Visualizing smoke

[Customer]

How do I visualize the smoke from a fire in my VentSim model? 

[Martin Griffith]

If you want to visualize smoke in your Ventsim model, the quickest, easiest way is to place a contaminant in the airway containing the smoke source and then run a Contaminant Simulation. This will give you the distribution of the contaminant throughout the mine, assuming a constant supply of contaminant. To make your contaminant model match a real-life scenario, you can also run a Dynamic Contaminant Simulation and adjust the release rate of the contaminant in the Dynamic Behaviour box of the Contaminant tab of the Edit form. You can set a release period, delay the release, or add a linear or logarithmic decay to the contaminant release rate. 

If you are modelling a fire using VentFIRE, then the released smoke is dependent on the configuration of your fire. A fire will release a range of gases; what we refer to as smoke in this context is the visual component of the releases gases, ie the visibility-reducing component. Some combustion fuels, when burning, will produce lots of visible soot (such as rubber) while others will produce less (such as propane). 

For VentFIRE simulations, we refer to the visibility-reducing smoke produced by a fire, as Soot. Each combustion fuel that you burn in a Fire Event has an associated yield of soot per unit of fuel burnt. You can find the soot yield in Settings -> Presets -> Combustion Fuels.

The soot created by the fire can be visualized by selecting the Soot property, which can be found among the Gas properties. Soot will also be among the plotting options for any Dynamic Monitors you have set up in airways containing soot.

Furthermore, there is a property Contaminants -> Visibility, which gives the visibility length in the airway; the visibility is calculated as a function of soot.