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Ford going to opposed piston engine in Ford F150

Ford going to opposed piston engine in Ford F150

Ford going to opposed piston engine in Ford F150

(OP)
there was a story that came out yesterday that ford intends to install opposed piston engines in it's F150 trucks. http://achatespower.com/our-formula/opposed-piston...

B.E.

You are judged not by what you know, but by what you can do.

RE: Ford going to opposed piston engine in Ford F150

(OP)
My Bad,
The story was a re issue of a story that came out in January.
B.E.

You are judged not by what you know, but by what you can do.

RE: Ford going to opposed piston engine in Ford F150

Probably not all it is cracked up to be, either. Having that piston arrangement doesn't magically solve anything and it certainly introduces a lot of its own headaches.

RE: Ford going to opposed piston engine in Ford F150

Double knocker engines. Great to see 1950s technology being revisited. Quick thought experiment, how much of the combustion chamber's heat energy is lost in the cylinder head? or via the piston?

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: Ford going to opposed piston engine in Ford F150

The Commer Knocker (and Fairbanks Morse) opposing piston engines were built decades ago. They did not take over the market then. What, fundamentally, is different now? Physics hasn't changed ...

RE: Ford going to opposed piston engine in Ford F150

(OP)
Greg ,
Double knocker 1950s how about 1930s The Junkers Jumo 204 looks a lot like the ford engine.
B.E.

You are judged not by what you know, but by what you can do.

RE: Ford going to opposed piston engine in Ford F150

Brian; One thing that has changed is stringent exhaust emission regulations - it is hard enough to meet current regulations cost effectively with 4-stroke engines, and harder still with side injection piston-ported 2-stroke combustion systems. I am not saying that it can't be done, but to reach these levels, the industry as a whole had to concentrate on one approach and make it work. 4-valve central injector 4-stroke combustion systems looked like an easier mountain to climb at the time.

PJGD

RE: Ford going to opposed piston engine in Ford F150

Physics may not have changed, but technology enablers (notably material science and electronic control) have. A good but impossible idea may now be a good and possible idea. Nothing's new, but some things are becoming practical.

Steve

RE: Ford going to opposed piston engine in Ford F150

Some of the experts here should let the Army know it's wasting the $47.4 million they awarded to Cummins and Achates.

"Cummins Inc. has landed a $47.4 million contract from the National Advanced Mobility Consortium to develop a revolutionary new type of diesel engine for the U.S. Army that promises to be lighter and more efficient than those currently in use. The Advanced Combat Engine (ACE) project is a joint venture between Cummins and California-based Achates Power, who has designed an opposed-piston engine that works on a two-stroke combustion cycle and eliminates the need for a valvetrain."
https://www.foxnews.com/auto/cummins-developing-re...

Physics haven't changed, but material science, design refinement technology (.e. CFD), and adaptive control sure have.

RE: Ford going to opposed piston engine in Ford F150

The US Army also blew millions (back when millions was real money) on the adiabatic ceramic engine. Selling transformative pie in the sky to defence forces is like robbing a baby. It's other people's money, all the officers want is to be associated with a successful, preferably fun, project.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: Ford going to opposed piston engine in Ford F150

I think that the fundimental problem of opposed piston two strokes is that the combustion chamber is of necessity the same diameter as the cylinder . this produces a problem of shape and admission of fuel from the side injectors . the exhaust piston is subject to much heat from combustion and exhaust flow . the engine is also not a natural overexpander like the Atkins cycle and relies entirely on a supercharger to run .

Link this one is an overexpander but I am not sure how much strain or load that crank mechanism can stand
Opposed piston fourstroke ?

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare
www.sixstroke.com

RE: Ford going to opposed piston engine in Ford F150

Greg, if they fooled anyone, it was Cummins (who put Achates under subcontract), and Cummins knows a bit about engines.

RE: Ford going to opposed piston engine in Ford F150

malbeare,

Achates published an SAE paper you might find interesting titled "Thermodynamic Benefits of Opposed-Piston Two Stroke Engines" available at http://achatespower.com/wp-content/uploads/2015/04....

