Once again, I didn't really know exactly where to put this as it overlaps different areas/aspects of computing, but I'm gonna dump it here and if the mods/admins want to move it to somewhere else where they think it's more appropriate, they can always do so.
Anyways - so I think that SOME of you here might know that I'm a mechanical engineer. Some might also know that my day job is in body and chassis systems. And a select few (from years past) might know that I've been working on trying to simulate an internal combustion engine for quite some time now (spark ignition to be more specific).
It looks like that the combustion is finally working (sort of).
So, a little background - the "can" that you see is the space that represents where the air/fuel mixture will go. It IS based on actual geometry from an actual engine, so unlike the simple representations that you see/get, this is the real deal. The original engine was a V8, stroke of 86.64 mm, bore of 91.90 mm.
I used to start the simulation/analysis from top dead center (TDC) because meshing was a PITA, but now; I've thought about the meshing strategy again, and I'm starting from bottom dead center (BDC).
Anyways, enough of all the technical stuff. Here's the video:
http://www.youtube.com/watch?v=AE28BCYqJSo
This shows the flame propagating through the entire combustion chamber.
http://www.youtube.com/watch?v=zj18Az6SVtY
This is a contour plot of 2,2,4-trimethylpentane mass fraction (through the middle of the combustion chamber).
http://www.youtube.com/watch?v=pSSfD8KUb0w
This is a contour plot of CO2 mass fraction (through the middle of the combustion chamber).
http://www.youtube.com/watch?v=R5ocbj-HfIk
This is a contour plot of absolute pressure (through the middle of the combustion chamber).
http://www.youtube.com/watch?v=wcDMMSV5JdE
This is a contour plot of total temperature (through the middle of the combustion chamber).
I'm still having some troubles with a fuel injected model/run/simulation, so in this particular case, it assumes that it is a homogenous mixture (fuel: mass fraction of 0.87 2,2,4-trimethylpentane, 0.13 n-heptane; mixture fraction = 0.1) (in normal people English that would be 87 "octane" (AKI) pump gas, but a simplified reaction model, air-fuel ratio of 10:1.)
I think that it's got like a total of 193,000 elements, and the run took a total of 41.4 hours.
The one that I've got running (actually, I've got two running) - they're both the same fuel injected model, but one's running with single precision (to 533 degrees crank angle - right before where it failed the last time it ran) and the other is going to try to run the full 720 degrees crank angle but using double precision. The first run is expected to take 44 hours (on 2 CPUs) while the second, double precision run is expected to take 72 hours on 8 CPUs).
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