefaction for transportation and storage, and utilization with gas turbine / gas engine for the generation of electricity. In the development of hydrogen gas turbines, a key technology is the stable and low NOx hydrogen combustion, especially Dry Low Emission (DLE) or Dry Low NOx (DLN) hydrogen combustion. Due to the large difference in the physical properties of hydrogen compared to other fuels such as natural gas, well established gas turbine combustion systems cannot be directly applied for DLE hydrogen combustion. Thus, the development of DLE hydrogen combustion technologies is an essential and challenging task for the future of hydrogen fueled gas turbines. The DLE Micro-Mix combustion principle for hydrogen fuel has been in development for many years to significantly reduce NOx emissions. This combustion principle is based on cross-flow mixing of air and gaseous hydrogen which reacts in multiple miniaturized “diffusion-type” flames. The major advantages of this combustion principle are the inherent safety against flashback and the low NOx-emissions due to a very short residence time of the reactants in the flame region of the micro-flames.
Y1  - 2018
IS  - 2
PB  - Vulkan-Verlag
CY  - Essen
ER  -