Tailoring Lubricant Formulations to Cylinder Cond

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Tailoring of Lubricant Formulations to Localized Power Cylinder Wall Conditions

https://dspace.mit.edu/bitstream/handle/1721.1/98583/921140910-MIT.pdf;sequence=1

Pro...it's "fresh", and not relying on "old papers as gospel".
Con...it's a thesis, which apparently can't be trusted.
Con...there's modelling, which apparently can't be trusted either.

IMO...
Has some great data and correlations, viscosity, wear, and the optimisation of wear and usable life as a design parameter.
Recommends J300 be rewritten (a different take on it to mine).
Has an interesting twist on volatility in the top ring area, volatility increasing the localised viscosity in the top ring area...have posted papers before showing that additive concentrations in the top ring area are increased due to volatility, so more adds plus more viscosity is probably beneficial in that zone.
Contains surface roughness and ring wear predictions/measurements for calibration.
Has a newbie error in the HTHS description, same error spent a decade in 101.
Suggests compartmentalising lubricants for future engines (whodathunkit??)

It's certainly worth a read.
 
Now we are definitely into the La-La land of trade secrets. IE; why some oil seems to perform better than others. Not talking Redline, etc. But basic fleet oils like Delo and Delvac. Oils with a proven track record of engines lasting 1,000,000 miles (historically) w/o an overhaul.

It is their tribology and their lab work to make these blends. Chevron has patents for "synthetic" lubricants going back to the 1940's but does not really push them. They have made a very good dino oil forever. What makes them good?

I suspect this paper has illuminated some of the reasons, including volatility as tool to increase viscosity in the upper ring area as a counter to load/heat...

This thesis was overseen by some well respected researchers. So I'm surprised that the "goofs" got through. But hey, stuff happens...

However, the basic background info is still useful and relevant
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So I wonder how the GTL crowd is doing in this regard? Making unique AW compounds as oil ages in an engine seems to me to be one key. But if you start with less rich chemical mix, does it take longer to make such compounds?

And is there good volatility vs bad volatility? Will some oils only thicken, and others actually coke a ring land? Inherently we know this can happen. But I'd like to know which oils exhibit best usable volatility
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Not something I've ever seen published ...
 
You make great points on the HDEO - and also how these majors work. Since you mentioned patents and GTL - folks have posted how Mobil has fallen behind on GTL. They like others to go kick the tires. At the point they decided to move GTL funding to increase production - they held 3500 GTL patents and have been into major LNG for decades. They make decisions based on ROCE and keeping certain partners happy. They have recently invested in upgrading to produce the lower groups of base oil. I run several 7000 HP engines off that horrible oil ...
 
There is little to no point in GTL with crude prices as low as they are. GTL was only to utilize previously vented natural gas but it turned out to be an expensive venture even with free feedstock.

You still have to hydrocrack the output, so why go through the additional synthesis steps?

Originally Posted By: 4WD
You make great points on the HDEO - and also how these majors work. Since you mentioned patents and GTL - folks have posted how Mobil has fallen behind on GTL. They like others to go kick the tires. At the point they decided to move GTL funding to increase production - they held 3500 GTL patents and have been into major LNG for decades. They make decisions based on ROCE and keeping certain partners happy. They have recently invested in upgrading to produce the lower groups of base oil. I run several 7000 HP engines off that horrible oil ...
 
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