Acusolve - Exhaust Manifold Simulation


Hello Forum,
I am a student and am learning how to use acusolve, I would like to know how to make a simulation of an exhaust manifold. I want to know what I have to define so I can have inlet conditions that change by time, do I only need to modify boundary conditions?
Thanks,


You would need
Global
- Auto Solution Strategy- Transient.
- Multiplier Function
Model-
- Inflow boundary condition with a multiplier function. This multiplier function defined above
Do you have a tutorial on how to use the multiplier function?
This might help you to get started.


This might help you to get started.
Now I get this error message as I run Acusolve, any tip?


what would be a more realistic time step? (I can not upload the file, the forum says I am not permitted to upload that kind of file)
Thanks,


Time step 0.1 sec might be a good starting point.
Please upload .inp and .Log file. If necessary, rename the extension to .txt.
Here it is.


It does not helped the 0.1 seconds, I still have the same error
The problem was the Time was supposed to be Piecewise Linear.
With that one change it runs. Input file attached.
BTW, you would need to makes considerable changes to get useful results. Mesh is too coarse to get any accurate results. Also Nodal Output would be have to be changed to lesser value (e.g. 1 or 10), instead of current default 1000.
If you have not attended any training, I would recommend to visit an AcuSolve training at the nearest Altair location.


The problem was the Time was supposed to be Piecewise Linear.
With that one change it runs. Input file attached.
BTW, you would need to makes considerable changes to get useful results. Mesh is too coarse to get any accurate results. Also Nodal Output would be have to be changed to lesser value (e.g. 1 or 10), instead of current default 1000.
If you have not attended any training, I would recommend to visit an AcuSolve training at the nearest Altair location.
Thanks, the Time should be change only in the multiplier function or where else did you put Piecewise Linear
Please compare the .INP file I uploaded with the one you uploaded /emoticons/default_wink.png' alt=';)' srcset='/emoticons/wink@2x.png 2x' width='20' height='20'>
# +----------------------------------------------------------------------+
# | Multiplier Function |
# +----------------------------------------------------------------------+
MULTIPLIER_FUNCTION( 'time' ) {
type = piecewise_linear
curve_fit_values = { 0.0, 900.0;
5.0, 900.0;
7.5, 0.0;
10.0, 0.0;
12.5, 900.0; }
curve_fit_variable = time
evaluation = once_per_time_step
filter = none
}
You would need
Global
- Auto Solution Strategy- Transient.
- Multiplier Function
Model-
- Inflow boundary condition with a multiplier function. This multiplier function defined above