A Smoke Detector Algorithm for Large Eddy Simulation Modeling
نویسندگان
چکیده
This study chronicles the development and integration of a smoke detector activation algorithm that describes the response time of a smoke detector into a Large Eddy Simulation (LES) fire model. Although the activation algorithm could be used with any CFD smoke movement model, the results here address specifically its application to the Fire Dynamics Simulator (FDS). The fire model predicts the smoke concentration and velocity adjacent to the detector while an algorithm based on characteristic velocity-based lag times describes the transport of smoke into the sensing chamber of the smoke detector. An Underwriters Laboratories Standard 217 fire test, as well as experimental data from two experimental multi-room compartment fires, were used for comparison and validation of the accuracy of the algorithm. A series of benchmark studies in a numerical wind tunnel provided a mechanism to establish the sensitivity of the model to the different input parameters. The algorithm was found to be very accurate in determining detector activation times for both high and low-velocity smoke flows. Additionally, it was found that the algorithm provides more accurate smoke detector activation times than other correlations based on optical density or temperature. The activation algorithm will be included in the next release of FDS (version 5.x).
منابع مشابه
Simulation of Metro Train Fire in an Underground Station of Tehran Metro Line 7
In this research a fire scenario was simulated in one of the stations of the line 7 of Tehran's subway system. The Line 7 is under construction and the ventilation system is under design. Fire was set for a stopping metro train at the platform of the station. A 160 meter length eight-car metro train with the forth wagon on the fire was studied. The heat release rate is based on a quadratic f...
متن کاملLarge-eddy simulation of turbulent flow over an array of wall-mounted cubes submerged in an emulated atmospheric boundary-layer
Turbulent flow over an array of wall-mounted cubic obstacles has been numerically investigated using large-eddy simulation. The simulations have been performed using high-performance computations with local cluster systems. The array of cubes are fully submerged in a simulated deep rough-wall atmospheric boundary-layer with high turbulence intensity characteristics of environmental turbulent fl...
متن کاملLarge eddy simulation of propane combustion in a planar trapped vortex combustor
Propane combustion in a trapped vortex combustor (TVC) is characterized via large eddy simulation coupled with filtered mass density function. A computational algorithm based on high order finite difference (FD) schemes, is employed to solve the Eulerian filtered compressible Navier-Stokes equations. In contrast, a Lagrangian Monte-Carlo solver based on the filtered mass density function is inv...
متن کاملMixed Large-Eddy Simulation Model for Turbulent Flows across Tube Bundles Using Parallel Coupled Multiblock NS Solver
In this study, turbulent flow around a tube bundle in non-orthogonal grid is simulated using the Large Eddy Simulation (LES) technique and parallelization of fully coupled Navier – Stokes (NS) equations. To model the small eddies, the Smagorinsky and a mixed model was used. This model represents the effect of dissipation and the grid-scale and subgrid-scale interactions. The fully coupled NS eq...
متن کامل