Performances of inlet manifold (CFD analysis)

[MadMatt]

Before I introduce you the work I have done, I would like to know if some poeple here are familiar with CFDesign 2011, so they could test 1 CAD model I have already tested but for which I haven't got accurate results compared to the experimental test. If so then I will present my work which may lead to a discussion on the shape of plenum chambers and intake manifolds in general if motivated persons are willing to contribute !

[flynfrog]

I have not used the software you are talking about but I know enough to make colorful pictures in a few cdf programs. Are you siming in steady state?

[flyboy2160]

are you running a viscous-flow solution?

[MadMatt]

I have applied a pressure on the throttle body side and I want to get the flow rate of 1 channel after another (like you have to test). The values are realistic but the difference between the channels doesn't match the experimental test conducted on a flow bench !

I will have to check how I have conducted the test with CFD because at the moment I do not remember all the parameters (it was months ago) But here are 2 pictures for you :

1) This is the standard part, including the plenum, the intake and the throttle body


2) This is the standard part but with a "Swedish" type plenum


I have seen improvement with the swedish plenum of course, but the values of the different cylinders are too close to be true (especially from the standard part which I was able to test). So this is why I hope that a member could test the 1st part and tells me what results he gets so I can hopefully see where I made a mistake. I've tried different configuration parameters as I remember, including variation of the boundary layers (from 2 to 5) but without dramatic changes.