Hi

I made a ICE engine simulation with STAR-CCM+.

I prepare different meshes (volume representations) at different positions and cranck angles. Then I compute on one postion for few timesteps , mesh replace the next one. STAR-CCM+ maps the solutions.

I added relevant compressibility terms and momentum sources using field functions and java macros.

It is really easy to set up but it is a bit expensive on the disk because there are a lot of meshes to prepare in advance. So I only did this 2D. I see well the Otto cycle at the end:

http://techni.tachemie.uni-leipzig.d...to_g0_eng.html

The full technology is nearly there. What is missing to the code is the spray injection and moving the vertices between position. It also work with LES.

Has anyone tried moving meshes or engine simulation with STAR-CCM+?

Thanks,

B. Weisser

"--- wer keine Probleme hat, macht sich welche."

Why the hell do you use ccm+ for that. You have all the ICE related features in StarCD.

http://www.adapco-online.com --> ENGINE MODELLING

That is a very odd position to take. I can't imagine CD wanting to keep the old STAR-CD alive for ever ... or adding (m)any new models to it. Last time I was in their office I saw a lot of porting activity: moving models from old STAR-CD to CCM+.

At worst the OP is duplicating effort. At best he is preparing himself for the future.

I don't think adapco-online is maintained any more. It looks pretty much the same as it did in 2002. Although it does conatain a lot of useful info, it's not a good resource for learning new models and modelling techniques.

Hi there,

I'm currently working on a ICE conjugate heat transfer problem and am using a moving mesh within CCM+. The mesh works well from a modified java macro; the problem I have is trying to apply heat flux or temperature values above and below the piston to represent the combustion and oil mist temps. Again, I have written into the macro to modify the field function at each time step to apply the correct values at the correct portions of the liner. For example, above the piston apply a heat flux of 3000, below the piston apply -20, where the piston is in contact with the liner apply 0 so that the heat transfer comes through the rings.

The problem seems to be that CCM+ converts my field function to a nested if statement in assembly code rather than an if...else statement. This messes up the applied values as a nested if statement always returns true (in this case).

Anyone got any ideas how to write field functions to do what I want?

Cheers,

Daryl

Hi Daryl

Try tables in your java macro. They are very powerful and you can control when they update. I guess the only negative is that you have to pay a price for writing stuff to the disk.

This approach has solved my problems with FF feedback.

I hope that this helps.

Steve

Thanks for the advice Steve but I have managed to get the function working after adding some extra sets of brackets to split the function correctly.

[popstar0426]

hi,
Could you give me some instruction about how to move mesh within CCM+?
Is there example in any tutorial?

Best regards!

Originally Posted by Daryl Jones
;175152

Hi there,

I'm currently working on a ICE conjugate heat transfer problem and am using a moving mesh within CCM+. The mesh works well from a modified java macro; the problem I have is trying to apply heat flux or temperature values above and below the piston to represent the combustion and oil mist temps. Again, I have written into the macro to modify the field function at each time step to apply the correct values at the correct portions of the liner. For example, above the piston apply a heat flux of 3000, below the piston apply -20, where the piston is in contact with the liner apply 0 so that the heat transfer comes through the rings.

The problem seems to be that CCM+ converts my field function to a nested if statement in assembly code rather than an if...else statement. This messes up the applied values as a nested if statement always returns true (in this case).

Anyone got any ideas how to write field functions to do what I want?

Cheers,

Daryl

[afiqroslan]

hi
i need some help for meshing value on BWB UAV model that i have designed on CATIA..this model about 0.348 m span, 0.03995 m2
wing-body plan form area, 0.114 m mean chord..i already run this problem but,get wrong result..i think that the mesh i put is totally wrong..need some help please..
tq