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Topics - mdangelmaier

Pages: [1]
PyroSim / Numerical Instability
« on: July 11, 2016, 12:49:06 am »

after roughly 180s of my simulation, FDS stops working and I'm getting a numerical instability error. I have nothing triggered in my simulation.
Anyone has an idea what could be the issue?

PyroSim / Critical Error
« on: July 07, 2016, 04:02:53 am »
Hi guys,

I want to launch a simulation but I always keep ending up with getting a critical error message when starting FDS.

I have tried different solutions but none of them seems to fix the problem. Anyone has an idea?

Apparently something was wrong with my defined materials. Trial and error solved the problem

PyroSim / Pyrolysis v prescribed fire
« on: June 30, 2016, 08:30:25 am »

I want to verify some calculations regarding temperatures which I have done by hand using FDS.

The scenario is more or less a couple of pallets which a cardboard box on top of each pallet. When calculating the temperature by hand
I got a max HRR of 19,4 MW and a burning surface of 18 m² resulting in nearly 500 °C at a certain distance.

Now I was wondering how to properly set up Pyrosim to verify those results. I thought about two options:

1) create on surface of a single pallet with burner and set the reaction to wood. I'm not sure if the cardboard as well as the other pallets
ignite after a while, although they should ignite, right?

2) prescribe the development of the fire using the 19,4 MW and use a Q_RAMP function. I would use several vents which would be enabled one after another to achieve 18m²

What do you guys think?

PyroSim / Sloped Walls
« on: June 23, 2016, 04:09:17 am »

I was wondering, what would be the easiest way to create a sloped wall/ceiling?

Kind Regards

PyroSim / Temperature, HRR not correct?
« on: November 23, 2015, 03:01:51 am »

I have run a simulation and I'm suspicious about the outcome now. What concerns me in particular is the temperature at the
fire source as well as the HRR.

The temperature at the fire source is max. 220° C which is too low in my opinion. Is this a mistake made by pyrosim or is my fire
not 'hot' enough ?

At some point during the simulation the sprinklers are activated but looking at the HRR curve in the results, it appears that the sprinklers
have no effect on the HRR.

Thanks for your help

PyroSim / Reaction fails
« on: November 17, 2015, 08:33:15 am »

I am trying to use polyethylene as fuel for my reaction, but it seems I am never doing it right. There is no smoke visible.
I think I'm doing something wrong with the HRRPUA and HRRPUV in the reaction menu. How do I calculate those variables?

PyroSim / Simulation stopps
« on: November 16, 2015, 01:34:02 am »

my Pyrosim simulation stopps after roughly 100-200s simulation time which is about the 1700th time step.
The simulation is supposed to be running 1800s. There is no error occuring.

Ok I got a step further. So I disabled the sprinkler devices which are activated after 120s. Now the simulation
works fine. Is this a common problem with sprinklers and what could be done to solve it?

Regards Max

PyroSim / Fire Design
« on: November 13, 2015, 02:17:57 am »
I am always designing a fire by putting a burner vent on top of an obstacle e.g. a seat and setting a HRRPUA.

Now I am wondering how one would create a fire if you just have the requirements given. The density of the fire load
maybe around 400 MJ/m² in a 10m² play area inside a wide open hall. My first idea to come up with was to set up a
vent with 10m² and mabe define the Mass Loss Rate. But that would result in a fire the size of 10m² from the beginning
which is not quite accourate I guess.

Any suggestions? Sorry the alle the questioning it is actually kind of difficult when you've never got it explained at least once :-)

PyroSim / Unkown Error
« on: November 10, 2015, 04:54:24 am »

I am recently encountering an unknown error as soon as I want to edit the device SPRK. I want to change the spray model
and herefore I am clicking on the edit button ending in an unknown crash. It happens every time.

Is this a familiar problem and does anyone have a solution to this problem?

Regards Max

PyroSim / SURF ID error
« on: November 06, 2015, 09:24:49 am »

I received an error when I want to run my fds simulation. It says SURF_ID 1 error hence I assume something might be not
properly set up but I am not sure what it is since I copied it from an already working simulation.

RGB = 0.66,0.66,0.66
C_P = 0.88
DENSITY = 2100
KS = 1.1
DELTA = 0.7/

Probably it's something quite apparent which doesn't occur to me.


PyroSim / Plattform Screen Doors
« on: October 20, 2015, 07:20:16 am »

I am currently working on a project in which I want to simulate Plattform Screen Doors in a subway station.
Therefore I want to the doors to be open at the beginning of the simulation and close automatically after
2 minutes.

My question is whether this is possible to do with Pyrosim or not. If it's possible (which I hope) how would
I do it?

Thanks in advance!


PyroSim / Reactions for several liquids / substances
« on: June 06, 2015, 11:43:26 am »
Hi guys,

I just wondere if is there a PyroSim library which includes liquid reactions such as gasoline or diesel?


PyroSim / No smoke occurs
« on: May 05, 2015, 09:36:35 am »
Hi guys,

a couple of weeks ago I had the same problem with my model. Somehow I fixed it, but on my current model it occurs again, except this time I can not get it fixed :)

When I am running my simulation, no smoke is occuring while using SmokeView. I tried different reactions but these have no effect on the smoke not showing up.

I attached my .psm file, probably it is just a minor error which I do not see at the moment.


PyroSim / No reaction occuring in smokeview
« on: April 02, 2015, 09:35:27 am »

we are currently working on a project using PyroSim.

When I start smokeview no reaction, smoke or temperature is shown hence I guess no reaction is happening.

I defined a fire source using a vent on top of a component and used the polyurethane standard reaction. Do I somehow have
to link the vent to the reaction component?

Thanks for the help.


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