Cummins opposed cylinder diesel engines for marine??

[ttmott]

Flat horizontally opposed common combustion diesel engines for military - compact 3 cylinder 6 piston 2 stroke 14L 1000HP.
Marine applications??
Not a new concept but now technically advanced with superior fuel economy.
It has got to sound interesting....

 

[DWABoat]

Well, interesting for sure. But…I thought the internal combustion engine was under the guillotine? Seems conflicting that domestic car manufacturers and fed gov will invest heavily in this new tech while simultaneously trying to dismantle the petroleum industry and ICE.

 

[Nater Potater]

Oh, yeah; opposed piston two-strokes are great for thermal efficiency and scavenging, plus, the vibration is virtually nil, with the pistons counteracting each other. It's only been the added weight and complexity that's limited its use. I got to see one of those Junkers WWII engines when I was in aircraft mechanics school back in the late Seventies.

 

[km1125]

Seems like you could get some pretty low deck heights with a pair of those instead of something like a pair of KT38's.

25% improvement in efficiency is pretty huge too... lots of range on a tank of fuel!

 

[DWABoat]

It seems really efficient, especially being a two stroke. But wait …if it goes domestic application, the climate gang will attach 700 lbs of emissions stuff on the intake and fuel feed side, mix in some air freshener to the fuel, two hundred sensors to control everything, computers to send digital emissions reports, and push its exhaust through four scrubbers and sprayed with engine driven DEF pumps. Gross torque: 700. Net torque to axle: 20.

 

[ttmott]

Well, interesting for sure. But…I thought the internal combustion engine was under the guillotine? Seems conflicting that domestic car manufacturers and fed gov will invest heavily in this new tech while simultaneously trying to dismantle the petroleum industry and ICE.

It seems really efficient, especially being a two stroke. But wait …if it goes domestic application, the climate gang will attach 700 lbs of emissions stuff on the intake and fuel feed side, mix in some air freshener to the fuel, two hundred sensors to control everything, computers to send digital emissions reports, and push its exhaust through four scrubbers and sprayed with engine driven DEF pumps. Gross torque: 700. Net torque to axle: 20.

Ya probably need to let it go. Diesel engines and diesel fuel will be here for the foreseeable future.
How about we just look at what cool tech this is....

 

[DWABoat]

Ya probably need to let it go. Diesel engines and diesel fuel will be here for the foreseeable future.
How about we just look at what cool tech this is....

Yea, you are right. I will behave! The first question I thought was legit. Wondering about the current state of the research since the video was from 2017. A lot has changed.

The second comment was complete sarcasm.

A serious question about the productive hp in practice. Since the two cylinders are moving away from each other, the expansion pressure creating the torque will be decreasing at twice the rate of a single cylinder engine. As such, given the same cubic inches, the “stroke” will be one half of a single piston type. It seems like the “work” produced by this engine, with very short stoke, would be similar to the big-block 351 Cleveland versus the small-block 351 Windsor comparison back in the day. The big blocks just have so much capacity to work instead of the little small block hamster on a treadmill.
Do you see that as a limitation in a real-world, heavy load application such as a large boat?

 

[ttmott]

Yea, you are right. I will behave! The first question I thought was legit. Wondering about the current state of the research since the video was from 2017. A lot has changed.

The second comment was complete sarcasm.

A serious question about the productive hp in practice. Since the two cylinders are moving away from each other, the expansion pressure creating the torque will be decreasing at twice the rate of a single cylinder engine. As such, given the same cubic inches, the “stroke” will be one half of a single piston type. It seems like the “work” produced by this engine, with very short stoke, would be similar to the big-block 351 Cleveland versus the small-block 351 Windsor comparison back in the day. The big blocks just have so much capacity to work instead of the little small block hamster on a treadmill.
Do you see that as a limitation in a real-world, heavy load application such as a large boat?

All good - I just picked up on the tech so I really don't know the work vs displacement. However, they did say the heat rejection was greatly reduced so the result must be work. Also, 1000 HP from 11 liters in military trim isn't incidental. For example the military version of the QSM 11 is rated at around 260 HP where the recreational boat form is 660 HP. Cummins, it seems, is in a joint venture with another developer and has contracts with the Gov for the engine. Three cylinders at 11 liters isn't peanuts so I'd expect based upon short strokes very large cylinder diameters - way out of square as we say.
For a boat application - I'm sure these are very wide in a horizontal configuration but possibly more applicable in a vertical application. In a vertical application however, the counter shaft that the gear needs to attach would be rather high. I guess, I see this more for large single screw boats like Nordhavn or Krogran or Grand Banks in a horizontal configuration. But - It's cool....

 

[blaster]

I want to put it in a Subaru. Perhaps some suspension modifications as well.

 

[Nater Potater]

A serious question about the productive hp in practice. Since the two cylinders are moving away from each other, the expansion pressure creating the torque will be decreasing at twice the rate of a single cylinder engine. As such, given the same cubic inches, the “stroke” will be one half of a single piston type.

Keep in mind that, for a given cylinder diameter, you've ingested twice the volume of air as a conventional engine. A three cylinder opposed is effectively a six cylinder engine.

For a boat application - I'm sure these are very wide in a horizontal configuration but possibly more applicable in a vertical application. In a vertical application however, the counter shaft that the gear needs to attach would be rather high.

The power can be pulled from either crankshaft or any of the timing gears in between. In a vertical application, running off what's now the lower crank would be no different from what we currently have.

 

[b_arrington]

All good - I just picked up on the tech so I really don't know the work vs displacement. However, they did say the heat rejection was greatly reduced so the result must be work. Also, 1000 HP from 11 liters in military trim isn't incidental. For example the military version of the QSM 11 is rated at around 260 HP where the recreational boat form is 660 HP. Cummins, it seems, is in a joint venture with another developer and has contracts with the Gov for the engine. Three cylinders at 11 liters isn't peanuts so I'd expect based upon short strokes very large cylinder diameters - way out of square as we say.
For a boat application - I'm sure these are very wide in a horizontal configuration but possibly more applicable in a vertical application. In a vertical application however, the counter shaft that the gear needs to attach would be rather high. I guess, I see this more for large single screw boats like Nordhavn or Krogran or Grand Banks in a horizontal configuration. But - It's cool....

This could be awesome in a single like my Back Cove. It has a single QSC 600 in it.

The bigger Back Cove 41 offers the QSM 11 in the 715 hp configuration and that’s the recreational version.

 

[Flyer5]

I want to put it in a Subaru. Perhaps some suspension modifications as well.

Subaru pistons are meant to run away from each other.

 

[Great lakes pirate]

I want to put it in a Subaru. Perhaps some suspension modifications as well.

 

[blaster]

Imagine buying a new Subaru and you are issued a tag with the first three characters LZB? Thats what happened to someone I know. They are okay cars but not my cup of tea. I still want to put that giant motor in one though.

 

[Carpediem44DB]

This technology will be neat to watch and see if it ever scales. It will be interesting to see if the sustainable fuel can ever scale as well and if so I can see this making sense to even the greenies. Diesel and new diesel like fuels are being touted as the future for aviation along with EV.