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Compiling equations taking long (particle tracing)

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I have a model with two Studies:
- Study 1: stationary solver for a flow problem
- Study 2: time-dependent particle tracing, based on the stationary velocity field solution from study 1. (Only the particle trajectories are solved for in this step)

Depending on how I choose the time steps for the particle tracing, COMSOL seems to get stuck 'Compiling equations'.
For instance, if I choose the time steps to be

range(0,1e-3,1)

everything runs fine, but if I choose

range(0,1e-3,10)

and click compute for Study 2, the progress window shows 'Compiling equations' and immediately jumps to 100%, but it gets stuck there.

Does anyone have a clue what might be happening here? The two cases shouldn't make that much of a difference I'd say...

3 Replies Last Post 09.06.2013, 13:46 GMT-4
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Posted: 1 decade ago 27.06.2012, 10:03 GMT-4
i've the same problem...
i'll tell you the workaround if i find one.
i've the same problem... i'll tell you the workaround if i find one.

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Posted: 1 decade ago 28.06.2012, 05:03 GMT-4
i found the problem! :)

you have to delete the particletracing solution in results.
if it's not working also delete the particle tracing physics and set it up new.

worked well for me.
i found the problem! :) you have to delete the particletracing solution in results. if it's not working also delete the particle tracing physics and set it up new. worked well for me.

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Posted: 1 decade ago 09.06.2013, 13:46 GMT-4
what you did for this problem? i have the same problem. Was deleting the particle tracing helped?

I have a model with two Studies:
- Study 1: stationary solver for a flow problem
- Study 2: time-dependent particle tracing, based on the stationary velocity field solution from study 1. (Only the particle trajectories are solved for in this step)

Depending on how I choose the time steps for the particle tracing, COMSOL seems to get stuck 'Compiling equations'.
For instance, if I choose the time steps to be

range(0,1e-3,1)

everything runs fine, but if I choose

range(0,1e-3,10)

and click compute for Study 2, the progress window shows 'Compiling equations' and immediately jumps to 100%, but it gets stuck there.

Does anyone have a clue what might be happening here? The two cases shouldn't make that much of a difference I'd say...


what you did for this problem? i have the same problem. Was deleting the particle tracing helped? [QUOTE] I have a model with two Studies: - Study 1: stationary solver for a flow problem - Study 2: time-dependent particle tracing, based on the stationary velocity field solution from study 1. (Only the particle trajectories are solved for in this step) Depending on how I choose the time steps for the particle tracing, COMSOL seems to get stuck 'Compiling equations'. For instance, if I choose the time steps to be range(0,1e-3,1) everything runs fine, but if I choose range(0,1e-3,10) and click compute for Study 2, the progress window shows 'Compiling equations' and immediately jumps to 100%, but it gets stuck there. Does anyone have a clue what might be happening here? The two cases shouldn't make that much of a difference I'd say... [/QUOTE]

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