Radiative heat flux prediction for large fire using different FDS versions

[Fire-lab KIU]

hi
I am trying to run a large outdoor tank fire to examine radiative heat flux(RHR) on surrounding tanks.
Prior to the main calculation, I just run a simple case to check the heat flux on the target with several FDS version.
The small fire(40cm fire size) showed a similar mean RHR while the large fire(4m fire size) showed different mean RHR  according to the FDS version.
Do I need set additional input parameters for large fire ?

I attached result and input files.

Thanks

Min

 

[fde]

Have you checked the sensitivity of PATH_LENGTH? There was a recent topic in the discussion group and the result was sensitive to the path length. 

[Kevin McGrattan]

Radiative fraction is a function of fire size and other parameters. Typically, a large hydrocarbon fuel fire will decrease in radiative fraction as its smoke shroud absorbs more of the radiation. Very large (10s of m) fires can have radiative fractions as low as 5%, based on far field radiometer measurements. 

[Fire-lab KIU]

Thanks for your comments.

I will try to run with different PATH_LENGTH and RADIATIVE_FRACTION.

2022년 4월 6일 수요일 오후 9시 44분 26초 UTC+9에 Kevin님이 작성: