PROGRESS IN TURBINE SHIP PROPULSION. 

 By Francis Hodgkinson, Esq., Visitor. 



[Read at the twenty-sixth general meeting of the Society of Naval Architects and Marine Engineers, held in 



Philadelphia, November 14 and IS, 1918.] 



The extraordinary development of the steam turbine for land purposes, almost 

 entirely supplanting the reciprocating engine, rendered the application of steam tur- 

 bines for the propulsion of ships a natural sequence. 



Sir Charles A. Parsons commenced the development of the reaction steam tur- 

 bine in 1884. This was the first reduction of turbines to practice, although Dr. 

 De Laval developed his small high-speed geared machine about the same time, and 

 there had been some sporadic attempts at development prior to this. 



Five years thereafter Sir Charles commenced their application to the small- 

 sized central power stations then being built, he realizing the advantages of the 

 steam turbine when built for large capacities as compared with the small lighting 

 sets built previously. 



During 1884 turbines as large as 500 kilowatts had been built for central sta- 

 tions in London, and at that time attention was given to the application of tur- 

 bines to marine propulsion and plans were made for the building of the historic 

 Turbinia. The progress up to that time was indeed rapid, when the limited appli- 

 cation of high-speed machinery is considered. On the other hand, it is unfair to 

 compare what has been accomplished in the thirty years of development of the steam 

 turbine with the ninety years required for the reciprocating engine. In the case of 

 the latter the mechanical arts had to be developed along with it, all of which were 

 available iot the turbine engineer. 



The Turbinia was built especially to demonstrate the possibility of turbine propul- 

 sion and was of torpedo-boat type, 100 feet long, 9 feet beam, 3 feet draught, 44 

 tons displacement, and was completed in 1895. 



The first machinery comprised a single complete expansion turbine of radial 

 flow type direct connected to the propeller. The turbine was intended to develop 

 2,000 horse-power' at 2,000 to 3,000 revolutions per minute. There were but little 

 data available at that time concerning propellers to operate at such speeds, and sev- 

 eral propellers were tried with no particular success. The trials of these several 

 propellers would be of much interest if their records were available. They led to 

 extensive experiments on the part of Sir Charles regarding cavitation. 



It was not until in 1896 that anything like success was attained when the Tur- 

 binia's machinery was changed over to three compounded turbines, the steam pass- 

 ing them in series, each driving one of the three propeller shafts, and each shaft 



