Simulation Software for Science and Engineering
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This video covers a few of the features available in PyroSim for working with meshes.
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- Creation and modification of a mesh.
- Division of a mesh into multiple meshes.
- Coarsen and refine the resolution of a mesh.
- Open mesh boundaries to ambient conditions outside of the domain.
In this post we use the FDS and the Dynamic Smagorinsky turbulent viscosity model to simulate both a full-scale jet fan experiment and clearing of smoke from a car park garage. The choice of the dynamic Smagorinsky model is based on the discussions in first two posts on modeling jet fans in which dynamic Smagorinsky viscosity enabled a reasonable solution with a relatively coarse mesh (Part 1: Background and Convergence Study and Part 2: An Engineering Approach). The focus will be on the full scale jet fan experiments described by Giesen et al. (2011). Videos showing the calculations can be found here, Jet Fan Videos. Read More »
In the first post on modeling jet fans with FDS, we did a quick background review of downstream flow, including the Potential core and Axisymmetric decay regions for a free circular jet. For flow conditions similar to a commercial jet fan, a mesh size of 12.5 mm was required to obtain reasonably accurate results. Unfortunately, it is not feasible to simulate full scale parking garages with such a fine mesh, even if multiple meshes are used. This post discusses ways it may be possible to use a larger mesh size and still obtain meaningful results (see also Part 1: Background and Convergence Study, Part 3: Applications, and Jet Fan Videos). Read More »
In the latest release of PetraSim we have improved the method we use to extract a fault surface from a set of XYZ points. The challenge is that we know the points are on the surface, but we do not know how the points are connected to define the surface. Read More »
The heat released as a fire burns is distributed to the environment primarily through convection and radiation. In a simulation, you specify the fraction of the fire total heat release rate that should be assigned to radiation. But, when you check the FDS output files you may see a different fractional amount of radiation in the Q_RADI column of data. This post will explain why these values are different, and what you should expect the Q_RADI data to represent. Read More »