Shell presentation on oil, economy, and future.

[Shannow]

Ian Taylor Shell paper.

Not wanting to add too much commentary until some of the better regular posters have a look, and comment, given that many of the points made in the preso I have made before and been slammed as lying, technical obfuscation, or purveying misinformation.

 

[oilmutt]

This is way over my head,I love the charts even they were Greek to me!

 

[wemay]

Just a few take aways.

Conclusions

Overview given of:
Key drivers: Energy efficiency, CO2 reduction
Moving to energy efficient lubricants is cost effective compared to
hardware modifications
Direct engine measurements demonstrate that moving to lower viscosity
engine lubricants results in lower engine friction
Synthetic based gearbox and axle lubricants also shown to result in
higher transmission efficiencies than mineral based oils
These changes result in significant fuel consumption benefits with such
oils
However, oil film thicknesses will be smaller – care is needed to ensure
lubricants also give adequate durability
Lubricant properties can give insight into friction/fuel consumption
provided the correct properties are used

But this was intriguing...

High VI oils
At low temperatures, the high VI oil (Oil A) will give better fuel economy
than Oil B. However above 140°C Oil A will give a higher oil film
thickness than Oil B – therefore Oil A can give good fuel economy under
most normal driving conditions, whilst giving higher oil film thickness
under “extreme” conditions

 

[Koz1]

I don't know why this is controversial at all, reduce friction increases efficiency. It makes sense and to be honest what I expected.
They even use MoDTC to reduce friction, cool.
Could you expand on the points some members here have issues with.

 

[Shannow]

Pretty well the conclusions page
* Driver is CAFE/carbon;
* low viscosity lubricants are the cheapest means of achieving that outcome;
* offering lower levels of protection (MOFT, and as demonstrated TDC ring friction);
* inserting charts and formulae is "technical obfuscation", rather than demonstration.
* manufacturers are managing reduced protection, while some posit that lower viscosity is "improved" protection.
* reduction in friction is not the same as reduction in wear
* PAO have some clear benefits
* importance of viscosity and additives in the different regimes on the Stribeck Curve.

(one not touched is the transition from cold to hot, as the lubricant moved from cold and viscous to hot, thin, and additives activated).

 

[wemay]

You lost me at... 'reduction of friction is not the same as reduction in wear.'

 

[Shannow]

wemay, go to the Stribeck curve on slide 3.

The area of mixed lubrication is the lowest point on a traditional stribeck diagramme.

Areas to the right are full oil film, the parts are kept separated by the motion of the bearings, and the viscosity of the lubricant...they don't touch, and are considered "zero" wear...the lubricant drags on the shaft, and causes friction, which is a power loss, but the parts don't touch/wear.

The mixed lubrication point is the least friction point, but also has regular contact between the parts being lubricated...they wear. Efficiency traded off against wear.

Of course, as per my warm-up thread, things are friction modified for the lighter oils these days (less to no FM in many of the thicker 40s)...these oils produce less wear in the partial contact regime.

 

[wemay]

Originally Posted By: Shannow
wemay, go to the Stribeck curve on slide 3.

The area of mixed lubrication is the lowest point on a traditional stribeck diagramme.

Areas to the right are full oil film, the parts are kept separated by the motion of the bearings, and the viscosity of the lubricant...they don't touch, and are considered "zero" wear...the lubricant drags on the shaft, and causes friction, which is a power loss, but the parts don't touch/wear.

The mixed lubrication point is the least friction point, but also has regular contact between the parts being lubricated...they wear. Efficiency traded off against wear.

Of course, as per my warm-up thread, things are friction modified for the lighter oils these days (less to no FM in many of the thicker 40s)...these oils produce less wear in the partial contact regime.


Got it, will do.

 

[Solarent]

Here is my take on your list:
Originally Posted By: Shannow
* Driver is CAFE/carbon;
Yes and no. While CAFE rules and carbon reduction is on the list, the expectations of consumers are also there as well. Everyone wants fuel efficient vehicles (that can run for 1000 miles between fill ups) and still get the same levels or higher of performance. If you look at the SUV category for example, comparing a 2004 MY to 2014 MY - the engines have gotten smaller, vehicles lighter, but they have more power, they are bigger in size, and they are more fuel efficient. This is what is being demanded and the industry (with some help from regulations) is responding.

