NewsW wrote:
BenK wrote:
What happened to lab testing? Do they have a true representation of
the real world in their labs (both simulation and hardware) ?
Couple points.
Simulations never do more than approximate the real world.
Yes, and have many discussions here and when still working
at the lab's...too many take simulation out of context to become the
end all.
Missing is that we humans have NOT discovered all of the laws of physics, yet
Simulation is just another tool, albeit a very good or bad dependent
on how management understands and directs it usage
If me at Bosch, I'd have looooooooong ago directed the engineers to
gather *ALL* of the cavitation DBs and load them into the super computer's DB
Then characterize all of the scenario's that can be thought up of and
that will be a continual process.
Then load all known DBs on DLC, (carboxylic acid-, ester- amide based and
organic amines, what else) material specifications and empirical data
Oh yeah, kinda sorta remember one of the original threads that got me
interested in this, was the mention of chromium as the base for the DLC,
which has the tendency to form micro cracks. Plus chromium must be
ground to attain the surface finish desired. Then the always issue of
hydrogen embrittlement when dealing with chromium on ferrous.
That stuff has been in practice for decades and should have a wealth of
information to also be loaded into the simulation DB
etc, etc, etc...and I'd be astounded if Bosch hasn't done so
That all then needs a real world proto-type(s) to confirm the
software simulations.
We are right at the end of summer mid fall, which is the official end (a few weeks ago) of biodiesel season where OP lives.
They only add biodiesel in the summer up there, because it cannot be used in the cold climates they experience up there.
In order to make up the amount added (by government dictat), they put in all of it in summer months, and none in the winter months because biodiesel cannot tolerate cold --- it gells.
To me, the prime suspect is more and more looking like biodiesel correlated.
Failure in this case is immediately after biodiesel season.
It is hydroscopic, and absorbs moisture that is not well separated out by the present water block membrane or fuel-water separator.
We now know CP4 doesn't like water.
But, why?...they have NOT found the root cause yet and looks like still
throwing band aids at it
With such a young engine and failure of like kind, a GREAT opportunity
for 'us' to gather information
Like how does the piston bottom look? Rick said his was hammered and
as I'd have thought with the way of the architecture (non-captive piston
bottom to cam follower and that the vacuum on the other end of the piston
would pull it off of the cam follower)
Exactly was the debris made up of?
Now that I've remembered chromium as the transitional coating between
the cam base material and DLC, looking for evidence of chromium in the
debris mix. Telling which gave way. Was there interaction with the various
acids and amines?
Since chromium is known to micro crack, were there crevices of unplated
DLC that would give cavitation a cool spot to lift from?
Back on H2O...how does H2O work with cavitation. Do know that it may
enhance the effects of cavitation (explosive steam micro bubble, etc)
In conjunction with the above mentioned acids and amines?
much more later after noodling it some more...
