Professor Auguste Camille Edmond Rateau (1863-1930) of the Société Rateau, which employed 3,000 persons
A half size model of a six-stage Rateau steam tubine is on display at the Musée des Arts et Métiers. The model was made by J. Boudin in 1912. The full-size turbine was made for the Société minière du Haut-Katanga. See photo.
1930 Obituary 
Professor AUGUSTE RATEAU was born at Royan in 1863.
He commenced his training in 1881 at the Ecole Polytechnique and left at the head of the list in 1883; he continued his studies at the Ecole Superieure des Mines from 1883 to 1886, was Engineer in the State Mining Corps at Rodez in 1887-8, and was appointed Professor of the Industrial Electrical Course at the Ecole Superieure des Mines de Paris 1902 to 1910. During the later years of this appointment he wrote a number of technical papers relating to the flow of fluids and the problems involved in the application of theory to practice in steam and hydraulic turbine construction, as well as in that of centrifugal fans.
In 1900 he wrote a treatise on turbo-machinery which was, and still remains, the engineer's handbook on this subject. His Papers on the Theory of Propellers (1900), Anemometers and Pitot Tubes (1898), Electro-Condensers (1900), the Flow of Steam through Orifices (1902), Hydraulic Brakes and the Measurement of the Mechanical Equivalent of Heat (1913) and his masterly lecture on Aerodynamics delivered before the French Institution of Civil Engineers in 1912, showed the breadth and thoroughness of his scientific and industrial knowledge. The major portion of his work led to great industrial changes; the laws of similarity and his charts for turbine performance are in use by all French turbine constructors.
Among the results of his work are the multicellular turbine, a type apart, and it is thanks to Rateau that utilization of the exhaust has come into general use. The results obtained by the supercharging of internal-combustion engines led Rateau to the extension of this method to Diesel engines, and quite recently he had the great satisfaction of obtaining improved results by the application of supercharging to marine oil-engines. Within the last few days of his life he wrote an article for the Revue Generale des Sciences in which he dealt with the extension of the application of this method in practice.
Professor Rateau was elected a Member of the Institution in 1904 and was awarded the Hawksley Medal in 1922 for his Paper on Turbo-compressors for Aeroplanes, read at the Summer Meeting in Paris. He was an Honorary Member of the American Society of Engineers, Doctor of Laws of the University of Wisconsin, Doctor of Engineering of the Technical University of Charlottenburg (1906), Doctor of Laws of the University of Birmingham, Doctor of the University of Louvain, Commander of the Legion of Honour, Member of Council of the Societe d'Encouragement pour l'Industrie Nationale, President of a Section of the Council of the French Institution of Civil Engineers and President of the French Aeronautical Society; in addition to these he was member of several French Ministerial Committees — President of the one dealing with normalization, and Vice-President of the Committee on Commerce and Industry.
During the War, on the special appeal from the Government for munitions, Professor Rateau built and equipped a model shell factory which turned out more than four million shells. His application of the turbo-compressor to aircraft for enabling the torque of the engine to be maintained at any altitude was of the greatest value to aviation, civil and military. Nor was this all, for some of the most important secrets were entrusted to him for development, and in particular that relating to the recoil brakes for field guns.
He died on the 13th January 1930.
"THE LATE PROFESSOR AUGUSTE RATEAU.
A very prominent figure is lost to the engineering world by the death of Professor Auguste Bateau, which occurred in Paris on the 13th inst. Born at Royan in October, 1863, the subject of our memoir,; after taking the usual course at the Cognacq grammar school, pursued his studies at the Ecole Polytechnique and at the Ecole Superieure des Mines, Paris. Whilst still a student at the former, and but 21 years old, he read before the Blois meeting of the French Association for the Advancement of Science, a paper in which he discussed the accelerations of a plane figure moving in a plane, and in 1887, and whilst still a student at the School of Mines, he presented to the Academie des Sciences a note on the theory of the Belleville spring, whilst a year later he published an important etude on the Piccard method of evaporating liquids by means of a heat pump, a process which, in principle has attracted further attention of late years. In 1888, Rateau was appointed Professor at the Saint-Etienne School of Mines, and in 1902, he' became Professor of 'Electrical Engineering at the Ecole Superieure des Mines de Paris, but resigned the chair till 1910, owing to the' 'success of his industrial enterprises.
Rateau had early begun to realise the promise and possibilities of turbo-machinery of 'all types, and in 1890, he published, his Etudes surles Turbines A Vapeur, in which it may be noted that he realised the' advantages of the double rotation type, but, like others, was deterred from pursuing the matter further by the very serious mechanical difficulties involved. The problem was, in fact, not solved, till Ljungstrom produced his turbine some twenty years later. As the result of careful tests of mining fans, and of a thorough study of the theory, Rateau was led to the inventtion of a greatly improved type, and the knowledge and experience thus gained proved invaluable later on when developing his turbo-compressor.