Originally Posted By: Shannow
* low viscosity lubricants are the cheapest means of achieving that outcome;
its one of many ways - looking at the heavy duty segments, things like aerodynamics and rolling resistance were the "low hanging fruit" in the fuel economy game. Now that those have mostly been beaten to death, there are some real opportunities moving some of those engines to lighter grades than the 15W40. It happened in PCMO and now HD is following suit.

Originally Posted By: Shannow
* offering lower levels of protection (MOFT, and as demonstrated TDC ring friction);
I disagree with this statement because it assumes that MOFT is the only protection provided by the oil. Because of advancements in friction modifiers and antiwear chemistry, the industry is saying that it IS POSSIBLE to create lower viscosity fluids which are inherently more efficient in Hydrodynamic conditions and still provide equal or better protection in boundary and mixed lubrication conditions.

Originally Posted By: Shannow
* inserting charts and formulae is "technical obfuscation", rather than demonstration.
sure. but unfortunately the general consumer doesn't know enough or care enough - even though there are real benefits to taking advantage of some of these better lubricants.

Originally Posted By: Shannow
* manufacturers are managing reduced protection, while some posit that lower viscosity is "improved" protection.

Yes maybe - but this is because in some cases it is possible to protect better and be more efficient with lower viscosity fluids.

Originally Posted By: Shannow
* reduction in friction is not the same as reduction in wear
* PAO have some clear benefits
* importance of viscosity and additives in the different regimes on the Stribeck Curve.

No arguments here on any of these.
It is without question that the industry is moving towards an era of efficiency and looking at every possible option for creating vehicles with better fuel economy and lower impact. Some of the things that are being developed for the new thinner lubes (probably not available until GF-6 and PC-11 are finalized) are pretty cool. When people get hung up on the idea that these oils are going to be too thin to properly protect engines they aren't looking at the whole picture. You will see more and more synthetics, higher VI, denser additive chemistry and more complex fluids.That's just the way it goes - and I for one find it an exciting time to be a part of the industry.

 

[Shannow]

Solarent,
thanks for your input (as usual, good background information).

I agree it's exciting times.

Can I take from your conversation that more mixed lubrication is the way of the future ?

(It's usually another bone of contention when I mention that, particularly using the GF6 test cycles which test more in mixed than previously).

 

[Solarent]

Yes Definitely.

The balance for mixed lubrication is likely to continue (which is really where the elastohydrodynamic regime is). In a properly formulated low viscosity oil you have this beautiful marriage between the bearing materials and design, the viscosity (from the base and VM's) and the additive package. This requires more robust surface activated chemistry and is driving new developments for protection in what was the high friction boundary conditions. What that means is if we were creating low viscosity lubricants with the same additives we used for GF-5 there could be issues but the new designs for 0W16 oils are purpose built to run in the elastohydrodynamic regime. I expect theyt will be quite different than what we have seen in the past. (more of a focus on boundary film formation and oxidation resistance)

The more that the lubricant becomes a design choice by the OEM's, I think we will also see them wanting to control more the kind of engine oil that goes in. In order to do that in North America, it will require free or included oil changes from the dealership - which is something some dealers are already pushing for. I just picked up a new Explorer Sport and they offered to give me a deal on a 5 year service plan which included all my basic maintenance. (Oil changes,filters etc)

 

[MolaKule]

Originally Posted By: Solarent
...You will see more and more synthetics, higher VI, denser additive chemistry and more complex fluids....


And it gets more exciting every day, with chemistry such as ILs, OSPs, new anti-oxidants, new AWs, new VIIs, new friction modifiers, and new esters such as polymer esters.

 

[userfriendly]

In the last 12 months or so I've read just
about everything Shannow has put in front
of us, the last being that thesis from
Nottingham.
What, 250 pages?
I think I know what makes Shannow un-easy
about all this talk of boundary and
elastohydrodynamics in plain bearings.

It scares me too, and it may be a symptom
of information overload.
Too many what if's.
(What if we opened up the bearing clearance instead?)

I agree with Solerant, (no doubt a Flames fan).
The vehicle manufactures likely offer extended
maintenance programs so they can control the
engine oil that goes into your new vehicle.

And perhaps make adjustments based on a controlled
study and real feed back.

So much for a multi vehicle, one size fits all 0W16.
I think the future is;
"This oil goes in that engine,
End of discussion".

Now there is the mother of all "what if's?".

 

[Shannow]

used_Oil,
yep...the "zero wear" approach to plain bearings is full blown hydrodynamic lubrication...that's where my comfort zone resides, having been responsible for $B of equipment that wasn't going to be inspected for anything less than 30,000 hours in service, and was supposed to last 300,000 hours.

