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Topics - Zugin

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PyroSim / Invisible wall between meshes?
« on: May 11, 2020, 05:38:21 am »
So i have such problem:

I have really huge open space in which I want to simulate smoke spread. In huge shortcut I devided model like this:
1) everywhere near the fire I have mesh 0,4x0,4x0,4, meshes with such dimensions ends on smoke curtain.
2) after smoke curtain I have everywhere 0,8x0,8x0,8.

Here is the problem. The fire spread normally for 100-120 secs. After that the velocities are spreading normally only in my 0,4x0,4x0,4 meshes. On 0,8x0,8x0,8 meshes it looks like the velocities are nearly 0m/s. The smoke on Y visibility slice looks like there is an invisible wall (?)(attached 2 screenshots). After opening my smoke vents (I am opening it by "controler" and deactivation obstacles) and aeration holes it looks like this "invisible wall" disappears ?

Really, I tried almost everything. Changed the meshes dimensions, changed the place, dimensions and HRRPUA of burner vent.

I attached pictures of situation before the ventilation starts and 20 s after smoke ventilation system starts work.

Can you help me? Maybe show me where I am making mistake?

PyroSim / flashover fire
« on: April 06, 2017, 03:00:06 am »

I'm a student, who is trying to make model in which fire in smokeview can "move" from for example table and make that bed will light up because of pyrolisis/temperature.

I already set up :
- materials (wood and foam in which i edited reactions and let the fire spreading up through the layers of furniture) i set up also heat of reaction (endothermic) and heat of combustion.
- reaction ( i didn't limit the fire, and didn't set up anything in "advanced" i set up rest - fuel and "according to attribute of material")
- Maybe i made mistake somewhere in surfaces, but i can't find it out.

Here are my questions
1. What is going on with pyrolisis range ? i can't get this
2. How about radiative fraction ? is that thing that let me spreading my fire?
3. What can i do to let my fire "spread" on rest furniture in the room?
4. What else information do you need to help me with this problem? I saw NEST's fds examples, but when i'm trying to open it, I have a question: on which fds 4 5 or 6 i want to run it. No metter which one i choose, something will be missing for example reaction. I don't know how to handle it, because i heard that these examples may help me with understanding this.

Maybe you could tell me what I'm supposed to do, to have experimental fire which will spread and "jump" from furniture to furniture, and make cell-by-cell burn into elements of interior design.

Best regards,



Do I need to set up in which temperature for example wood should light up? If yes, where i can find those informations?

These are information from FDS save- way :

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