33 replies to this topic

[Duckers]

Can anyone please tell me what the largest piston engines are (but not steam), like those in super tankers, etc? I would appreciate as much info as possible, like power, torque, dimensions and so on.

Thanks

Duckers

[desmo]

I feel a contest coming on!

Here's my first shot:

MAN B&W K98MC 2 Stroke CI 12 cylinder- Bore: 980mm Stroke: 2660mm Dry Weight 2146 tons 93,000bhp

[unrepentant lurker]

What's "largest" mean? Cubes or Horsepower?

[Rainer Nyberg]

Desmo, there is also an 14cylinder version of the MAN B&W K98MC.

108920 HP @ 84rpm

Weighs a hefty 2446 tons...

[LeTurc]

I dont know but, there are some you can walk in them.

[Ali_G]

What in god are they used for ?

What sort of capacity are we talking aobut for that engine.

Niall

[Jhope]

Those engines are used in the Shipping industry?!?!

[Rainer Nyberg]

Yes, supertankers.

[Duckers]

Unrepentant Lurker, the engines I'm after are largest in capacity and dimensions, but as Desmo and Rainer Nyberg have quoted 90000+ BHP for some then I suppose horsepower can come in to it as well.

[marion5drsn]

Go to ; http://www.fairbanks...com/pcengs.html
Not quite as big as the MAN but they are used for stationary
power plants, 18 cylinders and so forth.
I've been looking for MAN Gmbh but have no luck. How did you find It? M.L. Anderson

[Top Fuel F1]

I think this would be a little more interesting if it didn't leave the door open for the exteremly unique stuff. For instance some sea-going tugs have diesels with pistons the size of oil drums and you can slowly count the cylinder ignitions. A little more familiar engine would be the big Pratt&Whitney radial pusher 4360's (6 per plane) where the cylinders spiraled from one bank to the next. These were used on the B-36 Super Fortress bomber just after WW-II. The two B-36 engine configurations were:

PROPULSION:
Powerplant
(B-36B) six Pratt & Whitney R-4360-41 radial piston engines
(B-36J) six Pratt & Whitney R-4360-53 radial piston engines plus four
General Electric J47-19 turbojets
Thrust
(B-36B) 21,000 hp (15,660 kW)
(B-36J) 38,460 hp (17,004 kW) plus 20,800 lb (92.5 kN)

Some one asked that some qualification be put on what the question is being asked on this .ie what is meant by largest.
Also I'd like to know what the purpose is other than what desmo said about "a contest".

[desmo]

MAN Home Page

[david_martin]

Originally posted by Ali_G
What sort of capacity are we talking aobut[sic] for that engine.

Niall

As posted by Desmo - 12 cylinder- Bore: 980mm Stroke: 2660mm. You are a resourceful chap, do the maths yourself.

[Darren Galpin]

Pi*radius^2 to get area of circle.

So, (980/2)^2*Pi*2660=2006428413mm cubed.

Divide by 1 billion to give 2 cubic metres per cylinder.

So, 24 cubic metres! (I think....)

[Pioneer]

For the metric challenged, thats 1,469,277 cubic inches.

[Croaky]

I get 5 litres per cylinder. But I can't count, so it doesn't really matter...

[Darren Galpin]

Remember that a litre is a 1000cm cubed, i.e. 100mmx100mmx100mm. There are 1000 litres in a cubic metre. And if the bore is almost a metre wide and just over 2 and a half metres tall, you can fit more than five litres - you could fit yourself!

[desmo]

I don't recommend it though!

[Croaky]

Hmmmm, I think you'd be safer trying to stuff yourself into a 5 litre cylinder than a 2 cubic metre one...
I did realize that 5 litres was a tad on the low side.
I definitely got 5 somethings rather than 2 somethings though. Damn those SI units

[buddyt]

....Just remember size doesn't matter.....;)

[MrAerodynamicist]

Whats the largest ever engine used in a wheeled (non-track) vehice?

