Hawkeye,
no doubt the mods will be along to tell me waht I did wrong
try this
www.ame.arizona.edu/ame412a/ame412.projects.F02.ht...a
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Well the tinyurl link worked for me earlier, but not now it would appear.
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DD,
there seems to be some problem associated with tinyurl, similar problems on (ahem) another site.
FiF
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FiF,
The tinyurl link you posted is working again now. Site must have been temporarily down for manitenance or something.
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FiF,
I tried to find the 1968 patent that is said to be behind the Jonovo engine as this would disclose the full workings, however the USPTO doesn't have a full search facility for patents of that age and I was unable to locate it in the half-hour I spent looking. The drawing is a typical patent drawing so I assume it comes from the original Jonovo patent.
I can't recall seeing this particular design before but hundreds of rotary engine designs have been patented over the years and I can think of only one, the Wankel, that has proved itself.
Like yourself, I can only guess as to how the Jonovo engine is supposed to work -- I say "supposed" because it obviously hasn't been built and tested and will almost certainly have all sorts of unsolvable problems.
It looks as though it has only one 'piston' (rotor tip), though there may be others in series, perhaps three at 60 degrees to one another. The "unique combustion chamber" appears to be very poorly shaped for effective fuel/air mixing. The "only three moving parts" appear to be the rotor complete with output shaft, an upper rotary valve and a lower rotary valve, the latter perhaps forming part of the combustion chamber during its rotational cycle.
The team mention that they plan to incorporate "current technologies like internal compression" -- this makes me wonder if they know anything at all about engine design. I also note that they plan to build the engine to run on compressed air, then convert it to run on gasoline and then convert again to burn hydrogen; I think they will be wasting their time in such a contorted development process and the only possible future for the design might be as an air compressor, albeit still with the well-known problems in this type of construction to overcome, like rotor tip wear and rotary valve friction (though these will be less pronounced in an air compressor than in a combustion engine).
It is fairly common for new engine designs to be submitted to engine manufacturers by university project teams under the guidance of mentors but the ones I saw always had very fundamental flaws. I'm not being highly critical of this; modern engine designs are very complex and it requires huge experience and talent, plus access to very high-tech facilities, to produce a viable design. If coming up with (unworkable) designs helps university students to free-think and practice problem-solving, then I suppose there's no harm done. I just wish they'd keep their fantasies to themselves!
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I looked at this and decided fairly quickly that it had the hallmarks of a student project, overreaching themselves in the enthusiasm of having discovered a potential goldmine waiting to be mined! However I expect they will gain valuable experience in realism, which may not be a bad thing in its own right. And if properly documented it will be the journey and not the destination that counts.
However if they get it right and everything goes to plan they will become very rich and I will remain poor!
pmh (was peter)
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i have found the patent and a bunch of other Jonova designe patents any one intersted email me.
also i think i know how it works .
waiting for a reply.
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Forgive the cynicism but I am suspicious of any machine that is supposed to tame fossil fuel and produce useable power with only "3 moving parts". The gas turbine was highly thought of 40 years ago with only 1 moving part. Forget about the ancillaries etc.
Oh, and I like the "we will then convert the engine to burn hydrogen" bit at the end. They make it sound like an afternoon's work over a cup of tea. I am not an engineer but I can detect the whiff of student over-optimism. I just can't see it ever making it beyond an AutoCAD project.
Hawkeye
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Stranger in a strange land
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Found the patent using the GB site.
try l2.espacenet.com/espacenet/bnsviewer?CY=gb&LG=en&D...+
Haven't had time to read through it yet, should be an interesting read tho :-)
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Perhaps I should have tried Espacenet. I used to study Espace CD-ROMs every month to see if there were any new patent applications that might affect our company, however they covered only European patents in those days.
In total (whole world) there were about 7000 new patent applications per month in my field of work alone! Each month would bring forth rotary engine designs without fail. There is an awful lot of people out there wasting an awful lot of money on patenting unrealistic designs.