It is predominantly to Professor Rateau that must be attributed the introduction of the compound impulse steam turbine. The idea was not new, and in essentials had been patented many years before, but there is at times a vast gulf between paper projects and commercially successful machines, and this has been pre-eminently the case with the steam turbines of every variety. Rateau exhibited at the Paris Exhibition of 1900, complete designs for a multi-stage impulse turbine, which he suggested for use on a torpedo boat, but the idea was not then taken up. He made many experiments about this time on the discharge of steam from nozzles, and on the efficiency of buckets, publishing important papers, which, at that date, were of very greater service to every student of the subject in question. Naturally enough now these observations are out of date, as almost invariably happens with the work of every pioneer in science or technology. With the growing prosperity of the companies formed to work his inventions, Rateau had less time for scientific research.! One of the earliest of the Rateau turbines, rated at 300 h.p., was erected at the Brouay works in 1902 and is still at work. This turbine used low-pressure steam and was, perhaps, responsible for directing Rateau’s attention to the advantages, in ' certain cases, of exhaust steam turbines, and incidentally led to the invention of his steam accumulators and its accessories. These have proved invaluable in steel works and in other undertakings where there is a large but intermittent supply of exhaust steam. The technical difficulties involved in designing the turbine so as to secure satisfactory running under such widely varying conditions were ingeniously and successfully surmounted.
Another direction in which Rateau led the way, was in the design of compound centrifugal compressors of excellent efficiency and of very high output. In the course of his experimental work, he made use of an impeller with a tip speed of 870 ft. per second, and attained a pressure of 8.25 lb. per square inch.
Still later, with an impeller, machined out of the solid, a peripheral speed of 1,640 ft. per second was reached and a compression ratio of more than 3. During the war, Rateau organised a shell factory which turned out over four million shells. It was at this time that he devised his turbine super-charger for aero-engines which made it possible to maintain the engine-power at high altitudes. His original supercharger was turbine-driven, the turbine being actuated by the engine exhaust, but, later on, working in conjunction with Messrs. Farman, he devised a gear driven super-charger, which had the advantage that it could be disconnected at will. In recent developments, gas-driven Rateau superchargers have been fitted to the Diesel engines of the Agamemnon and Menestheus of the Holt line of steamers. An efficiency of 72 per cent, is claimed for the turbine and compressor and one of 60 per cent, overall.
Owing to his mechanical insight and excellent business abilities, Professor Rateau’s industrial enterprises have proved highly prosperous. The first Soeiete Rateau was founded in 1903, and this has now developed into an undertaking employing over 3,000 hands, with many foreign branches.
Professor Rateau contributed two papers to the proceedings of British technical societies,. The first of these read before the Institute of Mining Engineers at Newcastle in 1902, dealt with “The Utilisation of Exhaust Steam by Steam Accumulators and Condensing Turbines,” whilst at a meeting of the Institution of Mechanical Engineers in 1922, he read a paper on “ The Use of the Turbo-Compressor for Attaining the Greatest Speeds in Aviation.” He also gave a lecture oh the occasion of his receiving the James Watt medal.
Amongst his distinctions, it may be noted that he was awarded a doctor’s degree by the Universities of Birmingham, of Wisconsin, of Charlottenburg and of Louvain. He was the second engineer to receive the high distinction of election to the Institut (AcadAmie des Sciences). He also held the rank of commander in the Legion d’honneur."
- The Late Professor Auguste Rateau
"To the Editor of Engineering.
Sir, — In,your issue of January 17, page 86 ante, you published a very exhaustive account of the life work of our late regretted Chairman, Professor A. Rateau.
May we point out a small inaccuracy which occurred in one of the last paragraphs of your article, dealing with the gas-driven Rateau superchargers installed on hoard the Agamemnon and Menestheus? You state that the efficiency for the turbine and compressor was 72 per cent., corresponding to a 60 per cent, overall efficiency. The latter figure is accurate, hut the first, giving the average efficiency of the turbine and compressor considered separately should read 77 per cent., the overall efficiency of the set being the product of the efficiency of the turbine and compressor. In fact, Professor Rateau estimated that the efficiency of the compressor was somewhat above the average of 77%, ahd that of the turbine accordingly somewhat below.
As the research work of Professor Rateau, in connection with superchargers for Diesel engines, was specially directed towards obtaining high efficiencies, and as he felt very gratified with the results actually obtained, we take the liberty of pointing out this slight error.
For and on behalf of Société Rateau,
F. Rieder, Branch Manager.
28, Russell-square, London, W.C.l. February 1, 1930,