Remember the OPOC engine? That is the opposed cylinder 2 stroke we mentioned last December. It looks like it’s getting interest from investors, notably, Bill Gates, who just contributed $23.5 million to help them complete engineering and testing. Gates has been investing in all sorts of alternative energy companies and projects, his funding here certainly raises the chances the engine will survive long enough for development to move ahead.
Link: Wall Street Journal
Willie says
Looks like somewhat of an improvement over this design:
http://en.wikipedia.org/wiki/Junkers_Jumo_205
todd says
I wonder what BG’s ROI expectations are? Hopefully they’re not as big as the US Energy Department, they’re releasing $25B for just this sort of thing. Hopefully the company I’ve done work for will get some of it as we have applications in right now. Or, maybe we should be talking to Mr. Gates.
http://query.nytimes.com/gst/fullpage.html?res=980CE7DA1E38F931A35751C1A96E9C8B63
-todd
pete says
lol–how to tell you have too much money
Michael W LexPk MD says
Even if it turns out to be the greatest 2-stroke bike engine of all time, it is illegal to sell 2-stoke bikes here, so what difference would it make.
Good luck and ride safe.
Phoenix827 says
I like this engine a lot. I feel it would be especially suited to a diesel application. I am, however diesel biased. I run a homebuilt diesel bike and get about 110mpg. This engine would weight half the engine in my bike and put out more. Fuel consumtion would be my concern.
J says
I don’t know where you are, Michael, but it is not illegal to sell 2-stroke bikes in the US.
The issue has historically been related to emissions. The designers claim this engine is much cleaner than previous 2-stroke designs.
WestOfBen says
For sheer simplicity I like the OPRE engine:
http://www.pattakon.com/pattakonOPRE.htm
Merlin says
I’m with phoenix on this. 2-stroke gas engines have the advantage of being small and powerful, but sacrifice efficiency. 2-stroke diesel engines are powerful and efficient, but sacrifice compactness. The biggest advantage of this layout seems to be its compactness, which would be most beneficial to the latter. As a diesel, this engine could be powerful, efficient, and compact, the great triumvirate of engine design.
Also, one of the other big drawbacks of 2-stroke diesels is a low and narrow powerband. This certainly might help, though at the cost of efficiency.
Paulinator says
There are MANY undeveloped and under-developed engine concepts that have emerged over the last 125 years. Is this engine better than the rest? The pistons are round and running in cylindrical bores, there is no attempt to eliminate mythical “reciprocating losses” and the sliding parts aren’t used to ground the torque that is generated. Looks better than most, IMHO.
Is Bill Gates’ backing enough to push this thing to production? I don’t know, but I think he should get behind something that would replace the venerable GY6 scooter power plant and other similar drives…then he would make another global impact.
todd says
Here’s what they’re up against:
A typical 2-stroke engine used in a motorcycle emits hydrocarbons at 17.3 grams/mile (111g/mi for a snowmobile). A 2002 Ford Expedition 4X4 (can it get any worse?) emits 0.15 grams/mile. A Yamaha R6 is closer at 4.19. Though motorcycles won’t be expected to meet passenger vehicle standards they are still trying to update motorcycle emissions standards from 1977… I believe 2010 is when EPA Harmonized emissions across all 50 states, i.e. no more 49 state models.
This is what the manufacturers of 2-strokes are up against, and they’ll need all the money they can get. The new standard for motorcycles will be 1.3g/mi but I haven’t looked up the standards for non-vehicle engines where this is more likely to be used.
Meanwhile, go find yourself a RD350LC and relish the fact that EPA standards are not retroactive.
-todd
dan says
This engine is set to make all electric vehicles obsolete. The designer hails from VW’s diesel department and may be the man responsible for the top engine today in my opinion the TDI clean diesel. It is though that a major auto manufacture will buy the rights to this engine. GM hello!
searcher3 says
When you watch most videos on the opoc engine,you can see that the engineer has separeted the burned gase from the fresh ones,therefore correcting the biggest problem( emission) of the 2 stroke design.A 2 stroke design can develop more than twice the power than a 4 stroke,without the complexity of multiple poppet valves,cam chains,etc.You have to ask the buyers of the newer 450cc 4 stroke dirt bikes,about the rapid wear and tear of the engines,and the very high cost of repair /replacement of the 4 stroke dirt bike engine.
Manousos Pattakos says
Quote from an interview of CEO Don Runkle (OPOC engine):
“The OPOC, according to Runkle, is cheaper, better, simpler, stronger, lighter and cleaner than any other power generating technology now or in the foreseeable future. . .The engine’s width is exaggerated a bit . . .â€
The OPOC
The two external pistons of the OPOC are the good ones. Their arrangement and lubrication is similar to those of the cross-head engines. A drawback is the necessarily long and heavy piston pin that extends well outside the cylinder. Another drawback is the two long and heavy connecting rods per external piston (about 2.5 times longer than the single connecting rod of the internal piston) and the increased number of crankpins and bearings.
As compared to a piston performing a pure sinusoidal motion of the same stroke, the external piston of the OPOC moves more slowly around the Combustion Dead Center (CDC). This would improve the combustion efficiency, yet they come the internal pistons to spoil this advantage. The internal pistons of the OPOC move, around the CDC, more quickly than a piston performing a pure sinusoidal motion of the same stroke. Finally the volume between the two pistons and the cylinder increases, around the CDC, more quickly than in case of pistons performing pure sinusoidal motion.
