Advantages of sleeve valves for H-24 engines?

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I copy pasted this into Google Translate and it said:

"I am too embarrassed to admit I made a mistake"
Funny, you could attribute those words to yourself, too - recall when you claimed no Sabre was type-tested at over +10lb boost?
Yet the evidence arose to prove that assumption - while based on what you'd gleaned to that point - was incorrect.
 
C'mon now, you def' hang your biases out here, & self-aware or not, that is inevitably going to present in selection/commentary by the author.
 
I didn't avoid mentioning it. The rating of 3050 hp is what Ricardo wrote in his book, as I quoted in post 111. I have never claimed the max power rating was anything other than 3050 hp.
I saw no reason to bring up E122, as it was never run.
Or was it? A wee while ago, a member linked a site to aircraft crashes in the UK, & one I looked at - noted a flight out of Luton, being a test
flight of an experimental Napier-powered aircraft, & listed the engine as a 'Sabre VIII' - ok it could've been a typo, but maybe not?
 
That is interesting. It wouldn't be the first time something has been emphatically denied, and then a document turns up to show it is true.

There would have been far more Napier documentation prior to RR getting involved. Some may exist out there that isn't in the Napier Heritage Trust or IMechE.
The book "By Precision into Power" lists more Sabre series engines than has been listed on this thread.

Edit: added 'been' to the first line to make it read better.
 
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Right, & these issues were encountered in an aircraft only recently introduced to service, & then pressed into vital defence duty.
Of course, the writer got it wrong about the likelihood of further boost increases, unless he meant real short term.

Check the site linked below, scroll down the combat reports to the end, and see the comment by Ron Dennis
(who'd run down an Me262 at max-boost "400mph IAS @ 0ft" for over 10min, to share the kill with his wing man)
about the sensitives of available propellors given the Sabres power (14ft prop - can you find a WWII fighter with a bigger one?)

 
When was that?
We`ll perhaps find out more, I`ve just asked the former chief designer.

Mercedes made a mad barrell valve F1 engine head once. It was never raced, it was shown in Race Engine Technology magazine a few years ago.

I was told informally that the reason it was all put in a magazine was that it wasnt viable, athough the FIA would also certainly have banned it
these days on cost grounds. F1 is a really bad place for major engine innovation now, doing anything very different costs the budget necessary to start
a small war in the 3rd world somewhere. Ditching the turbocompound for 2026 was stupid, but necessary to drop entry costs enough to get new
competitors to sign up (aledgedly, - I think the real reason is just to slowly start making the engine more and more rubbish and gradually
replace it with more and more of an electrified powertrain until one day someone says - "hey might as well not have the engine?"
at which point it will turn into Formula-E, so much for Ross Brawn reforming the FIA ! )
 
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A QUESTION...

We have seen in this forum, about a year ago (more or less...) , a very unusual graph comparing the main great engines of WWII. It integrated, as I remember, power, RPM and BMEP.

The Sabre was credited by 3.900 hp and the drawing showed that this was obviously "out or range".

I'm unable to find back this drawing. Any idea ? Thanks !
 
Here's one, (& hey, its right up your alley) - when Cosworth proposed an F1 sleeve valve mill, it was promptly kyboshed by the FIA!)

So my Cosworth contact says he never heard of any such engine, the thinking is that you have probably gotten very mixed up reading some forums,
and confused it with the rotary valve engine, which was he says actually done by Ilmor for Mercedes, and this is what was published in the magazine.

Its not a sleeve valve engine, and it was this which was banned by the FIA.

Incidentally you can find this exact valve layout in German aero engine publications from about 1938.


 
So my Cosworth contact says he never heard of any such engine

The wikipedia sleeve valve page has this to say:


However no references are given for this statement.
 
List them >
From "Short Stirling, The First of the RAF Heavy Bombers" written by Pino Lombardi 2015. Page 181 Paragraph 1. Trials were made with both the Hercules II and the Wright Cyclone (actually the GR-2600-A5B). The findings were the sleeve valve had the following advantages over the poppet valve.
(2) Performance
(3) Fuel Consumption
(4) Noise

This comparison is obviously the same aeroplane with the only change being the engines, which provides the only like-for-like real world comparison I have found.

I showed a comparison of the performance curves and bsfc in this thread:
 

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