Build the perfect water cooled engine

[billswagger]

Its funny, because we can talk displacement and HP ratings, but actual performance of the plane seems to be where you end up putting the damn radiator.
under wing?
chin?
aft the pilot?

It would appear that aft the pilot offered the least drag to the air frame, but then its also more vulnerable to enemy fire.
Reason for keeping it on the chin may have been to keep all vulnerable parts in one area of the air frame.

Perhaps a part two of your question would be how to build a better cooling system?

 

[tomo pauk]

I'd like to propose a 12 cyl boxer, horizontal layout, with 30-35L capacity, a supercharger set as good as it gets for the era, with a provision for an engine-mounted cannon (laying above the crankshaft), with annular radiator. Cylinders/pistons dimensions akin to scaled-up Sabre parts (bore > stroke), for a good revvability. A twin-stroke would've been nice.

 

[Readie]

Pratt Whitney R-4360 Wasp Major Cutaway. I know its air cooled but, the powered cutaway is worth a peek
Cheers
John

 

[Lighthunmust]

.....how are you going to feed these monsters you're proposing? Wouldn't the massive fuel loads result in rapidly diminishing returns on over-all aircraft performance.

All the power you propose may increase climb rate, acceleration, and load carrying, but do nothing to knock down the mach wall of propeller tip speed and airframe design. How are you going to overcome those issues?

Aren't sleeve valves a dead-end for the following reasons:

"They subsequently fell from use due to advances in poppet-valve technology including sodium cooling and to their tendency to burn a lot of lubricating oil or to seize due to lack of it." -wikipedia

Complexity in manufacture, need for precision fit, and the effects of battle damage?

Contra-rotating propellers? Did anyone ever really get those right on a piston engined aircraft? I'm not saying they couldn't be made to work, just look at a Tu-95, but are they really worth the complexity and vulnerability?

 

[Readie]

I have been busy looking at most of the contenders for this title.
Its very difficult to choose the best from each as the engine is a collection of parts all of which make it whole.
I reckon that the RR Griffon ticks most of the boxes.Power - weight etc.
'What, not the Merlin?' I hear you cry...
Well...what can I say
Cheers
John

 

[tomo pauk]

Lighthunmust,
You can check out my proposal - nothing fancy in it

 

[fastmongrel]

If they could have got it to stay in one piece or not melt itself into a solid lump of aluminium the Rolls Royce Crecy .

Apparently it sounded like all the damned souls in hell screaming at once the pilot would have needed 2 pairs of earplugs to stop his brain melting.

 

[Lighthunmust]

If they could have got it to stay in one piece or not melt itself into a solid lump of aluminium the Rolls Royce Crecy .

Apparently it sounded like all the damned souls in hell screaming at once the pilot would have needed 2 pairs of earplugs to stop his brain melting.

Noise is definitely an issue with air and ground crew performance. The the noise of the turboprop version of the F-84 reportedly physically sickened people not just from engine noise but from propeller tip noise.

 

[Lighthunmust]

Lighthunmust,
You can check out my proposal - nothing fancy in it

Agreed nothing fancy. I was referring to the much more complex,larger, and powerful proposed monsters.

 

[Lighthunmust]

Pratt Whitney R-4360 Wasp Major Cutaway. I know its air cooled but, the powered cutaway is worth a peek
Cheers
John

Perhaps this may be the best starting point by creating a hybrid liquid cooling system for this engine. Maybe that would have helped with the overheating problems of the B-36.

 

[Readie]

If they could have got it to stay in one piece or not melt itself into a solid lump of aluminium the
View: https://www.youtube.com/watch?v=fZMPDCNyQxE
Cheers
John

 

[gjs238]

What could he have done for/with the 601-603-605 engines?!

 

[fastmongrel]

A bit like these?
The British Racing Motors V16 was a supercharged 1.5 litre (90.8 cu in) V-16 cylinder racing engine built by British Racing Motors (BRM) for competing in Formula One motor racing. Designed in 1947 and raced until 1954-55, it produced 600 bhp (450 kW) at 12,000 rpm, although test figures from Rolls-Royce suggested that the engine would be able to be run at up to 14,000rpm.

View: https://www.youtube.com/watch?v=fZMPDCNyQxE
Cheers
John

This is a proper car engine
View: https://www.youtube.com/watch?v=F2vNevKRAvk saw it spitting fire at the Liverpool festival of power the pulse of the engine made your chest vibrate

Napier Lion

 

[Readie]

This is a proper car engine
View: https://www.youtube.com/watch?v=F2vNevKRAvk saw it spitting fire at the Liverpool festival of power the pulse of the engine made your chest vibrate


View: https://www.youtube.com/watch?v=6O1fSfANxbM

View: https://www.youtube.com/watch?v=Ub0hwAPiidM

View: https://www.youtube.com/watch?v=JXS3GBRX1Ys

I love these...