A consumer appliance (which a car is), involves rational compromises in extended life durability...another couple hundred gallons of fuel over the life of a car which is more likely to be rusted, wrecked, or tossed out costs the consumer $500-$1000, regardless of whether CAFE are in the mix or not.

It's rational design.

What gets me bent is the statements made that these oils are for improved durability, they work in this engine, so you should run your 3.8 on 2.6HTHS...and blanket statements that boundary isn't happening more in more modern engines.

So I keep looking at what information is out there, and cling to the gems that the likes of Solarent, Molakule, BobbyDavro, and Bruce 381 drop from time to time, and watch AZSynthetic's low vis extended OCI posts...sent one of my lower hose thermostats to Gary Allen, so he could control yet another parameter on his 0W10 jeep engine.

 

[OVERKILL]

Originally Posted By: Shannow


So I keep looking at what information is out there, and cling to the gems that the likes of Solarent, Molakule, BobbyDavro, and Bruce 381 drop from time to time, and watch AZSynthetic's low vis extended OCI posts...sent one of my lower hose thermostats to Gary Allen, so he could control yet another parameter on his 0W10 jeep engine.

 

[00Max00]

Originally Posted By: wemay
You lost me at... 'reduction of friction is not the same as reduction in wear.'


That's why there's no mentioning of wear anywhere.

 

[Ducked]

Originally Posted By: Solarent

The more that the lubricant becomes a design choice by the OEM's, I think we will also see them wanting to control more the kind of engine oil that goes in. In order to do that in North America, it will require free or included oil changes from the dealership - which is something some dealers are already pushing for. I just picked up a new Explorer Sport and they offered to give me a deal on a 5 year service plan which included all my basic maintenance. (Oil changes,filters etc)


Hooking the consumer in to the dealerships is a long-established strategy, because dealership servicing is a major profit source.

Previously I'm told its been achieved by things like proprietary diagnostic software/hardware, changed regularly to freeze out smaller independent workshops.

It makes perfect sense that some manufacturers would wish to extend this approach to lubrication, but its not necessarily an entirely positive development from the punters perspective.

 

[userfriendly]

Tables 11 and 12 page 109
and figure 51 of page 111 in the Nottingham
paper discussing eccentricity rates:

If that a product of bearing clearance,
the following should be true....

Increasing the bearing clearance
reduces the shear rate and resulting fluid
friction, and elevates the eccentricity rate
which increases the self-pumping oil
flow through the bearing and maintains
hydrodynamic lubrication with a thicker oil,
better than a thinner oil would with less
bearing clearance, which results in higher shear
rates, more friction, less eccentricity and
boundary lubrication.

Ha!

I knew I could edit 210 pages into one sentence.

The graphs on pages 119,120, 122, 131,133 and 143
have me going back to that paper.

 

[Ducked]

Originally Posted By: Shannow
wemay, go to the Stribeck curve on slide 3.

The area of mixed lubrication is the lowest point on a traditional stribeck diagramme.

Areas to the right are full oil film, the parts are kept separated by the motion of the bearings, and the viscosity of the lubricant...they don't touch, and are considered "zero" wear...the lubricant drags on the shaft, and causes friction, which is a power loss, but the parts don't touch/wear.

The mixed lubrication point is the least friction point, but also has regular contact between the parts being lubricated...they wear. Efficiency traded off against wear.

Of course, as per my warm-up thread, things are friction modified for the lighter oils these days (less to no FM in many of the thicker 40s)...these oils produce less wear in the partial contact regime.


Don't quite get your last point, since you seem to be implying a causal connection between more friction modifiers in the lighter oils, and lower wear.

This seems at odds with the "friction does not equal wear" message, unless (a) you didn't mean to imply such a connection, or (b) the friction-modifiers also act as (EP?) anti-wear agents.

I suppose if I knew what friction modifiers were involved, and how they worked, this might be clearer.

 

[Shannow]

In full hydrodynamic, it is oft described as "zero wear"...the components do not touch, and can't wear through contact.

In boundary/mixed, the original Stribeck model had greatly increased friction and wear, as there was contact, and surface welding etc.

In the Friction Modified Stribeck, (typically) there are surface films produced that have some of the base material as a part of it's structure...the friction is greatly reduced over boundary in a non FM world, reduced somewhat over full film hydrodynamic, but involves some contact and wear.