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Author Topic: aggressive smoke developement  (Read 2342 times)

Nitzan Hirsh

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aggressive smoke developement
« on: April 06, 2014, 06:32:12 am »

Hi,
I've seen that in various models the smoke developement was rapid in comparition to NFPA equations  - even with usage of sprinklers / limiting HRR / lowering soot yield.
any ideas about a hidden parameter that controls smoke developement?

My defaults are usually furniture fires, that include -
t-squared HRR, 500-3000 KW, average/fast.
standard polyurethane reaction, with heat of combustion - 17600 kj/kg and soot yield of 0.07.

Thanks!





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Charlie Thornton

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Re: aggressive smoke developement
« Reply #1 on: April 11, 2014, 08:24:03 am »

I'm not familiar with the NFPA model. Is there a test scenario that predicts the smoke layer height over time? How big of a difference are you seeing?
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Dave McGill

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Re: aggressive smoke developement
« Reply #2 on: April 28, 2014, 03:27:33 pm »

Nitzan,

The SFPE Handbook 3rd, Table 3-4.14 lists the soot yields for 4 different flexible polyurethane foams. The average of the values is 0.19 g/g. That is almost 3 x the value you use.

Dave
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Dave McGill
firemodel.ca