Problems with Meshing of a Rapid Compression Machine
 

Hello Guys,

I´m working on some simulations on a rapid compression machine. picture 1 is the geometry before the compression, picture 2 geometry after...but in my simulation the piston movement ist bigger!
I use Dynamic Mesh with the In-Cylinder-Option (Layering) and a axissymmetric geometry in 2D.



Now i have 2 problems:

The simulation with my normal mesh works, but Tecplot does not show a boundary layer when i have look at the results. But CFD-Post shows a boundary layer. Why?



To avoid this problem i tried to make my mesh finder at the walls (see Attachements). But then i have the problem, that Fluent reports a Negative Volume at the first iteration...I tried some different meshes, but I havent been able to creat a new mesh with a finer boundary layer.
Do you have an idea where my problem is?

Additionally my interfaces are not working fine. I have some divergences in the temperature contour (attachements).

Maybe some of you worked on similar problems and can help me.
Looking forward to it

Thankyou guys

No suggestions?

Hi

I am also making a project in RCM...did the dynamic mesh part .
But stuck in the combustion model ... I trying partially premixed for it
The mixture fuel is inside the cylinder compressed at 30 millisec.
I am able to run the dynamic mesh using the chem kin file for combustion . I got some results...
Issues
1. Pressure not rising during the compression stroke
2. tremperature not rising till 30ms and getting raised at instantly- abrupt
3. No combustion happening after it gets to 700K+ temp


Pl suggest