Quoting from the paper abstract, "The simulation results showed that combining the opposed-piston architecture with the two stroke cycle increased the indicated thermal efficiency through a combination of three effects: reduced heat transfer because the opposed-piston architecture creates a more favorable combustion chamber area/volume ratio, increased ratio of specific heats because of leaner operating conditions made possible by the two-stroke cycle, and decreased combustion duration achievable at the fixed maximum pressure rise rate because of the lower energy release density of the two-stroke engine. When averaged over a representative engine cycle, the opposed-piston two-stroke engine had 10.4% lower indicated-specific fuel consumption than the four-stroke engine."

On the other hand, EcoMotors was working a similar design but appears to have closed in January of this year. It's not clear why they closed down. It may have been because they encountered problems or because their investors pulled out due to Achates' overwhelming lead. See https://en.wikipedia.org/wiki/EcoMotors

Rod


RE: Ford going to opposed piston engine in Ford F150

This is stolen technology from Fairbanks Morse, they have been making this style engine for decades even into the now time. Also they have the most efficient diesel engine there is for the size. It looks to me like they (FM) have redesigned the dual crankshaft drive system from what it was, as well as a few other changes.
Unless this engine in the ford is made from CGI rather than what looks like Al, it will be a failure.

RE: Ford going to opposed piston engine in Ford F150

Quote (enginesrus)

This is stolen technology from Fairbanks Morse, they have been making this style engine for decades even into the now time.

Fairbanks Morse didn't invent the opposed-piston engine. Nor the opposed-piston two stroke engine, or the opposed-piston diesel.

RE: Ford going to opposed piston engine in Ford F150

"...let the Army know it's wasting the $47.4 million they awarded to Cummins and Achates."

'Appeal to Somebody-is-Spending-Money' arguments aren't very convincing. They're several logical steps below 'Appeal to Authority' arguments, which are already extremely unconvincing.

RE: Ford going to opposed piston engine in Ford F150

VE1BLL,

I was reacting to the out-of-hand dismissal of Achates' work by armchair quarterbacks. Healthy skepticism is always appropriate, but where in rank relative to "Appeal to Authority" do you place off-the-cuff dismissal? Cummins is a well known engine manufacturer, and they presumably reviewed the design and prototype data before selecting it. Does that mean they're right> Of course not. They're opinion is, however, likely to be rooted in better information and understanding than the armchair quarterbacks.

Ford isn't the first to evaluate Achates. DARPA, DOE, and the Army has reviewed and funded their work, and Fairbanks Morse (who know the engine well) are adopting Achates designs for their own use according to www.wardsauto.com/engines/achates-opposed-piston-e....

There are challenges in opposed piston engines, but there are also benefits to the architecture. Time will tell if Achates has overcome those challenges and can deliver on the benefits.

Rod

RE: Ford going to opposed piston engine in Ford F150

I was merely pointing out that the US Army's track record with new engine designs shows little proof that it is a viable design. I said nothing about Achates current work, and asked a technical question which was directly relevant, which was ignored in favor of grandstanding.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: Ford going to opposed piston engine in Ford F150

I never said FM invented it or the diesel. The design is something that they have had for I'm guessing close to 80 years. I just don't think its right for Achates to be advertising themselves as the great founders of the design.
And out of all the other outfits to ever use that design FM has been the longest, and has established a great record of durability with it, when everyone else gave up with it. So funny that this design could be the one that saves the recip piston engine and moves it farther into the future, especially when everyone is and was giving up on the 2 cycle design.

RE: Ford going to opposed piston engine in Ford F150

There is a big difference between accepting funding money and endorsing what you've been funded to study.

Steve

RE: Ford going to opposed piston engine in Ford F150

There is a risk to accepting funding and failing to succeed. It can make future contracts more difficult. This is not pure research; it's to improve or apply an existing concept and if the company is unable to make a decent estimate of that it calls into question what else it might have problems with.

No one cares if the task was impossible, they care that someone said they would deliver and failed.

RE: Ford going to opposed piston engine in Ford F150

"Ford isn't the first to evaluate Achates..."

Is Ford involved here?

The linked article states "Testing in a Ford", which is not really the same as Ford (the company) being involved.

Perhaps I've missed something.


