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Author Topic: How to know whether the fire has been extinguished?  (Read 4099 times)

tricia

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How to know whether the fire has been extinguished?
« on: March 19, 2015, 08:26:18 pm »

I had simulated sprinkler right above a 200kW/m2 burner with specified extinguishing coefficient. I am able to check the sprinkler graph that the sprinkler had activated after 74 seconds. The sprinkler is able to lower down the room temperature but it does not cause any changes to the HRR. How do i know whether the fire had been extinguished? Is there any graph which shows that? The simulation video is not able to show that the fire has been extinguished?
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Dave McGill

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Re: How to know whether the fire has been extinguished?
« Reply #1 on: March 19, 2015, 11:48:23 pm »

Hi Tricia,

There should be a decline in the HRR when you graph the casename_hrr.csv file. Try using a larger value for E_COEFFICIENT. Can you attach your .psm file?

Dave
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Dave McGill
firemodel.ca

tricia

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Re: How to know whether the fire has been extinguished?
« Reply #2 on: March 20, 2015, 12:21:41 am »

Hi Dave, Thanks for your help. Attached the file.

For this trial test, I had created a simple models with 3 sprinklers. It appears that the temperature of the sprinklers will still increase after it have been activated which seems weird.
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Dave McGill

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Re: How to know whether the fire has been extinguished?
« Reply #3 on: March 20, 2015, 06:17:11 am »

Hi Tricia,

I think you should step back and cover some of the basics.
  • the cells in your model should be cubes, or close to it.
  • the cells should be much smaller, on the order of 0.1 m a side
  • the current domain is a sealed box, there should be OPEN vents to provide makeup air and venting of the smoke

Run the attached file, which is one of the examples supplied with the installation of FDS. It demonstrates extinguishment of a burner by a sprinkler.

Dave
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Dave McGill
firemodel.ca

tricia

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Re: How to know whether the fire has been extinguished?
« Reply #4 on: March 21, 2015, 06:46:36 pm »

Thanks for the advice. This is my 1st attempt to try out pyrosim. Will reduce the mesh size and create vent. :)
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wilsonobre

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Re: How to know whether the fire has been extinguished?
« Reply #5 on: March 25, 2015, 07:39:24 am »

Hi!
Mr. McGill have you ever done any simulation, using the (Argonite IG-55) in Pyrosim! Soon i'll need to do this, in a study that i'm doing in a DataCenter, so,  it will be useful if i had some examples to follow.
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Dave McGill

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Re: How to know whether the fire has been extinguished?
« Reply #6 on: March 25, 2015, 05:19:51 pm »

Wilson,

No, I haven't. It's an inerting agent, so you should be able to model it in PyroSim.

Dave
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Dave McGill
firemodel.ca

wilsonobre

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Re: How to know whether the fire has been extinguished?
« Reply #7 on: March 25, 2015, 06:30:07 pm »

Great! I'm not able to do this! But thanks for your advice!
I hope somebody else  help me
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