Two kinds of Steam Turbine. Most models will be "impulse" turbines due to the difficulties of producing the complex curves for a reaction turbine. Most commercial turbines are reaction. With an impulse turbine, steam velocity is everything, but there are tradeoffs. Steam is heated & can expand. In that case, providing more volume just before injection to the rotor blades converts as much heat as possible to velocity. So, a diverging nozzle (such as the "trumpet" nozzle) works better.
The N&W's Jawn Henry: The Norfolk & Western's experimental Jawn Henry was the last in a short series of steam turbine locomotives tested by three different railroads between the 1930s and 1950s including the Pennsylvania and Chesapeake & Ohio.
(Posted from 5axismachiningchina.com) Check out these turbine blade machining images: Image from page 271 of “Steam turbines; a practical and theoretical treatise for engineers and students, including a discussion of the gas turbine” (1917) Image by Internet Archive Book Images Identifier: steamturbinespra00moye Title:... Read more on http://www.5axismachiningchina.com/image-from-page-271-of-steam-turbines-a-practical-and-theoretical-treatise-for-engineers-