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 12/05/2008, 10:31 PM
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keith gerrard
 
Joined on 16/04/2004
Posts 9,870
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12/05/2008, 10:40 PM
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Jill
Joined on 15/08/2005
Norfolk
Posts 1,791
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Dont get upset for Keith, Lionheart
You win a few, you lose a few
Nobody minds, especially Keith
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13/05/2008, 12:31 PM
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keith gerrard
Joined on 16/04/2004
Posts 9,870
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The above aircraft is the Hawker Sea Fury we had at Elstree Harry.
Owned by my late friend Spencer Flack and test flown by Neil Williams (who died in an He 111 in Spain, ex Red Arrows CO).
Originally cartridge start, we converted it to GPU using Beverly ring gear components.
The engine is a radial Bristol Taunus of 2800 hp using sleeve valves similar to the Napier Saber.
The Saber in the Hawker Typhoon and later Tempest (laminar flow wing), was an in-line water cooled sleeve valve engine that was subject to rear cylinder over heating and sometimes caught fire. The later Sea Fury was a radial air cooled sleeve valve engine with even cooling of all cylinders. This aircraft ran out of hydraulics landing at Elstree and the undercarriage had to be pulled up which allowed it to end up 25 feet from a power station near the end of 09. I remember it well.
For nevermind, the aircraft was ex Luftwaffe and used by them as a target tug.
Spencer died in a racing accident in Australia.
Tony Rudd had projected the idea for an H16 Sleeve valved engine for BRM in the 1950,s but it was not until the 60,s when he took over as Technical Director that the H16 format was introduced, using conventional valving because of the rear cylinder heat problem, which had not been solved for sleeve valves in in-line engines. In the 50,s BRM used the V16 of 1.5 Liters supercharged.
Tony's H16 went on to win in America in a Lotus before the introduction of the Keith Duckworth designed DFV from Cosworth.
IMO the cost of designing and building an F1 engine had increased to such a huge figure by the late sixties, it made it impossible for any but the biggest vehicle companies to chase the performance figures of the DFV. Unlike today there were not the commercial monopolies to ensure long term success through guaranteed on going development. Keith Duckworth and Colin were geniuses it is true but they were also in the right place at the right time.
I talked with Tony on a number of occasions about the possibility of a sleeve valved F1 engine and other types of rotating sleeve valving and rotating valves as used in the cross engine etc. It was always a cost issue that prevented development.
Desdramonic valves (forget the spelling) have been the only departure from conventional poppet valves in F1, apart from the hydraulic and pneumatic valve spring systems to prevent bounce.
Dream on keithgerrard@gerrard24.freeserve.co.uk
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13/05/2008, 12:38 PM
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Harry Remmington Mk II
Joined on 26/06/2007
Posts 397
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 keith gerrard wrote: | | ....but it was not until the 60,s when he took over as Technical Director that the H16 format was introduced |
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Which was the point I made originally.
Harry
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13/05/2008, 1:02 PM
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keith gerrard
Joined on 16/04/2004
Posts 9,870
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Yes Harry but Tony had been developing the design for years before it raced.
You state the DFV as the death of BRM but there was much more to it than that.
Tony moving to Lotus was no small part of the collapse and his work with Keith Duckworth (as technical director of Lotus), in no small part ensured the success of both Cosworth and Lotus.
In those days they all knew one another and new ideas were the way forward.
Today it is just snotty nosed graduates on computers fine tuning things that have not changed for years.
I remember sitting in my office at Aldenham Automatics discussing the Lotus 88 twin chassis car with Tony and his views on ground effects and computer control. The twin chassis car was the ultimate application of GE's. The separate mechanical suspended chassis allowing full ride and mechanical handling adjustment, without upsetting the exact ride height of the second GE chassis body assembly.
It was banned of course!!! Things had changed.
Dream on keithgerrard@gerrard24.freeserve.co.uk
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13/05/2008, 1:58 PM
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C C
Joined on 21/08/2003
Posts 1,250
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| keith gerrard wrote: | |
Today it is just snotty nosed graduates on computers fine tuning things that have not changed for years.
