Discussion Forum

Hello Jean-Francois,

In version 4.1 you can define a curve by its parametrization, for instance a corkscrew can be parametrized by

x=cos(s)
y=sin(s)
z=s

where s is the parameter.
In 2D you can draw a boundary with a cosine shape by

x=s
y=cos(s)

etc.

In addition you can sweep a face drawn in a workplane along a 3D curve. Combining the two features, you can generate objects like the one shown in the attached screen shot, where a hexagonal face is swept along a spiral-like parametric curve.

another Jean-Francois

Thanks
One more question tough...

Will it be possible , say in 2d to do geometric parametric sweep with a one parameter family of parametric curve? say x=s and y= cos(p*s) [ stupid example but formally correct]
That will be awesome for I am struggling with matlab script to do exactely that at the moment...

Thanks for your answer anyway
,
JF

wonder how many JF use comsol...lol

ps this question is practically important for me for if it is yes I will stop working on my scripte waiting for 4.1...

Yes, you can parametrize a parametric curve and run a parametric sweep.
See screen shot, with the geometry showing p=3.
JF

This is a KOOL feature..
and if the parameter can be the time .. it is going to be better than "ale" for a lot of problems...
guess I am going to wait this release before finishing my scripting work

just wonder how you manage efficient remeshing and soliution transition to move from one curve to the pther [ I have been doing it a little bit in one very special case through matlab scripting and long list of bezier lines..and so I appreciate that this is not easy..

. so kudos to you guy, specially if it really works the way I expext it to work :-)

JF

No, the parameter cannot be time. You still need to use ALE for that.
JF

Hi I was anticipating that. answer .:-)
[but just half joking tough]
because with the explicit time scheme capability that you just implemented, time becomes really just another parameters but I understand that you will be reluctant to deploy a feature that will not be fully implicit in line with the rest of your product.

Thanks for these info anyway...

JF

Hi,

does anybody know when the version 4.1 will be released (in Europe)?


Best regards

because with the explicit time scheme capability that you just implemented, time becomes really just another parameters but I understand that you will be reluctant to deploy a feature that will not be fully implicit in line with the rest of your product.

Can you elaborate more on this? Is it already in 4.0 or will it be in 4.1?


Danial


--
Comsol 4.0a
Ubuntu 10.04.1

Explicit time scheme is already there in 4.0
BUT with a twist
you need to code specifically ..which is strange and demand that you maintain 2 versions of your code [one for normal "implicit" and one for the explicit scheme.. if you also want to do implicit..

You will find it in the doc easily

i sent a suggestion to comsol a while ago suggesting that the choice implicit vs explicit should me made "one click" option
not sure if I will be followed because the "problem" with explicit is that you always get a "solution"... and then youw ill get tons of question on this forum such as comsol dont work " my solution look weird"...

but it will be very usefull at least to me..
not sure if that was what you were asking for ... just my 2 cts...
JF