[desmo]

Good question. The largest I could quickly find is the Cummins QSK78 engine for mining vehicles. 78l with 18 cylinders and 12 turbos. There's surely something much larger out there, even discounting the Saturn launch platform or other such railed vehicles.

[Pioneer]

IIRC, the launch platform vehicles are all electric.

[david_martin]

Originally posted by desmo
Good question. The largest I could quickly find is the Cummins QSK78 engine for mining vehicles. 78l with 18 cylinders and 12 turbos. There's surely something much larger out there, even discounting the Saturn launch platform or other such railed vehicles.

MTU have announced a new 20 cylinder version of their 4000 series engine (also for mining trucks), which will be 89.8 litres in capacity and produce a whopping 2700 kW!

[FlagMan]

How about the largest engine in a racing car?

Anyone know of anything to beat the Napier Railton Special - 24 ltr Y12.

[Janzen]

Sorry if I get off thr topic slightly but what would be the most powerful engine in comparison to its own weight. Would that be a F1 engine or maybe some Bike engines or what about dragsters ?

[Pioneer]

Assuming you mean something that burns gasoline, it would almost certainly be something very very small and 2-stroke no doubt.

Small electric motors are even more efficient per weight, but thats different.

[unrepentant lurker]

On a weight to power ratio, ramjets are impressive. The tradeoff is that you have to operate them in a rather narrow environement.

[marion5drsn]

According to the Guinness Book of World Records the largest piston engined race car was Jim Lytle's "Quad Al". Two Allison 4320s, or four V-1710s in and "X" configuration. 48 cylinders 141 liters or 6840 cubic inches, 192 valves,96 sparkplugs. Engine was developed for the big bombers of WW-2. See,"Vee's For Victory" Chapter 14, Pages 282 to 315. M.L. Anderson
.

[leegle]

Also off topic - Has anyone ever tried to make a diesel engine work for aircraft? Seams to me that this would have been a good way to go for long range air transport before jets came in. There is a bit in the Nostalgia forum about a diesel at Indy.

[desmo]

The ultimate development of the compression ignition aircraft engine is surely the Napier Nomad. Here's a short article on it:

Nomad Article

There's a fair bit about the engine on the web, it's been discussed here before too.

[desmo]

Here's a copy of a post I did on the Nomad a while back:





Here's some stuff on the incredible Nomad engine. I found a snippet of text from LJK Setright's book which I have included in this post. The first time I saw this cutaway illustration in a book from the local library, I'm pretty sure my jaw literally dropped.

