27cf51c5-373e-4ed6-e063-0937940a852b English nonGeographicDataset non geographic dataset British Geological Survey +44 115 936 3100 Environmental Science Centre,Keyworth NOTTINGHAM NOTTINGHAMSHIRE NG12 5GG United Kingdom enquiries@bgs.ac.uk pointOfContact 2026-05-03 UK GEMINI 2.3 http://data.bgs.ac.uk/id/dataHolding/13608316 MFIX simulation input and output files for the study of particle laden saline gravity currents 2024-11-13 creation http://data.bgs.ac.uk/id/dataHolding/13608316 MFIX (Multiphase Flow with Interphase eXchanges) simulation input files and raw particle output files. Description of files 1. The directory "MFIX_Setup" contains the MFIX simulation input files for the two simulations Exp19 and Exp35. (MFIX input file (input and boundary conditions) *mfx & MFIX subroutines (*f) and geometry *stl) 2. The directory "time-averaged_slices" contain the time-average slices as *vtu files for Exp19 and Exp35 that can be opened using Paraview (open-source software). 3. The directory "depth-averaged and time-averaged data" contains the python code that reads the depth- and time-averaged data. Note the simulations were run with MFIX-20. The two simulation (Exp19 and Exp35) are 3D two-fluid model (TFM) numerical simulations of liquid-particle mixture, where the fluid and particles are saline water and silica particles, respectively. The finite-volume method is used to solve the mass, momentum and energy equations of the two phases and the solid-fluid coupling is done using drag and pressure terms. The MFIX code that is modified from the core code from the Department of Energy (DOE) is all present. The missing core code can be downloaded from the DOE department https://mfix.netl.doe.gov/. Eric Breard University of Edinburgh not available originator Josef Dufek University of Oregon not available originator Matteo Cerminara Istituto Nazionale di Geofisica e Vulcanologia not available originator Enquiries British Geological Survey United Kingdom not available distributor Enquiries British Geological Survey United Kingdom not available pointOfContact notApplicable https://resources.bgs.ac.uk/images/geonetworkThumbs/27cf51c5-373e-4ed6-e063-0937940a852b.png Geology GEMET - INSPIRE themes, version 1.0 2008-06-01 publication Pyroclastic rocks Lava flows Rheology Volcanoes BGS Thesaurus of Geosciences 2022 revision NGDC Deposited Data Citable Data dataCentre NERC_DDC otherRestrictions restricted The dataset has been formally approved by BGS for access by external clients under a BGS Digital Data Licence, issued via BGS's IPR Section. The dataset must not be provided to, or be accessible by, an external client until the IPR Section confirms that signed licence documentation is in place. Refer to the IPR Section (DigitalLE@bgs.ac.) if further advice is required.. Constraint applies until 2025-06-01 otherRestrictions The copyright of materials derived from the British Geological Survey's work is vested in the Natural Environment Research Council [NERC]. No part of this work may be reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the prior permission of the copyright holder, via the BGS Intellectual Property Rights Manager. Use by customers of information provided by the BGS, is at the customer's own risk. In view of the disparate sources of information at BGS's disposal, including such material donated to BGS, that BGS accepts in good faith as being accurate, the Natural Environment Research Council (NERC) gives no warranty, expressed or implied, as to the quality or accuracy of the information supplied, or to the information's suitability for any use. NERC/BGS accepts no liability whatever in respect of loss, damage, injury or other occurence however caused. Either: (i) the dataset is made freely available, e.g. via the Internet, for a restricted category of use (e.g. educational use only); or (ii) the dataset has not been formally approved by BGS for access and use by external clients under licence, but its use may be permitted under alternative formal arrangements; or (iii) the dataset contains 3rd party data or information obtained by BGS under terms and conditions that must be consulted in order to determine the permitted usage of the dataset. Refer to the BGS staff member responsible for the creation of the dataset if further advice is required. He / she should be familiar with the composition of the dataset, particularly with regard to 3rd party IPR contained in it, and any resultant use restrictions. This staff member should revert to the IPR Section (ipr@bgs.ac.uk) for advice, should the position not be clear. English geoscientificInformation 2023-05-01 2023-12-01 DAT witheld VELOCITY* and FORCES* files witheld Enquiries British Geological Survey United Kingdom not available distributor https://webapps.bgs.ac.uk/services/ngdc/accessions/index.html#item186552 WWW:DOWNLOAD-1.0-http--download Data download https://doi.org/10.5285/3f772a04-bab2-4952-99ef-49c54e8032de WWW:LINK-1.0-http--related Citation Information - Digital Object Identifier (DOI) Breard, E., Cerminara, M., Dufek, J. (2024). MFIX simulation input and output files for the study of particle laden saline gravity currents. NERC EDS National Geoscience Data Centre. (Dataset). https://doi.org/10.5285/3f772a04-bab2-4952-99ef-49c54e8032de information nonGeographicDataset non geographic dataset INSPIRE Implementing rules laying down technical arrangements for the interoperability and harmonisation of Geology 2011 publication See the referenced specification false Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 publication See http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2010:323:0011:0102:EN:PDF false Pyroclastic Density Currents (PDCs) are among the most hazardous geological phenomena, posing challenges for predicting their impacts during eruptions. PDCs are complex, multiphase flows where density stratification significantly influences mixing, deposition, and runout. Simplified models like box models and depth-averaged approaches often assume vertically well-mixed currents, but the impact of these assumptions on mobility has been a focus of recent studies. To explore the effects of density stratification and buoyancy reversal on PDC behavior, we conducted 3D multiphase flow simulations based on heated particle-laden saline water experiments. Results showed distinct behavior for buoyant and non-buoyant currents: buoyant currents exhibited a unique density profile with a minimum at the nose, while non-buoyant currents followed typical Rousean stratification. These differences arise from interactions between density stratification and thermal buoyancy, which affect flow runout. Our findings reveal that fluid buoyancy slows particle settling, enhances vertical mixing, and limits spanwise spreading, aligning with experimental observations. However, the bulk Richardson number fails to accurately describe entrainment in these flows, suggesting a need to refine parameterization in depth-averaged models to better capture the transient nature of PDCs and improve hazard predictions.