ABS fire model

[Heng-sen]

Regarding my ABS fire model:

For the fire source, I used an HRR RAMP curve, but FDS reports ERROR 171 indicating that the amount of carbon in the reaction is insufficient.

My geometry includes 0.1 mm gaps, so I attempted to resolve them by using a 1 mm cubic mesh in order to visualize smoke and heat flow in Smokeview. However, this resulted in ERROR 157 (access violation) during initialization.

I would like to ask experienced users: How should I adjust my model to avoid these errors?
TLPV2.txt

[mcgratta]

I'll take a look.

[mcgratta]

&SPEC ID='ABS' /

should be removed. It contradicts the REAC line because it provides no information about this species. Also, your MESH dimensions are probably far too large for your computer.

[Heng-sen]

thank McGratta, I am going to adjust

[Heng-sen]

other question
Can FDS software limit interpret a mesh size of 0.1 cubic millimeters?
I want to verify 0.1mm crack on tool.

[drjfloyd]

If you have 0.1 mm gaps and you want to actually resolve flow in those gaps, then you are going to need multiple grid cells across the gap. At that resolution you are DNS and this is going to be more reliant on the specific properties of the species present. You have not provided any detailed properties for ABS, and in fact with your current inputs will wind up with non-sensical properties. I think you should take a step back and consider what exactly it is you are trying to do and what is and is not important to consider. You should also carefully review your inputs. For example, your HRRPUA is 113333. This would be multiple kg/s/m2 of burning rate, orders of amgnitude higher than one would expect for ABS plastic.

[Heng-sen]

Dear experts, I have two questions regarding my leakage model:

I defined five leak openings, but Smokeview only shows two gray leak surfaces.
Why are the other leak vents not displayed?

In the soot slice there is no visible leakage flow through the cracks, even though I defined the IOR for each vent.
I am not sure which part of my setup needs to be corrected.

Could you please advise what I might be doing incorrectly?

Thank you.
TLPV4-1.txt

[Heng-sen]

Dear experts~
I revise the model "HVAC_tee_loss_1.fds", why can't conduct this code?

1. set a fuel fire

2. remove "VOLUME_FLOW=0.03"

[HVAC_tee_loss_1.txt](https://github.com/user-attachments/files/24080155/HVAC_tee_loss_1.txt)

3.before remove "VOLUME_FLOW=0.03"

[Heng-sen]

I go to view clearly again.
thank everybody ~

[Heng-sen]

I set up an ABS solid fuel in FDS and defined its bottom surface as an ignition source. The fire is intended to burn until the ABS material is completely consumed, at which point the simulation should naturally terminate.

However, during execution I consistently encounter ERROR(101). I have carefully compared my input file with the FDS User Guide, but I am still unable to identify the source of the error.

I would like to consult an expert on how this configuration should be modified correctly in order to model a pyrolyzing ABS solid with bottom ignition and burnout without triggering ERROR(101).

TLPV4-3.txt

[mcgratta]

I'll take a look.

[drjfloyd]

It is telling you there is a problem with your 6th OBST input. Below is your 6th OBST input and all the valid inputs for OBST. Draw a line connecting each of your inputs with the input given in the table. I have done the first one for you.

[mcgratta]

ERROR(10)) means that one of the parameters on the OBST line is not appropriate. Check the tables in the back of the User's Guide for appropriate parameters for OBST.