FDS+Evac: Problem with STRS

[Antoni Balaguer]

Hi,

I have two FDS files. The first one (Scene.fds) doesn't work (the agents stay around the door to the stairs), and the second one (Scene2.fds) is working, but i can't see the difference between these two files.

Can you help me, please?

[TimoK]

Hi,

You had couple of things in the Scene.fds file. I did not check
the Scene2.fds file.

1) Timo: These should know where they are heading so give the EXIT ER
as
a known door.
&EVAC ID='EVAC ANDANA', PERS_ID='ADULT', NUMBER_INITIAL_PERSONS=100,
MESH_ID='MESH EA', KNOWN_DOOR_NAMES= 'DOOR AR','EXIT ER',
KNOWN_DOOR_PROBS= 1.0, 1.0,
XB=27.920,127.939,51.481,59.488,9.465,9.465, /

2) Timo: You should define an EXIT here also.
&VENT ID='VTEE', SURF_ID='OUTFLOW', EVACUATION=.TRUE., MESH_ID='MESH
EE', COLOR='BLUE',
XB=90.410,90.410,65.600,68.800,24.347,24.447, /
&EXIT ID='EXIT ER', IOR=-1,
XB=90.410,90.410,65.600,68.800,24.347,24.447, /

Now you can give EXIT ER as known door, so the STRS knows to which
floor the agents are heading. In your original version, just the
downstairs door was known, so the agents in the STRS knew just
that door (no EXIT anywhere so the STRS could not figure out
that the agents wanted to go to the second floor). The first
couple of agents were able to enter the STRS, but they turned
around and were trying to get out through the same door that
they entered the stairs. But this was not possible, because
there were plenty of agents at the door trying to go inside
the STRS. So the agents could not find any empty space in
front of the door => "traffic jam".

3) Timo: Now the second landig has z=13.148,13.248, old one were
13.145,13.245,
The new values are exactly 1st landing z +
VERTICAL_LANDING_SEPARATION
XB_CORES was not nice.
&STRS ID='STRS',
XB_LANDINGS(1,:)=127.800,130.000,52.800,58.400,9.415,9.515,
XB_LANDINGS(2,:)=134.490,136.600,52.800,58.400,13.148,13.248,
XB_CORES(1,:)=130.000,134.490,55.379,55.579,8.265,29.200,
MESH_ID='MESH STRS',
VERTICAL_LANDING_SEPARATION=3.733, N_LANDINGS=5,
FAC_V0_UP=0.4, FAC_V0_DOWN=0.75, FAC_V0_HORI=1.0,
XB=127.800,136.600,52.800,58.400,8.465,29.200, /

4) Timo: You are not using EAR anywhere, you have just one door at
the EA level (mesh).
MESH ID='MESH EAR', IJK=300,54,1, EVAC_HUMANS=.FALSE.,
EVACUATION=.TRUE.,
XB=19.800,139.800,44.000,65.600,9.415,9.515, /

Timo: You are not using EAR anywhere, you have just one door at the
EA level (mesh).
VENT ID='VTEAR', SURF_ID='OUTFLOW', EVACUATION=.TRUE., MESH_ID='MESH
EAR', COLOR='BLUE',
XB=127.800,127.800,53.300,54.900,9.415,9.515, /


TimoK

[Antoni Balaguer]

Thanks a lot Timo,

I had the problem with the landing's Z and the situation of the core, as you said. I forgot to export an EXIT from the original fds file, I have only attached you a part of it.

But now I have a similar problem. I want to evacuate agents from a train by defining the known doors of the train known to distribute the agents well. For this I have two meshes at the same Z which abuts on the line of the doors. I've put a DOOR on each door, two VENT on the train mesh (well, one for the aux. mesh for each door), an OBST fot the VENTs and an entry into the platform's mesh. But the agents do not pass the train's doors, it seems to be the same problem of "traffic jam" that you spoke to me but I have also defined the platform exits and their two vents with their meshes.

Before I tried to put the doors on a single mesh but has not worked. 

[TimoK]

Well, you could model the train (one car?) as just one
main evacuation mesh that is having two additional
door flow evacuation meshes (EVAC_HUMANS=.FALSE., which
is the default). Put two DOORs to this main evacuation
mesh (let ID='TrainCarEvac'). The additional meshes
have ID='LeftCarDoor' and ID='RightCarDoor'. Put
DOORs to the TrainCarEvac mesh (XB should belong
to that mesh, and MESH_ID could be given, if the
platform mesh is overlapping or touching the
train car meshes). Put outflow VENTs to both
DOOR positions (same XB) and MESH_ID='TrainCarEvac'.
Put an outflow vent also at LeftCarDoor mesh (use
MESH_ID) and one to the RightCarMesh.

And put two ENTRs at the platform mesh (MESH_ID= for
the platform). MESH_ID is needed if the meshes are
touching and you are placing the DOORs and ENTRs
exactly at the mesh boundary. In this case, you
should tell to which mesh different things belong,
XB is not enough to specify the main evacuation mesh.

And then add to the DOOR lines correct TO_NODEs for
these ENTRs.

Now the main evacuation mesh of the car leads
towards both doors and left mesh to left door
only and right mesh to right door only.

For those EVAC lines that you want to use
left door, put KNOWN_DOOR_NAMES='LeftCarDoor','PlatformExit',
(the PROBS are equal to one by default). And similarly
for the right door agents.

Put an EXIT ID='PlatformExit' to your platform mesh and
put there also the outflow vent.

Now things should be working. Well, add a SLCF output for
the guiding flow fields of evacuation (PBZ= should belong
to the z1 - z2 interval of the evacuation mesh XB).

This should work,
Timo

[Antoni Balaguer]

I finally found the problem. I needed to put the OBSTs for the train door's VENTs at the aux. meshes for each door. I do not understand why this has been necessary here and for all the other VENT not, but at least it works. 

[Antoni Balaguer]

Thanks Timo,

I posted my answer and I had not seen yours. I had already done more or less what you told me. Now it is working. I have another problem but I think it is better to put it in another post.

[TimoK]

Well, you should put OBSTs with EVACUATION=.TRUE., but
no MESH_ID where you have your "ouflow vents".
This way the OBSTs will go to all evacuation meshes,
both to the main evacuation mesh as well as to the
door flow evacuation meshes. VENT should be defined on a
solid OBST, fds5 needs at least one grid cell thick
solid OBST (unless not at the outer boundary of a mesh).

TimoK