There is also a difficult lubrication issue with the internal pistons of the OPOC, especially the one thrusting over the exhaust ports. The hot cylinder with the exhaust port slots is where the piston skirt has to touch (to slide, to abut) in order to pass to the cylinder the thrust loads generated by the inclination of the connecting rod. The problem is that increasing the quantity of the oil at the exhaust port area of the cylinder, the oil consumption (it escapes at the exhaust) is also increased and the quality of the oil degrades sooner.
In order to counterbalance the first order inertia forces and moments, the OPOC engine has to use internal and external pistons of the same reciprocating mass (it is the mass of the piston, of the piston pin and of the upper part of the connecting rod mass). Yet each internal piston has a small piston pin and a single short connecting rod, while each external piston has two long and heavy connecting rods and a big and heavy piston pin. The solution (?) is to add mass to the internal pistons. This increases the inertia loads and the friction loss. Besides, it is the offset between the two cylinders of the OPOC that generates a 2nd order unbalanced inertia moment. There is also a strong unbalanced inertia torque of 2nd order (just like in any four in-line conventional engine).
The OPOC engine is so long (wide) because it is based on an opposed cylinder to counterbalance the inertia loads. Despite all this complication (four pistons, two short connecting rods, four long connecting rods, two cylinders) the “vibration-free†or “balance quality†of OPOC is not exceptional.
Another issue is the different timing, during the scavenging, of the one cylinder as compared to the other: The cylinder that uses the internal piston to controls the exhaust ports aspirates differently than the cylinder that uses the external piston to control the exhaust ports. This asymmetry may be compensated at some revs and loads, yet it cannot at a wide rev and load range.
Finally, the scavenging process (i.e. the most critical and power consuming process in a two-stroke engine) of the OPOC is realized externally by a turbo-charger (not the ideal solution for engines that operate in a wide rev and load range).
The OPRE
Take now the OPOC engine, throw away the two internal pistons, throw away the four long connecting rods, throw away the two long and heavy piston pins and replace the unique multi-crank-pin crankshaft by a pair of single-crank-pin crankshafts located outside the pistons. What is left is the OPRE engine.
The OPRE needs not long connecting rods neither an opposed cylinder to be “vibration-freeâ€. And its width is more than 30% smaller than an OPOC of the same piston stroke.
The combustion takes place at the slow dead center that provides a 30 to 40% additional time (as compared to the conventional engine) and a 20% additional time (as compared to the OPOC) to the fuel to get prepared and burned more efficiently. This extended piston dwell at the CDC allows a way higher rev range (it allows Direct Injection Diesels operating efficiently at 6000 rpm).
If the one combustion per crank rotation is not adequate, additional OPRE modules can be added in series to make a multicylinder OPRE engine.
By using the external side of the pistons (i.e. the wrist pin or cool side of the piston) as a “zero†cost, zero friction volumetric piston-type scavenging pump, the OPRE takes its final form. If the forced induction (turbo-charge) is desirable, it is OK for OPRE, because it can operate efficiently with and without turbo charging.
The integrated volumetric scavenging pumps of OPRE allow the operation either with symmetrical timing or with asymmetrical timing between the intake and the exhaust.
Especially in case of divided load (for instance as a power generation set, or range-extender, with one electric generator on each crankshaft) the NVH properties of the OPRE range-extender are the best among the internal combustion engines, the Wankel rotary engine included. The OPRE range-extender is not only perfectly free of inertia vibrations, which is also true for the Wankel range-extenders, but it is also free from power pulses vibration on its mounts (supports) which is not the case for the Wankel range-extenders: each combustion into the Wankel rotary engine causes a reaction torque (power vibration) on its supports.
An unconventional application: with a couple of counter-rotating propellers the reliable, lightweight, efficient and true vibration-free OPRE makes a portable Flyer (presented at http://www.pattakon.com/pattakonFly.htm ). We think the OPRE Portable Flyer can change the world. Yet we have to fly first, to prove it.
Despite what CEO Don Runkle (OPOC engine) claims, as compared to the OPOC engine
the pattakon Opposed-piston-Pulling-Rod-Engine (OPRE engine) is:
more compact,
lighter,
simpler,
cheaper,
is based on “built-in†scavenging pump of the piston type,
has a wider rev range,
is more vibration-free,
provides additional time to the fuel to get prepared and burned more
efficiently,
has better lubrication, etc.
For more (videos of the OPRE prototypes running on Diesel fuel,
dimensions, weight etc): http://www.pattakon.com/pattakonOPRE.htm
Thanks
Manousos Pattakos
Manousos Pattakos says
Here
http://www.pattakon.com/pattakonPatOP.htm
you can see the PatOP engine.
The PatOP engine is the single crankshaft version of the OPRE engine.
Thanks
Manousos Pattakos
Paul Ellis says
Oh Dear, all this extra complication added to a basic two-stroke design.
I loathe the extended transfer passage lengths, fancy gearing, extra crankshafts, etc.
How on earth is all this supposed to result in better volumetric efficiency and improved thermodynamics for a revised two-stroke design.
My own design has few parts, an extremely high flow coefficient for both transfer and exhaust, a cool side for heat rejection and a hot side for heat addition, both at constant volume (3millisecond piston dwell at dead centre positions at 34,200 rpm.) together with 1/6th the heat flux area of a conventional engine.
Effective piston cooling allows BMEP’s up to 460 psia without distortion. Expansion ratio is 3 times the compression ratio.
The 500cc prototype is due for completion end of this month (November 2010) and development is due to be undertaken with government funding, beginning 2011.