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 1 
 on: November 14, 2018, 01:53:43 am 
Started by JB - Last post by Timo
Hi,

you can create a new activation control under the 'Controls' tab. Just select 'Deactivate' at '30 s'.
Then you can link the obstruction (e. g. a wall) with that activation control via 'Obstruction Properties'.

Cheers

 2 
 on: November 13, 2018, 09:58:16 pm 
Started by JB - Last post by JB
hello, I am comparing real model experiment and pyrosim simulation, and I need a wall to be disappeared in the middle of the simulation-that's because we put away one wall because combustion stopped due to lack of oxygen.

Is there any way to make one object disappeared of unactivated in the middle of the simulation, like 30 sec after?

Please let me know if you have any idea:)

 3 
 on: November 12, 2018, 06:19:25 am 
Started by kapilgupta - Last post by Oliviageorge098
I can't paste a link here, but I search there the same thing and they give me 4 results. Have you searched there in the search bar? You can easily find there I dont know why you are not finding, go and try again.

 4 
 on: November 12, 2018, 06:11:13 am 
Started by llammar - Last post by Oliviageorge098
Such a great info

 5 
 on: November 12, 2018, 04:54:37 am 
Started by Gary - Last post by Timo
Hi Gary,

from what I gather you are interested in the radiation received at a certain point in space (target) at a certain distance from the heat source (emitter). 'Radiation Loss' is the wrong parameter for this. I suggest you set up a device (or an array of multiple devices) along the egress route, measuring the parameter 'Radiative heat flux gas'. The results will be plotted in a spreadsheet file.

The tenability limit of 2,5 kW/m² is commonly referenced in literature and should be reasonable, especially for short duration of exposure.

In regards to hand calculation your formula doesn't look right. The radiation received by a target is depending (among other things such as temperature and emissivity of the heat source) by the distance and angle from the source, typically described by a configuration factor. You may want to refer to literature on this topic, e. g. D. Drysdale, An Introduction to Fire Dynamics

Good luck

 6 
 on: November 11, 2018, 11:07:40 pm 
Started by a_elgazar - Last post by a_elgazar
please  in attched  FDS file  i  try to  make  simulat for smoke  fan  many  time  with out  positive result 

if  any  help   for  explore  problem 

thanks

 7 
 on: November 11, 2018, 12:38:08 pm 
Started by Gary - Last post by Gary
I have a scenario where I am trying to measure the radiative heat transfer and subsequent tenability within an open plan apartment and the relationship between cooking facilities and the means of escape.

I have inserted a slice file within Pyrosim which measures radiation loss however the units at Kw/m3 and not Kw/m2 therefore perhaps I am measuring the wrong parameter.

I am considering using a hand calculation where:

q=Stefan-boltzman constant x T(absolute temp in Kelvin) x A (area of emitting body)

Would the forum agree this is the correct formula or is there another formula to prove that the radiative heat does not exceed 2.5Kw/m2?

If anyone has used this formula, is the temperature measured at the source of at the various points along the MoE?

 8 
 on: November 06, 2018, 05:31:34 pm 
Started by jmurch - Last post by jmurch
When building the pathfinder geometry, everything except occupants show up as solid black.
Is this a graphic card issue or a licencing issue? or something else.

Nothing i try brings the colours back.

 9 
 on: October 27, 2018, 05:07:00 pm 
Started by fidome787 - Last post by fidome787
I was reading the comparison between the time taken for the different modes in PATHFINDER. Almost, everyone seemed to have got more time on the SFPE mode. However, weirdly enough I have the time for evacuation in SFPE mode lesser when compared to the time for evacuation in STEERING mode. Am I doing something wrong?

 10 
 on: October 25, 2018, 08:26:47 am 
Started by xyz_13 - Last post by Timo
Hi,

if you double-click on the temperature bar it opens the FDS preferences. There you can change the display settings including data range (use "Custom" in the dropdown menu).

Regards,
Timo

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