Incidentally, did no-one spot my deliberate mistake? I mentioned that there might be three rotor tips at 60 degree spacing but I meant 120 degree spacing of course, otherwise there would be quite severe out-of-balance forces to be handled.
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The magazine news item which caught my eye is posted below. I should have done this before but too busy or just plain lazy, sorry.
Oct 2003 issue Materials Performance
"Engine combines Characteristics of Rotary and Internal Combustion Technologies
M.V.Veazey
Five undergraduate mechanical engineering students at the University of Arizona (Tucson, Arizona) recently announced that they have designed and built an engine with only two moving parts that incorporates the best features of rotary and internal combustion engines. The design of the four-part prototype "Jonova Motor" allows it to run reliably, efficiently and very smoothly, say the students.
The motor uses a rotary compression system that replaces the pistons, connecting rods and valves found in internal combustion engines. The rotors travel in a steady circular path- eliminating the jerky and variable motion of pistons- and are attached to a drive shaft. The students contend that the manner in which the rotors spin allows the motor to produce more power from a given amount of fuel than an internal combustion engine."
Personally I thought Dizzy summed it up very fairly but lets take the above on face value. Maybe at one specific speed and power output it might operate efficiently, but at the range of power and speed outputs required of almost all engines, except perhaps particular applications of stationary engines. Looking at shape of combustion chambers I seriously doubt decent emission performance. Only two moving parts? Obviously the rotor tip sealing issues are going to be interesting!!
Putting on my not so serious head a couple of things made me smile and of course this could be down to the students or the journalist.
"Jerky and variable motion of pistons" made me sympathise with the comment questioning if these guys really understood how engines work.
Also the comparison with the fuel consumption of "an internal combustion engine" made me wonder that what this device is if not an internal combustion engine, albeit a different concept from the Otto cycle giving just one example.
pedant mode = off.
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Whilst on the subject of oddball engine designs, What do the B.R. make of this design. I can`t see how it could perform as an engine, but possibly could have applications as a power source to drive a pump perhaps ???
michael.abendschoen.bei.t-online.de/stelzer.html
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Never come across that one. If you connected the reciprocating bits to a crank, you would have something akin to a boxer 2-stroke.
Now, how about something that my physiscs teacher swore was going to make the reciprocating piston engine obsolete?
www.geocities.com/kiwiengineer2002/orbital.html
Hawkeye
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Stranger in a strange land
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Seems to remind me of the ww1 aircraft engines! where the engine and the propeller revolved around a stationary crankshaft.
Or is my befuddled thinking showing my age.
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Nothing wrong with your memory, xam. I have a 1966 Science Museum booklet called Power to Fly which describes a rotary aero-engine with revolving cylinders and crankcase made by Laurent Seguin in 1907. It says that derivatives of this engine dominated the engine field for a while.
These engines were difficult to control and smelled of castor oil which was usually "distributed with impartiality over pilot and plane"! They were reliable for their day with a good power-to-weight ratio, however by about 1920 the increased size that became necessary for greater power "gave rise to a train of troubles not the least being the deleterious gyroscopic effects of the whirling cylinders on the manoeuverability of the planes they powered ... and it faded from the aeronautical scene".
The same booklet also describes the (non-rotary) Antoinette engine which powered the first British military airship Nulli Secundus in 1907 and was then transferred to power S.F.Cody's aeroplane in 1908, this being the first aeroplane to fly in England. The engine, which developed 50 hp at 1100 rpm and weighed about 210 lb, was a petrol-injected V8!
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a train of troubles not the least being the deleterious gyroscopic effects of the whirling cylinders on the manoeuverability of the planes they powered
The Sopwith Camel had such an engine, and legend has it that if the pilot wanted to bank 90 degrees to port then it was easier and quicker to bank 270 degrees to starboard.
It may have been the other way round, but the point still applies.
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what about a swashplate engine
en.wikipedia.org/wiki/Swashplate_engine
these have been used in torpedo's for years
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