caa a22 4500 463177681 CHVBK 20180406164830.0 cr unu---uuuuu 170326e20070901xx s 000 0 eng 10.1007/s10596-007-9047-9 doi (NATIONALLICENCE)springer-10.1007/s10596-007-9047-9 An immersed boundary method for compressible multiphase flows: application to the dynamics of pyroclastic density currents [Elektronische Daten] [Mattia de' Michieli Vitturi, Tomaso Esposti Ongaro, Augusto Neri, Maria Salvetti, François Beux] An immersed boundary technique suitable for the solution of multiphase compressible equations of gas-particle flows of volcanic origin over complex 2D and 3D topographies has been developed and applied. This procedure combines and extends different existing methods designed for incompressible flows. Furthermore, the extension to compressible multiphase flows is achieved through a flux correction term in the mass continuity equations of the immersed cells that accounts for density variations in the partial volumes. The technique is computationally accurate and inexpensive, if compared to the use and implementation of the finite-volume technique on unstructured meshes. The first applications that we consider are the simulations of pyroclastic density currents generated by the collapse of a volcanic column in 2D axisymmetric geometry and by a dome explosion in 3D. Results show that the immersed boundary technique can significantly improve the description of the no-slip flow condition on an irregular topography even with relatively coarse meshes. Although the net effect of the present technique on the results is difficult to quantify in general terms, its adoption is recommended any time that cartesian grids are used to describe the large-scale dynamics of pyroclastic density currents over volcano topographies. Springer Science+Business Media, Inc., 2007 Pyroclastic density currents nationallicence Compressible flows nationallicence Cartesian grids nationallicence Finite-volume method nationallicence Immersed boundary method nationallicence de' Michieli Vitturi Mattia Sezione di Pisa, Istituto Nazionale di Geofisica e Vulcanologia, Via della Faggiola, 32, 56126, Pisa, Italy aut Esposti Ongaro Tomaso Sezione di Pisa, Istituto Nazionale di Geofisica e Vulcanologia, Via della Faggiola, 32, 56126, Pisa, Italy aut Neri Augusto Sezione di Pisa, Istituto Nazionale di Geofisica e Vulcanologia, Via della Faggiola, 32, 56126, Pisa, Italy aut Salvetti Maria Sezione di Pisa, Istituto Nazionale di Geofisica e Vulcanologia, Via della Faggiola, 32, 56126, Pisa, Italy aut Beux François Scuola Normale Superiore di Pisa, Pisa, Italy aut Computational Geosciences Springer Netherlands 11/3(2007-09-01), 183-198 1420-0597 11:3<183 2007 11 10596 https://doi.org/10.1007/s10596-007-9047-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10596-007-9047-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- de' Michieli Vitturi Mattia Sezione di Pisa, Istituto Nazionale di Geofisica e Vulcanologia, Via della Faggiola, 32, 56126, Pisa, Italy aut NATIONALLICENCE 700 1- Esposti Ongaro Tomaso Sezione di Pisa, Istituto Nazionale di Geofisica e Vulcanologia, Via della Faggiola, 32, 56126, Pisa, Italy aut NATIONALLICENCE 700 1- Neri Augusto Sezione di Pisa, Istituto Nazionale di Geofisica e Vulcanologia, Via della Faggiola, 32, 56126, Pisa, Italy aut NATIONALLICENCE 700 1- Salvetti Maria Sezione di Pisa, Istituto Nazionale di Geofisica e Vulcanologia, Via della Faggiola, 32, 56126, Pisa, Italy aut NATIONALLICENCE 700 1- Beux François Scuola Normale Superiore di Pisa, Pisa, Italy aut NATIONALLICENCE 773 0- Computational Geosciences Springer Netherlands 11/3(2007-09-01), 183-198 1420-0597 11:3<183 2007 11 10596 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer