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Brickley engine

Brickley engine

Brickley engine

(OP)
Those of you with engine friction experience have any  thoughts on the Brickley engine?

RE: Brickley engine

Interesting concept.  Looks like more mass in motion than a conventional IC engine, and an extra set of main bearings, if they would be called that.

RE: Brickley engine

It has a lot of oscillating bearings.  
I'm guessing they'd be in greatest need of hydrodynamic lubrication right where it's least likely available, near zero velocity.

 

Mike Halloran
Pembroke Pines, FL, USA

RE: Brickley engine

(OP)
Actually, the velocity issue and hydrodynamic lubrication (squeeze film) are addressed on the website's blog.  

RE: Brickley engine

I would suggest a zero-sum game; the large amount of mass in ever changing motion, (accel/decel) combined with a large amount of total bearings, would negate any implied improvement in friction.  But what the heck to I know...

RE: Brickley engine

boonebucker,

Just my opinion, but I fail to see how a larger number of sliding joints combined with a significantly greater amount of dynamic mass and reciprocating inertias, for a given displaced engine volume, will result in lower mechanical losses and/or improved brake thermal efficiency.

It's interesting that you inquired about "engine friction".  The largest friction loss fraction in a piston engine is due to pumping losses.  And this design does not seem to address those losses.

To paraphrase the old joke, it's just a "complex solution to a non-existent problem".

Hopefully, Mr. Brickley hasn't spent the family nest egg on this boondoggle.

Regards,
T

RE: Brickley engine

Better mousetraps and rube goldberg mechanisms do have some purpose, if only to serve as a transient to spark some other idea.  For the inventor or discoverer, the challenge is to acknowledge that your "baby" is mostly a novelty, and to discern well enough not to dump your life savings and someone else's into it.  We've all got patents and outstanding ideas, and I would parlay a guess that few of us are going to retire on easy street anytime soon.

RE: Brickley engine

(OP)
The example given on the blog uses a Willans line for a diesel. There are near zero pumping losses for the diesel at 1500 rpm. According to the graphs on the blog there is a huge difference between the friction at the at the wrist pin and the crank pin; approximately 1/15 the distance travelled per revolution and approximately the same load. Work lost equals FXd.

RE: Brickley engine

Its hard to conceive, but I think I counted 37 such wristpin type joints, including the large connecting rod little end.

Not all of the links have the same friction load while others have a disproportionately high load.  I can see packaging such a beast as a real problem, something a modern 4 or V-6 does reasonably well.

Wait a moment!  He lives in my town!  Why havent I heard of such a marvel?

Franz
 

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RE: Brickley engine

I'm guessing that if a physical prototype existed, you'd have heard of it and heard it.

- Steve

RE: Brickley engine

Arranging the drive to the valve gear could be a bit tricky.   

RE: Brickley engine

"The Brickley configuration reduces friction in several ways. First, it eliminates the piston skirts."

Ah, yes.  Because the nodding motion of the end of the H-shaped links (visible in the animation on the home page) forces the piston to move not in a straight line, but in a rotating or wobbling motion thru the cylinder.  So, you can't have a skirt.  Nor piston rings, or at least not conventional ones.  And the piston will then need to be a section of a sphere.  How does the piston seal?  

Eliminating piston rings will certainly help reduce friction.  But it will play heck with efficiency due to blow-by, at least until the pistons seize...

RE: Brickley engine

(OP)
The linkage at each piston is a Watt linkage. The center of the floating link is real real close to a straight line within the limits of the mechanism. This four bar linkage has been employed for it's linearity for over two centuries.

RE: Brickley engine

So it was well known and not selected for further development in ICs for over 10 years. I wonder why.

A Scotch Yolk has fully harmonic and zero side force on pistons and very few more parts but still was not used to any significant extent.

Regards
Pat
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RE: Brickley engine

I must be missing something. What is the purpose of all the little linkages where the pistons attach, at the end of each of the large pieces? There must be a pivot pin through the holes in the middle of the big pieces and then the piston/rod pieces attach to pins on the ends of the same pieces. those other parts at each piston seem to do nothing?

Still, I don't see this living up to the hype. I see nothing about the energy required to continually reverse the direction of all those pieces, just claims about removing some of the rotating bearing losses in the crank.

RE: Brickley engine

That is a component of the watts linkage previously mentioned.

RE: Brickley engine

The little linkages are indeed Watt links, which kinematically  drive the piston link in a straight line.
... if they are perfectly proportioned, and if the reaction hinges are stiff enough.

Given all that, the piston can use ordinary rings, doesn't need a huge skirt, and could probably have a round skirt, not an oval skirt.



 

Mike Halloran
Pembroke Pines, FL, USA

RE: Brickley engine

It's difficult to see the remainder of the linkage that is required to form a Watt's linkage.  I will give benefit of doubt to the OP, that there are additional links hidden under/inside the H-shaped linkages, and not readily apparent at first glance.  Having seen a lot of 3-D solid model animations, and knowing how simple it is to fake just about any motion you want using them, I am skeptical.  I will be less skeptical of this one now.

RE: Brickley engine

Ring to cylinder is one of the main points of friction loss.
This is another one of those internet designs that will go nowhere. Too much monkey motion. For simple recip you can't improve on whats already there.

RE: Brickley engine

If you want to eliminate skirt friction the easy way is to use a crosshead. This has the advantage compared with the Brickley of simplicity, and disadvantage that you couldn't patent it. I'd like to see one with a ballbearing rather than a slipper bearing as the guide.



 

Cheers

Greg Locock


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RE: Brickley engine

Using a different method of converting the linear motion to rotary motion will have little effect on the engine efficiency at the end of the day. The cost to tool up to mass produce a different engine with little net efficiency gain through the mechanics is a foolish gesture.

Until the crankshaft is eliminated the actual thermal efficiency over a drive cycle will only improve a small amount.

Ed Danzer
www.danzcoinc.com
www.dehyds.com

RE: Brickley engine

no friction at all, on a computer model......lol

RE: Brickley engine

If I had a dollar for everytime I've heard "well, it works on the computer!"

RE: Brickley engine

(OP)
I'm wondering if anyone is ever going to address the numbers, graphs, and the tribology that goes with the graphs on the blog. Maybe anything more than simple opinion is too much to expect.   

RE: Brickley engine

"The example given on the blog uses a Willans line for a diesel. There are near zero pumping losses for the diesel at 1500 rpm."

Uh, maybe at wide open throttle, but the example he uses is for a part throttle condition (1/6th throttle) - meaning losses at the throttle plate.

Extrapolating a Willans line as a linear fit...doesn't sound right to me.

There are better sources out there for estimating the mechanical friction losses of reciprocating engines.  The author should find these and cite them.  And not buried in a blog somewhere.

RE: Brickley engine

(OP)
I think 1/6th throttle means 1/6th load. No throttles for CI. Extrapolating a Willans as a linear fit is correct according to Gupta, Ganesan, etc. as long as the points chosen fit the linear part of the entire rpm map.  That appears to be the case here when all the points for 1500 rpm are included from the BSFC map. It's amazing how straight the fuel consumption line actually is.

RE: Brickley engine

Most of us here have seen, and perhaps participated in, at least one example of Computer Aided Self- Delusion.

If you want to convince this crowd that your engine has low friction losses, then you need to build one, and race it and make it survive in a motorcycle or a boat, with a vestigial or absent oil cooler.

 

Mike Halloran
Pembroke Pines, FL, USA

RE: Brickley engine

Ditto what Mike said.  Proof is in the pudding.  It doesn't sound like one has actually been built yet.  I personally believe that Chrysler was on to something in 1963/1964 when they put out 50 turbine cars as a test bed.

I agree that there is a far better way to convert a fuel  into performed work, but the IC reciprocating engine probably ain't it.  At the end of the day, you can't cheat physics.

RE: Brickley engine

(OP)
Maybe it's a delusion, maybe not. Sometimes" That's not going to work" is seeing. Sometimes"That's not going to work" is not seeing. The test is in a working prototype.

RE: Brickley engine

Feel free to use YOUR money to make one. I will not be contributing. I doubt anyone else who understands the laws of inertia and the nature of friction and the influence of the number of parts on costs and weight will either.

Regards
Pat
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RE: Brickley engine

(OP)
Being that you understand he "laws of inertia and the nature of friction" could you please address the following with great care: the efficiency with which the bottom end 5+ lbs of inertia is connected, started and stopped each revolution (twice per) in a 2 liter inline 4 cylinder and compare it to a Brickley configuration (connecting rod removed). Assume the Brickley has twice the mass( 8cyl mass equivalent) Address friction using the Stribeck curve "duty parameter" variables of load and distance traveled as the basis of comparison.

RE: Brickley engine

Bench racing is free.

How much have you budgeted for formal analysis?




 

Mike Halloran
Pembroke Pines, FL, USA

RE: Brickley engine

(OP)
Bench racing is fun too; at least for a little while. The formal analysis quote I received is no small pittance but methinks there might be another way. There's nothing like real numbers.

RE: Brickley engine

Not that long ago, one forum member and got into a heated debate with one other member.  The poster made a claim that he didnt care about the laws of physics, as "laws were meant to be broken".  He went to continue a diatribe about Columbus and the flat world, Copernicus, Newton, Einstein, and others who were proved themselves right, after the "experts of the time" claimed otherwise.

The proof is in peer review and replicating test results.  You have had your peer review from some of the industry top engineers.

Dont get me wrong, but we tend to be doubters until we see a working model.  Today's Solidworks and CAD works FEA development is VERY accurate and far less expensive than building a nuts and bolts model.

Franz

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RE: Brickley engine

(OP)
I couldn't agree with you more. Peer review and replication are the essence of science. I used Solidworks to build a prototype. It is a very powerful piece of software and can provide a great deal of very valuable information like FEA. I find myself always a novice with Solidworks. While I have found my own ways to model the friction associated with squeeze film lubrication (SAE papers etc.),  I have yet to find a Solidworks way to model the friction. Any suggestions?

RE: Brickley engine

I don't think Solidworks is the right tool for that.
Even if it could do it, I wouldn't trust the results without a physical correlation model, running and instrumented.

 

Mike Halloran
Pembroke Pines, FL, USA

RE: Brickley engine

[quote ornerynorsk}That is a component of the watts linkage previously mentioned.[/quote]

It's hard to see the watts link. Is the floating link the piece tying the large pieces to the H pieces? There just is no pivot shown in the middle of it making it very obscure to tell.
 

RE: Brickley engine

(OP)
You are correct. There is no pivot shown at the center of the floating link but that is where the fulcrum is located. Also I might add that while the kinematics of the animation are correct, the actual parts look quite different to address the issues of stress, inertia, balance, etc.

RE: Brickley engine

(OP)
    Might I suggest how the wheel "cheats physics." Does the wheel's gain not lie in the comparison of the distance traveled by the circumference of the wheel with the distance traveled at the circumference of the axle? The greater the ratio between the  distances traveled the lesser the friction. These distances traveled are the direct result of  diameters involved and the number of rotations, or partial rotations. This is how  twelve 20 mm wrist pins rotating through 70 degrees of rotation per revolution covers the same distance as only one 48 mm crankpin in one revolution. By sizing the pins to their respective loads great reductions in friction are possible; an amount greater than the contribution of the entire ring pack.
    Of primary importance here is the reduction of the distances that the areas of oil being sheared have to travel.

RE: Brickley engine

I would think the diameter of the journal bearings is defined by the load on them (the area required to sustain an oil film).as small as possible (ecomic and friction motives), as big as needed (oil film).The weight between the combustion proces and the crankshaft (piston,piston rod,...)adds to the load of the bearings (inertia)
just by putting one big piston with a crosshead,all the metal used for the pivotting levers could be used to build the rest of the vehicle.

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