Inventor of the Rotary and Radial engines

[leo]

Forumites:
Does anyone know who is responsible for the development of the rotary engine? I presume it wes developed solely for use in aircraft. I heard an ad for Black History Month which credited an unmamed black man for the invention.

Who first developed the radial engine? I know the British and French were fitting them to airplanes which would have been produced in 1918-1919.

Thank you:


leo

Two preliminary items. Per the USAF Museum: A Mr. F. O. Farwell developed a rotary engine in the US in 1896. His race was not mentioned.
The French and British-built Anzani 10 was an air-cooled radial engine of 90-100 horsepower. It was installed in the French-produced Caudron G.3 and later the Caudron G.4 twin-engine airplane which appeared in March 1915. By the time the U.S. began sending men to France to learn to fly in 1917, Caudron G.4s were being used for training purposes.
It's a start...

In the 3 books I have on rotaries none go back any further than the Sequins producing the first succesful aviation rotory, the 50 horse Gnome in 1908. Some mention is made of their use in boating prior to aviation use.

I have always wondered--the rotation of the cylinders is said to have aided in their cooling, but isn't one cylinder just traveling in the vacuum created by the cylinder in front of it?

Regards,
Steve

One would have to be very bold, or have a Cray and some rocking CFD software to try and predict airflow patterns around a series of finned, rotating cylinders that also happen to be partly cowled and oh yeah, translating forward at the same time.

Still, you can definitely say that cylinders are not traveling in a vacuum, that would be impossible. The only thing I'd be willing to say is that each cylinder would probably create a relatively weak (due to turbulence) low pressure zone on the trailing side of its motion.

As far as I know, overheating problems were caused more by poor lubrication than insufficient cooling air.

The concept of Cavitation, wherein the movement of the body thru the medium causes a partial vacuum across the trailing suface of the body, is move valid when the medium is funtionaly non-compressable, such as water. Air will flow more readily, and while there will be a delta P between the obverse and reverse sides of the cylinder, there will not be enough to cause a vacuum. The radial engine preceeded the rotary engine, but cooling problems prevented further development.There is a cursory overview of the Gnome Monosoupape at the Wright-Pat museum site, and you might find further hits by using "Anzani Clerget Oberuesel LeRhone Gnome"

It is generally accepted that the first successful rotary aero engine was the seven-cylinder Gnome 50hp of 1908. This engine had the unusual feature of having the inlet valve in the crown of the piston, fuel being supplied through the crankcase, almost in the fashion of early two strokes, relying on crankcase compression for delivery up the bore.

The success of the Gnome, and so of the concept of rotary engines, was that it was relatively light and provided a good power output for the time. It was soon followed by the le Rhone nine cylinder and one of the most successful rotaries of all time, the Clerget 9b-9j series (without which WO Bentley would never have achieved his fame, for the Bentley BR1 was simply a development of the Clerget commissioned by the Admiralty).

I'm not going to say that it was the first radial, but certainly one of the first successful radials was the ABC Radial made by the engines division of Sopwith Aviation. Problem was, the airframe it first went into was not a success therefore, by association, the engine was not a commercial success either. In any case, the war was close to its end by the time the ABC had completed proving trials and, of course, once the Armistice was signed, development stopped (which is what virtually bankrupted Sopwith).

Three problems plagued rotary engines - torque thrash (caused by the gyroscopic forces of the mass rotation), turbulence drag and the high oil consumption of total-loss lubrication.

I wrote an article entitled "Riley's Venture Into Aviation", published in the Automotive History Review of the Society of Automotive Historians (US) last year. It covers an ingenious alternative to the rotary, patented in August 1914 (!). I sent a PDF copy of that article to The Aerodrome which may be accessible to you (I don't quite know how - is this an opportune moment for The Aerodrome to set up an accessible Library?), but if not, I'd be happy to email you the same document.

It is generally accepted that the first successful rotary aero engine was the seven-cylinder Gnome 50hp of 1908. This engine had the unusual feature of having the inlet valve in the crown of the piston, fuel being supplied through the crankcase, almost in the fashion of early two strokes, relying on crankcase compression for delivery up the bore. The success of the Gnome, and so of the concept of rotary engines, was that it was relatively light and provided a good power output for the time. It was soon followed by the le Rhone nine cylinder and one of the most successful rotaries of all time, the Clerget 9b-9j series (without which WO Bentley would never have achieved his fame, for the Bentley BR1 was simply a development of the Clerget commissioned by the Admiralty). I'm not going to say that it was the first radial, but certainly one of the first successful radials was the ABC Radial made by the engines division of Sopwith Aviation. Problem was, the airframe it first went into was not a success therefore, by association, the engine was not a commercial success either. In any case, the war was close to its end by the time the ABC had completed proving trials and, of course, once the Armistice was signed, development stopped (which is what virtually bankrupted Sopwith). Three problems plagued rotary engines - torque thrash (caused by the gyroscopic forces of the mass rotation), turbulence drag and the high oil consumption of total-loss lubrication. I wrote an article entitled "Riley's Venture Into Aviation", published in the Automotive History Review of the Society of Automotive Historians (US) last year. It covers an ingenious alternative to the rotary, patented in August 1914 (!). I sent a PDF copy of that article to The Aerodrome which may be accessible to you (I don't quite know how - is this an opportune moment for The Aerodrome to set up an accessible Library?), but if not, I'd be happy to email you the same document.

During my researches I came across a reference to a compressed-air rotary engine designed and built in Australia in the late 19th century. For some reason the name Hargreaves suggests itself...

I trust that the good doctor, in his previous post, wasn't referring to the Dragonfly and Wasp radial engines produced by the ABC company as "successful." They suffered from chronic design and manufacture problems and never delivered the promised performance. Given that the RAF's 1919 fighter program was to a large degree dependent on the ABC engines, it's just as well the war ended when it did.

Whoops! Guess 'vacuum' wasn't a good term to use with you tech types. I didn't really mean a total vacuum! guess what I meant--was there actually that much cooling gained thru the rotation? Thanks.

Regards,
Steve

[Brad]

The first reference to a rotary I found was Felix Millet's 1888 motercycle the engine was in the wheel. The next was the 1894 Balzer moter car with a 5 cylinder. The langley Aerodrome was powered by a Balzer rotary that for some reason Manley converted to a radial. Cooling on Rotarys was very good so the low pressure air was not a big factor. I would much rather idle a rotary for a long period than a radial. VBR Brad