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Everything was always better in the good old days.
It's true there is little scope for innovation in F1 cars today because the cars are simply too fast. The challenge for those snotty nosed graduates on computers is to fine tune ways around whatever technical restrictions the FIA impose.
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13/05/2008, 3:10 PM
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keith gerrard
Joined on 16/04/2004
Posts 9,870
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The cars are no faster than they were pre war CC.
The circuit designs of today, limit the top speed to around 200mph max.
All the F1 cars of the 1930,s were capable of this speed if geared for it.
It is the acceleration, cornering and braking that have improved by huge amounts.
Driving F1 in the 30,s was for men, today it is for athletes with fast reflexes.
The danger involved has all but been eliminated.
Yes snotty nosed graduates are there to fight the regulations with fine tuning of things that have existed for decades.
I have seen them design components that the guys on the shop floor could not even get the bolts in!
IMO technological genius died around the time of the Concorde's death.
Give me enough money and I will create you a winning F1 team in two Months.
It would bore me to death though.
Dream on keithgerrard@gerrard24.freeserve.co.uk
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13/05/2008, 3:39 PM
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Equitator
Joined on 04/11/2003
Posts 1,001
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| keith gerrard wrote: | |
The above aircraft is the Hawker Sea Fury we had at Elstree Harry.
Owned by my late friend Spencer Flack and test flown by Neil Williams (who died in an He 111 in Spain, ex Red Arrows CO).
Originally cartridge start, we converted it to GPU using Beverly ring gear components.
The engine is a radial Bristol Taunus of 2800 hp using sleeve valves similar to the Napier Saber.
The Saber in the Hawker Typhoon and later Tempest (laminar flow wing), was an in-line water cooled sleeve valve engine that was subject to rear cylinder over heating and sometimes caught fire. The later Sea Fury was a radial air cooled sleeve valve engine with even cooling of all cylinders. This aircraft ran out of hydraulics landing at Elstree and the undercarriage had to be pulled up which allowed it to end up 25 feet from a power station near the end of 09. I remember it well.
For nevermind, the aircraft was ex Luftwaffe and used by them as a target tug.
Spencer died in a racing accident in Australia.
Tony Rudd had projected the idea for an H16 Sleeve valved engine for BRM in the 1950,s but it was not until the 60,s when he took over as Technical Director that the H16 format was introduced, using conventional valving because of the rear cylinder heat problem, which had not been solved for sleeve valves in in-line engines. In the 50,s BRM used the V16 of 1.5 Liters supercharged.
Tony's H16 went on to win in America in a Lotus before the introduction of the Keith Duckworth designed DFV from Cosworth.
IMO the cost of designing and building an F1 engine had increased to such a huge figure by the late sixties, it made it impossible for any but the biggest vehicle companies to chase the performance figures of the DFV. Unlike today there were not the commercial monopolies to ensure long term success through guaranteed on going development. Keith Duckworth and Colin were geniuses it is true but they were also in the right place at the right time.
I talked with Tony on a number of occasions about the possibility of a sleeve valved F1 engine and other types of rotating sleeve valving and rotating valves as used in the cross engine etc. It was always a cost issue that prevented development.
Desdramonic valves (forget the spelling) have been the only departure from conventional poppet valves in F1, apart from the hydraulic and pneumatic valve spring systems to prevent bounce.
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Desmodromic – for the record.
Here’s a demo:
http://www.ducatidesmo.com/valves.htm
Were anybody to ask me to design a valve system ab initio – not that they would – this would be my first approach rather than sodding about with bouncy springs.
Equitator
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13/05/2008, 4:30 PM
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keith gerrard
Joined on 16/04/2004
Posts 9,870
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Above is a transmission design I discussed with the Honda MC team for an automatic/semi automatic seven speed bike.
It forms the basis from a complete F1 transmission package that sits awaiting development funds at Hewland Engineering.
The pulse electronics for the EMU for torque shifting was as used in the Ducati as a compromise using their manual box.
It has no need for a clutch or lay shaft and in top gear has zero torque loss.
It allows a complete re design of the control systems and ergonomic layout for the bike.