From 'Some Unusual Engines', LJK Setright, ISBN 0852982089
>
>
> On the other hand, a far more thorough (if not to say brilliant)
> exploitation of compounding principles by Napier enjoyed no
> success at all: their Nomad engine, conceived at a time when
> propellors were expected to be the normal means of airliner
> propulsion, did not mature until the aviation world had gone over to
> jets. Like so many unusual engines, it arrived too late ; and to be
> truthful it may be argued that it never really matured anyway, since
> it was by all accounts a pig to start.
>
> Looking at its specification, this hardly seems surprising. The
> Nomad was a 12 cylinder horizontally-opposed liqid cooled two-
> stroke compression-ignition engine cmpounded with an exhaust
> gas turbine, both of these units driving a single propellor shaft
> through reduction gears. Even the basic construction was
> satisfying: the crankcase was a two-piece structure of magnesium
> alloy castings, the two cylinder blocks were of aluminium alloy with
> dry liners fitted in each cylinder bore. Each of the cylinders had its
> own aluminium cylinder head, elegant and simple in shape
> because the 8 inlet and three exhaust ports of each cylinder were
> of course in the walls.
>
> As appropriate to a 2-stroke the the ratio of bore to stroke was
> unfashionably low, resulting in measurements of 6 and 7.375
> inches respectively. This yielded a displacement of 2505 cubic
> inches, (41.2 litres), making a fairly big engine thet weighed
> 3580lb. Beneath and behind the crankcase was the turbine
> department, where a three-stage axial flow turbine rotor was
> mounted on a shaft which drove through a variable-ratio Bair fluid
> coupling and gearing which connected it to the propellor shaft -
> which in turn conected through reduction gears to the crankshaft.
> Coupled ot the turbine shaft was the compressor, a twelve stage
> axial flow affair delivering air to the cylinders at very high pressure
> (8.25 atmospheres) and in enormous quantities (13 lb/sec at
> maximum speed)
>
> Many an engine of much less complication has been debased by
> some want of efficiency in one of more of its component elements.
> It is a tribute to the design of the Nomad that,
> with so many constituent sections that could
> have let it down , it was in fact of
> extraordinary efficiency. The whole operating
> cycle was designed to extract every possible
> quantum of energy: nothing was allowed to to be
> wasted at any stage. After combustion was
> initiated by the injection of diesel fuel into
> the cylinders, the initial expansion of the charge would deliver
> power through the pistons to the crankshaft. As soon as the
> exhaust ports were uncovered expansion would continue through
> the exhaust manifold to the turbine, where the gasses and residual
> hot air produced by combustion would liberate more power for
> transmission through the hydraulic coupling to the propellor shaft.
> The total power from the crankshaft and turbine was considerable,
> and with water injection the take-off rating was 3476hp at 2050
> rev/min. But there was more to come: there as still a little energy
> left in the exhaust gasses even after negotiating the turbine, and
> this was squirted out as a jet at the back to produce a further
> 250lbs of thrust, maing a total equivalent horspower of 3570.
>
> This was equivalent to a BMEP of 205 psi, a very high figure for a 2-
> stroke. The other specific performance factors were no less
> impressive: the engine weighed virtually one pound per horsepower
> and developed 10.5 hp for every square inch of piston area - which
> provides a revealing comparison with the 6.58 hp.in^2 of the Wright
> Turbo Compound. At maximum continuous rating the Nomad
> developed 2248 equivalent horsepower, ; but looming overall was an
> incomparably mean specific fuel consumption. The engine had after
> all been concieved as the propulsive unit for a really long range
> aircraft, intended to realise the most outstanding economy. Napier
> claimed 0.33 lb/hp.hour, although Air Vice Marshal Banks has
> hinted that it never quite achieved that.
>
> It was nevertheless a most satisfying performance. Napier were not
> to be satisfied though, for thay argued that it ought to be possible
> to do something with the unburned air in the exhaust system. A
> diesel can only burn 70% of the air it breathes: they therefore
> inserted an afterburner nozzle in the exhaust manifold, injecting
> extra fuel to burn the remaining oxygen and thus allow the the
> turbine to make a much greater contribution to engine output.
>
> This and an intercooler betwen the the compressor and the
> cylinders added a mere 170lb to the total weight of the engine; but
> the result of this slight investment was a fantastic profit of no less
> than 530hp. On this basis the specific weight fell to 0.83 lb/hp -
> and who would have though that any diesel would have proved to be
> relatively lighter than the majority of spark-ignition engines gulping
> relatively larger quantitis of the best quality petrol?

[Duckers]

Desmo that Nomad is some mean engine! I've often wondered if it was possible to combine a piston and gas turbine into a compound engine.

Before I gained more knowledge on Motorsport/Automotive Engineering I even thought it would be possible to use a similar engine in F1, even though now I'd very much doubt it would work as the regulations are too restrictive, plus weight and relability issues.

Duckers

[marion5drsn]

The first succesful compound piston engine that I know of is the R-3350 Curtiss-Wright Turbo-Compound engine of the Lockheed Constellation of about 1946. This was a development of the B-29 R-3350 of WW-2. A very troublesome engine. This engine was the reason that the X-3420 engine of Allison development.
It was for the bombers of WW-2. The Constellation was one of the great commercial aircraft of that time. Only not too well recognized because of the arrival of jet aircraft. M.L. Anderson