HVAC not connected

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José Felipe Pérez Segovia

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Aug 22, 2023, 10:48:20 AM8/22/23
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Hello!

I am running a case with HVAC and when  I visualize the results in the pyrosim viewer I found this (see fig1).

The black line is a duct and the node position is far away from the expected position.
I include the .fds file. I checked the setup and it seems solid to me. I think that this is a visualization problem. has anyone had this issue before?

Thanks!
test.fds
fig1.png

dr_jfloyd

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Aug 22, 2023, 11:15:03 AM8/22/23
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Issues with Pyrosim should be reported to Thunderhead Engineering technical support.

José Felipe Pérez Segovia

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Aug 22, 2023, 11:16:50 AM8/22/23
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Thanks for this, I only would like to have confirmation the I am not doing something weird in the .fds file.

dr_jfloyd

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Aug 22, 2023, 11:27:26 AM8/22/23
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Your domain is (7.5,32.4,2.0) to (27.3,35.2,4.6).  The two NODEs with XYZ are (16.4,34.5,3.6) and (17.6,33.1,.6). Both are inside the domain.

José Felipe Pérez Segovia

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Aug 22, 2023, 11:37:40 AM8/22/23
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Thank for this, 

The nodes that you mentioned are in the center of the obstruction and they are fine. The node that is not located as it should be is associated with a vent.

&VENT ID='Vent101', SURF_ID='HVAC', XB=8.8,8.8,34.0,35.0,3.4,3.8/ 

&HVAC ID='Node106', TYPE_ID='NODE', DUCT_ID='Duct02', VENT_ID='Vent101', LOSS=1.0,1.0/

I know that everything is inside the domain. That is the point of my question. 

dr_jfloyd

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Aug 22, 2023, 11:49:17 AM8/22/23
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This is a Pyrosim issue.

José Felipe Pérez Segovia

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Aug 22, 2023, 3:10:16 PM8/22/23
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ok, thanks.

fde

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Aug 22, 2023, 5:18:20 PM8/22/23
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I had submitted a similar case to Pyrosim support. They were going to contact FDS developers. You can check the following and see if this work around solves your issue temporarily:
Open smv file with a text editor. Search for a large number. In my case I found a number in the order of E+11. If you change this into a smaller value, the issue is resolved. Search HVAC NODES in the smv file:


HVAC

 NODES

 2

 1 % Inlet08 % Unassigned % 1

 -0.100000E+11-0.100000E+11 0.800000E+00 % NO FILTER % Inlet08                                                     

 2 % Outlet08 % Unassigned % 1

 -0.100000E+11-0.100000E+11 0.800000E+00 % NO FILTER % Outlet08 

dr_jfloyd

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Aug 22, 2023, 6:07:39 PM8/22/23
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fde, did you define XYZ(1) and XYZ(2) in your input? It looks like that was not the case in the output you have. For the input file in this thread  the outputs are not E11 since all the nodes in the input file had fully defined XYZ values (either explicitly on the NODE input or because they are attached to a VENT with an XB):

HVAC
 NODES
 4
 1 % Node106 % Unassigned % 1
  0.880000E+01 0.345000E+02 0.360000E+01 % NO FILTER % Vent101                                                    
 2 % Node102 % Unassigned % 1
  0.164000E+02 0.345000E+02 0.360000E+01 % NO FILTER % null                                                        
 3 % Node104 % Unassigned % 1
  0.176000E+02 0.331000E+02 0.360000E+01 % NO FILTER % null                                                        
 4 % Node105 % Unassigned % 1
  0.256000E+02 0.331000E+02 0.360000E+01 % NO FILTER % Vent104                                                    
 DUCTS

José Felipe Pérez Segovia

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Aug 23, 2023, 3:07:34 AM8/23/23
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Hello, 

Thanks for the help fde.
 




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fde

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Aug 23, 2023, 3:19:12 AM8/23/23
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dr_jfloyd,  no I do not think I defined XYZ. My input file looked like this:

&VENT ID='Inlet08', SURF_ID='HVAC', XB=92.0,92.0,82.6,83.2,4.0,4.6/
&VENT ID='Outlet08', SURF_ID='HVAC', XB=93.6,93.6,82.6,83.2,4.0,4.6/

&HVAC ID='Duct17', TYPE_ID='DUCT', DIAMETER=0.3048, FAN_ID='Impulse_50N', NODE_ID='Inlet08','Outlet08', ROUGHNESS=1.0E-3, LENGTH=1.6, DEVC_ID='TIMER->OUT'/
&HVAC ID='Inlet08', TYPE_ID='NODE', DUCT_ID='Duct17', VENT_ID='Inlet08'/
&HVAC ID='Outlet08', TYPE_ID='NODE', DUCT_ID='Duct17', VENT_ID='Outlet08'/
&HVAC ID='Impulse_50N', TYPE_ID='FAN', TAU_FAN=-5.0, VOLUME_FLOW=3.87298/


Nevertheless I do not wish to disturb the subject in the thread. 

dr_jfloyd

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Aug 23, 2023, 7:02:03 AM8/23/23
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fde,

I think your issue is related to this thread. Only in your case it may be an FDS and not a Pyrosim issue. For a NODE attached to a VENT, the smv file for FDS 6.8 should use the center of the XB for the VENT as the NODE XYZ. For the inputs you gave, the first node should have been something like:

1 % Inlet08 % Unassigned %
 0.92000E+02 0.82900E+02 0.43000E+01 % NO FILTER % Inlet08 

The "Unassigned" means no NEWTORK_ID was defined for the NODE (in Smokeview you can view all HVAC components or just components assigned to specific networks). The "NO FILTER" means there is no FILTER_ID defined for the NODE. 

If you have an input file where you have specified XYZ values for a NODE either by using XYZ or VENT_ID and you are not seeing the correct XYZ values in the smv file, please open an issue with the inputs so we can figure out why it isn't working in your case.

fde

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Aug 23, 2023, 8:27:14 AM8/23/23
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Thank you very much. I will open an issue for the file I excerpted above.  
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