TY - JOUR A1 - Knaust, Christian T1 - Modellierung von Tunnelbränden T1 - Modeling tunnel fires – Coupling of fluid and structure N2 - Heute verfügbare Technik ermöglicht es, die Wärmetransportmechanismen im Brand, an der Bauteiloberfläche und im Bauteil mittels CFD zu koppeln. Die Kopplung von Fluid und Struktur wurde am Beispiel eines 100-MW-Tunnelbrands mit CFD (Computational Fluid Dynamics) untersucht. Die instationären Berechnungen wurden mit dem CFD-Programm ANSYS Fluent durchgeführt. Der infolge eines Lkw-Unfalls verursachte n-Heptan-(C7H16)-Brand wurde mit dem Eddy-Dissipation-Verbrennungsmodell modelliert. Das Fluid- und Solid-Gebiet wurden durch ein ‚Interface‘ gekoppelt. Die instationäre Wärmeleitung des Bauteils mit einer Höhe von 0,4 m wurde mit der dreidimensionalen Fourier´schen Wärmeleitungsgleichung modelliert und das instationäre thermische Verhalten des quarzhaltigen Betonbauteils analysiert. Temperaturabhängige Stoffkennwerte wurden berücksichtigt. N2 - The current technology allows the coupling of the temperaturedependent heat transfer mechanisms in case of fire within the structural components and at their surface by means of computational fluid dynamics (CFD). In this paper the thermal coupling of a fluid and a solid region in case of a 100 MW tunnel fire caused by a truck was carried out with CFD. The transient fire simulations were performed with the CFD program ANSYS Fluent. The fire was modeled by the combustion of n-heptane (C7H16) using the eddy dissipation model. The fluid and the solid region were coupled by an interface. The unsteady heat conduction for the 0.4 m thick concrete structure is modeled by using the Fourier heat transfer equation. The transient thermal behavior of quartz containing concrete component was analyzed. Temperature-dependent material properties were considered. KW - Wärmeleitung KW - Berechnungen analytische und empirische KW - ANSYS Fluent KW - Radiation KW - Computational fluid dynamics KW - Temperature dependent properties KW - Analytical and empirical calculations KW - Wärmeübertragung KW - Strahlung KW - Temperaturabhängige KW - Heat transfer KW - Conduction PY - 2016 U6 - https://doi.org/10.1002/bate.201600045 SN - 0932-8351 SN - 1437-0999 VL - 93 IS - 8 SP - 543 EP - 554 PB - Ernst & Sohn Verlag für Architektur und technische Wissenschaften CY - Berlin AN - OPUS4-37211 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Knaust, Christian T1 - Modelling tunnel fires considering the structure, fluid flow and the soot N2 - The time dependent thermal behavior is analyzed with FLUENT for the fluid as well as the solid region (concrete component) in case of a 100 MW n-heptane fire. To study the effect of parameters in mathematical-physical models several sensitivity studies were carried out to investigate the effect on the fluid flow as well as on the component. The influence of soot was additionally considered. FDS simulations as well as empirical calculations considering underlying assumptions are additionally used to examine the plausibility of results from the FLUENT simulations. This is an appropriate method if no experimental results are available. Recommendations are given for choosing parameters in mathematical-physical models e.g. radiation models. The results of the CFD investigations show that considering the influence of soot provides maximum temperatures which were 200 K lower than without soot. T2 - Seventh International Symposium on Tunnel Safety and Security CY - Montréal, Canada DA - 16.03.2016 KW - Heat transfer KW - Conduction KW - Radiation KW - Computational fluid dynamics KW - Temperature dependent properties KW - Model checking KW - Analytical and empirical calculations KW - ANSYS FLUENT KW - FDS PY - 2016 SN - 978-91-88349-11-8 SN - 0284-5172 SP - 617 EP - 628 CY - Boras AN - OPUS4-37688 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -