Jet Fire

[XinLok]

I google the subject but did not get a clear information what does mean 37.5 kW/m2 contour at a frequency exceeding 10-4 per year !!!
37.5 KW/m2 how much heat can produce and what mean frequency exceeding 10-4 per year?

appreciate any clear information

 

[AlessioC]

Hi @XinLok,

37.5kW/m2 is a typical value for heat radiation (power) per unit area that you can find in literature (see Spouge) and regulations (land use planning). Some consider this value enough to damage structures and equipment. It also depends how long the target is hit by this radiation (10 to 20 minutes are typical values).

• Consider a jetfire source. There are points away from the source (on a selected plane, say z=1m from ground) that are hit by the jetfire radiation. All those points hit by a 37.5kw/m2 value belong to the same "contour".
• If you have multiple sources of possible jetfires, each source contributes to the "probability of having a 37.5 kw/m2 radiation" at a specific location. This probability is expressed in frequency terms (event/year).
• If you calculate the frequency in a specific location (at z=1m or a different height) and it is 10-4 or more, then this point is part of the 37.5kw/m2 @ f>=10-4 contour.
• Calculate the frequency over the full domain (all x, y points at z=1m), all those points with a frequency of 10-4 or more are part of the contour.

Hope this helps. Ask more if required.

Regards