The Germans have made some monster car with an old Maybach in it I think
Brutus

View: https://www.youtube.com/watch?v=zUsaYRyuGNY

V8 motorbikes etc I think that are all brilliant.

Sorry, got a bit carried away...
Cheers
John

 

[Shortround6]

Aren't sleeve valves a dead-end for the following reasons:

"They subsequently fell from use due to advances in poppet-valve technology including sodium cooling and to their tendency to burn a lot of lubricating oil or to seize due to lack of it." -wikipedia

Complexity in manufacture, need for precision fit, and the effects of battle damage?

Well, it is wikipedia
The Sleeve valve/poppet valve argument started back before 1930. Sodium cooled valves date from before 1930. ALL high powered aircraft engines (and quite a few not so high powered ones) used sodium cooled exhaust valves and few engines even used sodium cooled intake valves. Much better cylinder head finning and construction helped the valve and valve seat cooling.

The Sleeve valve/poppet valve argument started when 70 octane fuel was hot stuff and 6 to compression and even 1lb of boost was state of the art

Every time either side made a good stride forward somebody moved the goal post.

Sleeve valves were expensive to manufacture and by the time they really got them sorted out (post WW II) jets were taking over. Some of the post war Hercules and Centaurus engines posted some truly incredible times between overhauls.

 

[gjs238]

The DB supercharger arrangement seems to allow for a great deal of design flexibility.
Mounted off to the side, it seems that they are conducive to multi-stage, multi/variable speed configurations.
And the larger displacement engines didn't need as much boost to begin with.

The inverted arrangement seems to help with pilot visibility.
The motorcanon is a bonus.

Wonder how the P-51 and A-36 would have faired with DB power.

 

[Lighthunmust]

Well, it is wikipedia
The Sleeve valve/poppet valve argument started back before 1930. Sodium cooled valves date from before 1930. ALL high powered aircraft engines (and quite a few not so high powered ones) used sodium cooled exhaust valves and few engines even used sodium cooled intake valves. Much better cylinder head finning and construction helped the valve and valve seat cooling.

The Sleeve valve/poppet valve argument started when 70 octane fuel was hot stuff and 6 to compression and even 1lb of boost was state of the art

Every time either side made a good stride forward somebody moved the goal post.

Sleeve valves were expensive to manufacture and by the time they really got them sorted out (post WW II) jets were taking over. Some of the post war Hercules and Centaurus engines posted some truly incredible times between overhauls.

Until the books you recommended arrive you guys and wiki are my primary sources. So for engines that are going to get shot at is the expense and complexity of sleeve valves a bad idea? The few books I have that give small mention of them do not give the impression they were superior.

 

[Readie]

Well, it is wikipedia
The Sleeve valve/poppet valve argument started back before 1930. Sodium cooled valves date from before 1930. ALL high powered aircraft engines (and quite a few not so high powered ones) used sodium cooled exhaust valves and few engines even used sodium cooled intake valves. Much better cylinder head finning and construction helped the valve and valve seat cooling.

The Sleeve valve/poppet valve argument started when 70 octane fuel was hot stuff and 6 to compression and even 1lb of boost was state of the art

Every time either side made a good stride forward somebody moved the goal post.

Sleeve valves were expensive to manufacture and by the time they really got them sorted out (post WW II) jets were taking over. Some of the post war Hercules and Centaurus engines posted some truly incredible times between overhauls.

Sleeve valves were an engineering solution that worked well.One of the critical advantages was that the spark plug(s) could be place in the optimum position without valves getting in the way.
The high performance two stroke motorcycle engines had a sort of sleeve valve and they flew !
Cheers
John

 

[Shortround6]

I'd like to propose a 12 cyl boxer, horizontal layout, with 30-35L capacity, a supercharger set as good as it gets for the era, with a provision for an engine-mounted cannon (laying above the crankshaft), with annular radiator. Cylinders/pistons dimensions akin to scaled-up Sabre parts (bore > stroke), for a good revvability. A twin-stroke would've been nice.

If you are using an annular radiator then it doesn't much matter if the engine is flat or V or inverted V. In fact either of the V's is going to be narrower than a flat engine for better pilot visibility. A Napair Sabre was about 10in wider than Merlin or Griffon. using bigger cylinders would have only made it wider. Sabre already had a piston speed of 3084fpm compared to a Merlin's 3000fpm. a larger cylinder is going to mean lower revs than the original Sabre.
The big problem with a lot of these engine was keeping them cool enough to stay running. At 15lb of boost an 4 stroke engine is moving about the same amount of fuel and air as an EQUAL sized 2 stroke per minute with no super charger. Supercharging a 2 stroke means that much more heat being generated in the cylinder every minute. There may be some advantages but I wouldn't expect a big jump in performance.
You also need a supercharger that could keep up with it

 

[Readie]

Napier Deltic made a mild supercharged two stroke diesel for RN and Railway use, Powerful but, high maintaince.
I remember the locomotives, they had a very distinctive sound.
Cheers
John