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matej June 21, 2007 09:22

polyhedral mesher
 
HI,

I'm trying to use the polyhedral mesher in 4.02 version on a rather complex geometry. I allways end up with a number of concave cells (like ~1000). I have not found yet any way how to get rid of them using different smoothers and approaches. Has anyone have any hints?

thanks

matej

Jörn Beilke June 21, 2007 10:20

Re: polyhedral mesher
 
I usually use the mesher in ccm+ and transfer the mesh to star4. The check sometimes reports concave cells but the geomwrite works without warnings and the calculation runs fine.


Ben June 22, 2007 15:55

Re: polyhedral mesher
 
Yeah use ccm+ its a lot better

matej June 26, 2007 06:36

Re: polyhedral mesher
 
I'll give it a try. thanks

azmir June 29, 2007 03:37

Re: polyhedral mesher
 
So the v4 polyhedral mesher is not same as CCM+ polyhedral mesher? Can CD-Adapco make both mesher equally potent? Or is this a way to make clients suffer unless they buy both star-cd v4 AND ccm+ ?

Peter June 29, 2007 04:23

Re: polyhedral mesher
 
Careful with your comments otherwise adapco's thought police will add there own message about you such as "wow, your so bitter ..." etc.

To answer the first issue. Star-CD and STAR-CCM+ have different release schedules. Also if a developer puts the new version of the poly mesher into STAR-CCM+ there is no guarantee that the same developer will immediately perform the same task on Star-CD. CD-adapco has its development priorities, which in general are only mentioned at user conferences. There are reasons other reasons why this can happen and not just the sinister.

Now for the license change between v2.04 and v2.06 of STAR-CCM+. Up to and including v2.04.xxx, STAR-CCM+ used the Starsuite license exactly as Star-CD does. Form v2.06 onwards this has changed as follows:

The changes are to the parallel use of the code. 2.04 used the HPC licenses first and only took Starsuites if all the HPC licenses were already consumed. For STAR-CCM+ 2.06 this is different because with 2.06 a parallel jobs on "n" processors takes 1 serial license and (n-1) HPC.

Consider the following, you wnat to have 2 serial jobs and 2*2HPC as well. So you license 1 Star-CD parallel * 4 HPC. List price is €30K for the Star-CD parallel + €13K for the 4 HPC. For Star-CCM+ you now need 4 STAR-CCM+ serial (2 for the serial jobs and 1 each for the 2 parallel jobs) + 2 HPC. The price for STAR-CCM+ is €12K per serial and €3,25K per parallel. So we have the following price:

Star-CD price is €30K + 4*€3.25K = €43K

STAR-CCM* price is 4*€12K + 2*€3.25 = €54.5K

STAR-CCM* is more expensive than the higher functionality code Star-CD.

Why did this happen, because Fluent do this, charge money for this license scheme and people pay money for it. If Fluent can do it ...

Regards

Jörn Beilke June 29, 2007 04:28

Re: polyhedral mesher
 
The mesher is nearly the same, but ccm+ is released more frequently. Thats why the latest improvements are in the ccm+ mesher.

Also the gui in ccm+ is a bit more friendly to use. On the other hand proam provides some features for manual manipulation of the mesh which are not found in ccm+.

Dave June 29, 2007 10:09

Re: polyhedral mesher
 
The meshers in STAR-CCM+ and STAR-CD (V4) are exactly the same piece of code, so when an improvement is made, it happens to both codes at the same time.

As has already been said, the only difference is that because STAR-CCM+ is released more often, it will have a more up to date version of the code.

azmir July 2, 2007 00:31

Re: polyhedral mesher
 
Well, that's much better news - that both polymeshers are exact, but one is just a bit slower upgraded!

Thanks for detail info and additional clarifications.

I feel that customers have to play their role once a while although some might do it a tad more often than others. ;)

Suggestion: Star-Cd polymesher could be released or updated more frequently (e.g 4.1.1, 4.1.2, etc).

Addios!

-Azmir-

TG July 2, 2007 08:25

Re: polyhedral mesher
 
The mesher that gets put into any release of STAR-CD is the latest one available when STAR-CD is released. Since the release schedules of STAR-CD and STAR-CCM+ are not identical there are times when the ccm+ mesher is newer than the STAR-CD mesher.

A. Valan Arasu September 28, 2007 01:46

Re: polyhedral mesher
 
Kindly send me the Institutional price for STAR-CD


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