RE: Ford going to opposed piston engine in Ford F150

GregLocock,

I apologize for "grandstanding." It was the product of my frustration with off-the-cuff dismissal. I believe the technical question you put forward "how much of the combustion chamber's heat energy is lost in the cylinder head? or via the piston?" is answered by the article I linked in response to malbeare. The article at www.proctorcars.com/redesign-internal-combustion-e... also sums up the potential benefits that are behind the effort to resurrect the opposed piston architecture:
  • Thermal efficiency: Low ratio of combustion-chamber surface area to cylinder swept volume and elimination of cylinder head mean there's much less heat rejected to the cooling system so more of the heat of combustion goes to propelling the vehicle.
  • Lower friction: With no cylinder head bolts to distort the bore, there's less ring friction, and the lower peak operating speed of any compression-ignition engine lowers friction.
  • Lower pumping work: Intake and exhaust enter and leave via ports arranged around the cylinder at the top and bottom of the pistons' strokes, so the pistons do no pumping work. With some of these ports open at all times on an engine with three or more cylinders, the supercharger and turbo also operate more efficiently.
  • Lighter weight: Lower cylinder pressures mean that even the diesel doesn't need to be "hardened" to the same extent as a conventional four-stroke diesel.
  • Cooler operation: Lower peak cylinder pressures and temperatures reduce the amount of NOx and other pollutants produced in the cylinder.
  • Horizontal direct injection: Two fuel injectors spray across the cylinder instead of onto the hot pistons, which can cause the quenching that leads to particulate formation. Also, the stroke is long enough to fully burn the hydrocarbons.
There are a number of challenges to the design that the article doesn't mention.
  • Lack of piston load reversal: Like any two-stroke the rings and bearings suffer unidirectional loads that create problems in lubrication.
  • Lubricant in the ports: Like any two-stroke, oil around the rings can pass into the intake and exhaust ports.
  • Fuel/Air mixing: Side sprays simply aren't as effective in mixing, particularly given the reduced time available.
Rod

RE: Ford going to opposed piston engine in Ford F150

The only explanation that makes any sense to me with regards to the lower heat loss to the combustion chamber of an opposed piston engine is possibly the fact that the two pistons moving away from each other have twice the expansion rate of a single piston moving away from a fixed head *deep breath*.It's kind of like running a crankshaft and rod geometry that promotes a short piston dwell time but without the disadvantages of rapid piston acceleration and high rod angularity.

RE: Ford going to opposed piston engine in Ford F150

Just to reply to the challenges, I don't think any of those are truely valid.

Load reverals are tremendously more difficult to deal with. If you look at the architecture of our favorite 2-stroke engines including EMD and Detroit Diesel, the lack of load reversal so simplifies the bearing arrangements that they only have to use half of a bearing. See the blade rod bearing and piston carrier bearing in an EMD and the wrist pin bearing in a cross-head type Detroit Diesel 71 series engine.

Lubricant in the ports doesn't directly equate to particulate in the exhaust. Valved engines have valve guides that do allow oil directly into the exhaust where it can combust poorly. Fully ported engines may actually see an advantage here.

Side injection isn't necessarily a bad thing. Fuel can travel the full diameter of the bore vs only half with a centrally injector prior to being quenched. However, I think an advantage of an opposed piston design is that it allows for a much larger combustion chamber vs. bore diameter due to having essentially twice the stroke without the issues of the connecting rod crashing into the bottom of the cylinder.

RE: Ford going to opposed piston engine in Ford F150

The only explanation that makes any sense to me with regards to the lower heat loss to the combustion chamber of an opposed piston engine is possibly the fact that the two pistons moving away from each other have twice the expansion rate of a single piston moving away from a fixed head *deep breath*.It's kind of like running a crankshaft and rod geometry that promotes a short piston dwell time but without the disadvantages of rapid piston acceleration and high rod angularity.

Yes. As far as heat loss and the thermodynamic cycle in general, the OP has all the advantages of a long stroke design while having the mechanical advantages of a short stroke.

je suis charlie

RE: Ford going to opposed piston engine in Ford F150

I doubt they'd be able to efficiently do it within regulations anyhow

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