(i.e no levers on the bars, push button shift and front plus rear brakes on the pedals resulting in far better control over the machine).
Of course such developments on racing bikes is unlikely, as it would be banned by vested interest just like all other bike innovation outside Japan.
The desmo system of valve control was used in the Lambo F1 engine with some success.
If you look at your link animation on the system however, you will see that it still requires a hair spring to ensure valve seat pressure for sealing.
This spring is still subject to harmonic vibration at high operating speed (high revs) and both the Ducati and the Lambo engines suffer from gas blow by and early valve seat damage because of this. The hair springs are also not very robust and are subject to easy breakage.
I have monitored test engines on the dyno with see through combustion areas and watched the detrimental effect on flame travel and thermal efficiency using desmo valve systems. There is an interaction between floating (conventional valving) and the flow of gasses, that is less smooth with desmo valves.
They are complex to get right but can be better than poppet valves in some cases. Reliability is the sticking point.
Dream on keithgerrard@gerrard24.freeserve.co.uk
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14/05/2008, 1:55 AM
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Equitator
Joined on 04/11/2003
Posts 1,001
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“I have monitored test engines on the dyno with see through combustion areas and watched the detrimental effect on flame travel and thermal efficiency using desmo valve systems. There is an interaction between floating (conventional valving) and the flow of gasses, that is less smooth with desmo valves.”
Is it possible to get out comparative indicator diagrams for the two systems?
Equitator
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14/05/2008, 3:38 AM
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keith gerrard
Joined on 16/04/2004
Posts 9,870
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I do not know if such direct comparison data has been drawn up equitator, I have no such.
The tests undertaken covered a great deal of other data concerning gas flow and flame travel.
The main purpose was to establish best combinations to achieve high thermal efficiency at high revs.
Desmo valves were dropped as an option in this case on reliability grounds.
Development from the testing went towards pneumatic valve closing and variable port lengths, which may give you a clue as to which company was involved and the era the tests were undertaken in.
I was involved more on the transmission side and not directly on the engine development.
There is little noticeable difference between spring and cam controlled valve closing up to around 8,000 rpm as long as both types are light enough. Above this Desmo valve control works better for a sport engine with a relatively wide power band. The choice is based on cost and marketing needs and is less of an engineering decision. Ducati used Desmo valves in relatively high reving small capacity road bikes to gain a slight performance benefit but mainly to establish a selling point for their product. Of course they continued Desmo development into racing bikes and larger road bikes to maintain their market position and reputation for engineering excellence.
Desmo valve control is not better than pneumatic valve control in engines designed to work mainly at very high rpm (F1) and it is prone to far more reliability problems in this application, mainly because of the higher number of fast moving parts and the hair springs.
The ultimate poppet valve control system, is one that both opens and closes the valves using computer controlled hydraulics.
Such a system can have fully variable valve timing, lift and duration.
If I had the money I would develop one.
Sleeve or rotary valves still fascinate me however, the trouble is they are so costly to develop and reciprocating IC engines have remained stagnant in such real development areas for years now because of this. The big companies like to stay on established technology, as it would cost them a fortune to change production set ups for such radical change and the public accept what is given them without question these days anyway.
Dream on keithgerrard@gerrard24.freeserve.co.uk
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15/05/2008, 2:14 PM
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keith gerrard
Joined on 16/04/2004
Posts 9,870
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15/05/2008, 2:17 PM
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keith gerrard
Joined on 16/04/2004
Posts 9,870
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16/05/2008, 3:55 AM
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Equitator
Joined on 04/11/2003
Posts 1,001
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"Desmo valve control is not better than pneumatic valve control in engines designed to work mainly at very high rpm (F1) and it is prone to far more reliability problems in this application, mainly because of the higher number of fast moving parts and the hair springs.
The ultimate poppet valve control system, is one that both opens and closes the valves using computer controlled hydraulics.
Such a system can have fully variable valve timing, lift and duration."
So it appears cam operated desmodromic technology has peaked, at least in regard to high revving engines (although it could still be said that computer controlled hydraulically operated valves still fall within the etymology!).
Equitator
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