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Droplet Breakup in a T-Junction Tutorial
Posted 13.12.2010, 13:49 GMT-5 Fluid & Heat, Microfluidics, Studies & Solvers Version 4.0a 1 Reply
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I want to do some modeling of droplets using version 4.0a and decided to start by doing the "Droplet Breakup in a T-Junction" tutorial. The tutorial was made for version 3.5a, before the "Transient Initialization" study step was introduced, and so the initialization of the level set function is done using a saved solution from version 3.5. I would like to be able to run this tutorial using the Transient Initialization step instead of the saved solution, as a way of teaching myself how to use this new feature.
When I download the .mph file and run it on my machine without making any changes, it runs fine and finishes in about 15 hours. I then made the following changes to use the Transient Initialization step:
-Added a new study, using the "Transient with Initialization" study type.
-Deleted the old study.
-In "Step1: Transient Initialization" I set the time to 6e-4 seconds (as suggested in the tutorial).
-In "Step2: Time Dependent" I set the time to range(0,0.005,0.08) (same as before).
-Selected "Compute" for the new study.
After about 20 hours the program is still working on time point 0.00002 and spits out the error "Error: Failed to find time step so that given tolerances are satisfied".
It seems to me like using the new "Transient with Initialization" study type should be quite straight-forward, so I must be missing something simple. I've attached my model to this message. Any help is greatly appreciated!
Cheers,
Adam
When I download the .mph file and run it on my machine without making any changes, it runs fine and finishes in about 15 hours. I then made the following changes to use the Transient Initialization step:
-Added a new study, using the "Transient with Initialization" study type.
-Deleted the old study.
-In "Step1: Transient Initialization" I set the time to 6e-4 seconds (as suggested in the tutorial).
-In "Step2: Time Dependent" I set the time to range(0,0.005,0.08) (same as before).
-Selected "Compute" for the new study.
After about 20 hours the program is still working on time point 0.00002 and spits out the error "Error: Failed to find time step so that given tolerances are satisfied".
It seems to me like using the new "Transient with Initialization" study type should be quite straight-forward, so I must be missing something simple. I've attached my model to this message. Any help is greatly appreciated!
Cheers,
Adam
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1 Reply Last Post 11.01.2011, 00:24 GMT-5
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Posted:
1 decade ago
I found the problem with my model. The default solver that is created with the new study is not suitable for this simulation. By right-clicking "Solver Configurations" and clicking "Show Default Solver", the nodes and settings for this solver can be adjusted to match those that were used by the old study. When this is done, the simulation runs smoothly to completion.