Vent over surface error

[FDS_user]

Hello,

I am trying to put a vent over obstruction already having a surface property and getting the following error:

SURF_ID null not found for VENT 1, line number 101

Is it not possible to put vent over obstruction already having surface properties ?

This vent was just a small area to override the some part of surface property.

Any guidance, please!

[dr_jfloyd]

The error is saying that it can't find the SURF assigned to VENT. Check your inputs and make sure you have correctly specified the SURF_ID and that you aren't missing a / somewhere.

[FDS_user]

Hello dr_jfloyd,

Thanks for the answer, that was the reason because of which I was getting the error.

I have another issue. I have applied a vent (with adiabatic properties) over a surface and the surface has some burning properties. The vent does not cover the entire surface but only some part and vent has to get activated after five seconds to stop the area (over which they are) on the surface to burn. But, in the simulation, the area covered by vents does not burn from the start and in fact never burns. Although, vents appear in the simulation right after five seconds.

Can you please suggest anything in this regard?

Thanks!

[Kevin McGrattan]

Try using a thin OBST rather than a VENT.

[FDS_user]

Thanks, I will try that!