Simulation Environment for Onboard Fire and Smoke Propagation Model

1. Simulation Environment for Onboard Fire and Smoke Propagation Model Tomasz Haupt, Greg Henley, and BhargaviParihar Center for Advanced Vehicular Systems, Mississippi State University 1. Introduction 3. FireGUI Simulation Environment 4. Results The ability to quickly and accurately predict fire and smoke (or other airborne particles) spread in a vessel can be critical to enable the vessel to continue its mission. A fire, whether initiated by enemy, terrorist, or other accidental cause, may hinder or totally disable the vessel if not contained quickly and efficiently. The FireGUI software, reads the information from the database to display a 3D and floorplan view of a geometry. Fire source(s) can be specified as well as states of various objects, then the simulation is started and the results are displayed as the simulation is run . • FireGUI Features: • 3D ship view with rotate, zoom, translate, and deck separation feature for better interior views. • Point and click operation for most simulation setup • User-selected display for various objects, compartments, and decks. • Damaged surface specification. • User-defined colormaps/legends. • Replay and Compare modes. • Simulation output data extraction for other tools. • Import and export of inputs and outputs. As a tactical tool onboard ships, this work focuses on predicting and visualizing fire spread faster than real-time to assist fire control personnel in firefighting efforts. As a training tool this work allows firefighters to study "what if" scenarios, or as a design tool it provides ship designers the capability to study design alternatives. Different structures with simulation results Compartment temperatures The complete simulation system resulted from collaborative work by Mississippi State University (MSU), the Naval Research Laboratory (NRL), and Hughes Associates, Inc. (HAI). The MSU-developed GUI (Graphical User Interface) provides a runtime environment for setting up simulations, running the Fire and Smoke SIMulator (FSSIM) from HAI, visualizing the results, extracting data for plotting or other analysis, and replaying or comparing simulation results. Fire-Smoke Graphical User Interface Compartment temperatures with custom color legend A wireframe view of the ship showing smoke . Compartments are shown with 100% transparency (totally clear) to opaque as the visibility drops. 2. CAD Processing Database CAD processing Geometry and properties Comparison of two different simulations dxf Once the CAD Processing is complete and the geometry is acceptable, the database contains the necessary information to run simulations. CAD file conditioning Data extraction feature CAD data extraction 3D reconstruction Properties • The FireGUI has been successfully tested on several different geometries. It has been validated against tests on the NRL’s fire research vessel, the ex-USS Shadwell . • Applied to ships and submarines ranging in size from 23 compartments to over 2400 compartments. • Runs faster than realtime on small to medium size geometries (up to two hundred) thus meeting goals for use as a tactical tool onboard ships. For geometries of thousands of compartments, it runs slower than realtime, limiting tactical use but still useful as a design tool where realtime requirements are not critical. The geometry information is extracted, conditioned, and reconstructed as a 3D model from a CAD file. The CAD processing has largely been automated with translators written to extract much of the geometry, but it still requires manual intervention in some cases, usually requiring multiple iterations to correct problem areas. Other properties that are not present in the CAD file, such as wall or bulkhead thickness, material, and composition, compartment names and numbers, and compartment usetype (category) are provided via a spreadsheet or property file. Input (Simulation Setup) Output (Simulation Results) FSSIM (Third-party Fire Model) By Hughes Associates, Inc. FSSIM 5. Works in Progress • FSSIM is a network model where each compartment is a node and surfaces, doors, hatches are examples of node connections. FSSIM takes a text file as input and outputs the data as a text file. • FSSIM Features: • Fire spread via heat transfer, boundary cooling or compartment specific criteria. • Fire detection via heat and smoke. • One-dimensional flow model including friction losses and temperature-dependent specific heat. • Bidirectional flow through horizontal (hatches) and vertical (doors) flow connections. • Oxygen- and fuel-limited combustion. • Combustion product species tracking. • Using the GUI for simulation and visualization of other models, such as for adaptive and reconfigurable electric systems, is • being explored. • Future Work: • To add capability to allow human intervention during a simulation • To allow the user to select the compartment usetype (and thus fuel loading). Accreditation The Department of the Navy presented a certificate to Mississippi State University's Center for Advanced Vehicular Systems recognizing successful completion of verification, validation, and accreditation of this software model in March 2007. This research is currently supported by the Naval Research Laboratory under Contract N00173-07-2-C008. Contact Information: haupt@cavs.msstat.edu, henley@cavs.msstate.edu, and bhargavi@cavs.msstate.edu.