Exploitable results Tools for Fire Simulation in Underground - OSIS This 1D code is a simplified approach suitable for modeling underground networks and simulate the effects of a fire on the whole ventilation system, what CFD codes can't do due to the amount of resources they require. The objectives are the following: - Assess smoke temperature and follow the spread of smoke in the galleries downstream to the fire seat - Compute air flow distribution in the network taking into account thermal effects on pressure losses and fan thrust General design is based on the VENTITEC Program developed by TEC INGENIERIE and the additional fire model called FEUTEC. Ventitec is a ventilation program that computes pressure and air flow distribution in a network when temperature distribution is given. The fire model Feutec has to compute the temperature field given fire characteristics and flow distribution. The two codes run alternatively at each time step. The software can work in standalone mode or in conjunction with the 3D model developed by WS ATKINS. In standalone mode, a simplified model of fire is used to determine initial characteristics of smoke fronts. It assumes that the heat release rate increases linearly with time and that smoke temperature follows a predefined curve. At each time step, a new front of smoke is emitted. Its characteristics are either assessed by the simplified fire model or given by the CFD code STAR CD in case of coupling of the 2 codes. The fire model then manages fronts evolution in the galleries, taking into account heat exchange with walls. Virtual reality code with quantitative display of visibility through smoke Provide an overview of the result which gives the reader an immediate impression of the nature of the result, its relevance and its potential; Briefly describe the current status/applications of the result (if appropriate) with non confidential information on entities potentially involved. The Superscape Virtual Reality (VR) package has been used to create a user-friendly and cost-effective way of displaying data from experimental tests and from three-dimensional computational fluid dynamics (CFD) models. It facilitates the interpretation of test results and computed results by non-specialist users such as metro operators or safety organisations. The VR facility can display the geometry of a tunnel and internal features such as stationary trains, together with 2-dimensional images of test results and computations on cross-sectional planes and surfaces, which can be translucent. Typically the 2-D images are of colour-filled contours of temperature or pressure, with experimental data as superimposed spot values, similarly coloured. An additional powerful feature is the ability to display three-dimensional images of the computed field of smoke density. The VR facility calculates the visual opacity of the smoke and displays quantitatively realistic visibility through smoke clouds, a feature which may be novel. The user may roam within the tunnel world observing the results as they change dynamically over time. This is particularly effective for the smoke representations as visibility decreases over time and the smoke encroaches further into the tunnel. Geometries are read from common CAD file formats and results images from common image file formats. Thus the VR facility is not constrained to use only with the CFD model developed within the OSIS project. First set of portable hot smoke generator 500 KW The OSIS project aims at simulating an underground fire without the drawbacks of classical tools: risks due to real fire, dirtiness of real smoke, no-repeatability of real fires. Portable generators have been within the OSIS project which can be easily adapted for instance in concourse, mines, and road tunnels. Two generators using forced ventilation were built for a total of 500 kW. The on-site tools form a unique mean to test installation before they are opened, to check the design and the tuning of the equipment. In contrast with tests using real fires, the temperature and electrical power of OSIS tools have been chosen not to damage usual equipment in tunnel, which have been confirmed by the various tests that have already been carried out. 3D Simulation and calculation code for fire and smoke spread in tunnels etc. The Computational Fluid Dynamics (CFD) model produced represents well the spread of fire and smoke in tunnels or underground spaces such as stations. Individual tunnel designs and fire conditions are simulated; the computed results help in understanding the development of dangerous heat and smoke conditions within tunnels when fires occur. Computer simulation allows scenarios to be investigated where experimental study would be too dangerous, destructive or costly. It also aids comparison between alternative designs of tunnel geometry or ventilation system. The model is based on the commercial CFD program STAR-CD. It simulates, in three dimensions and with variation in time, the development of a tunnel fire and smoke transport within the tunnel air flow. Technical work, tailored to this application, includes the identification and application of the most appropriate up-to-date methods of modelling: combustion; anisotropic turbulence; smoke characterisation; radiative heat exchange between smoke and surfaces; and convective heat transfer at surfaces. The model has been validated by simulating results of experimental tests performed within the OSIS project and elsewhere. An automatic link has been developed between the 3D CFD model and the 1D network model so that the fire effects and the air flows within a whole tunnel system interact. Searching for OpenAIRE data... There was an error trying to search data from OpenAIRE No results available
