Monotube steam generator
{{Short description|Water boiler}}
File:Peruvian torpedo boats.jpg
A monotube steam generator is a type of steam generator consisting of a single tube, usually in a multi-layer spiral, that forms a once-through steam generator (OTSG). The first of these was the Herreshoff steam generator of 1873.{{cite journal
|journal=Light Steam Power
|date=July–September 1975
|volume=XXIV
|issue=3
|pages=157–159
}}
Principles
For the sake of efficiency, it is desirable to minimise the steam content of the generator. Heat can then be transferred efficiently into liquid water, rather than into low-density steam. Monotube steam generators may either boil gradually along their length, usually pumped circulation systems,{{cite web|author=Newest on Process Equipments |url=http://www.enggcyclopedia.com/2012/01/boilers-circulation-systems-natural-circulation-forced-circulation/ |title=Boilers circulation systems: natural circulation and forced circulation |publisher=Enggcyclopedia |date=2012-11-25 |accessdate=2012-12-02}} but where this boiling does not disrupt the circulation. Otherwise they can use the Benson supercritical system, where the pressure is sufficient to prevent boiling (within the heated volume) altogether.{{cite web |url=http://www.babcock.com/library/pdf/br-1658.pdf |title=Archived copy |accessdate=2008-10-08 |url-status=dead |archiveurl=https://web.archive.org/web/20100923184555/http://babcock.com/library/pdf/BR-1658.pdf |archivedate=2010-09-23 }}
Examples
File:White steam car steam generator (Rankin Kennedy, Modern Engines, Vol III).jpg
Examples of Monotube steam generators include:
- Industrial steam generators {{Cite web |url=http://www.claytonindustries.co.uk/Steam%20Generators/Principals%20of%20Operation.htm |title=Clayton Thermal Products UK - Steam Generators Principle of Operation |access-date=2012-12-09 |archive-url=https://web.archive.org/web/20120209180630/http://www.claytonindustries.co.uk/Steam%20Generators/Principals%20of%20Operation.htm |archive-date=2012-02-09 |url-status=dead }}
- The water-tube boilers of the monotube type used in steam cars, such as:
- AMC
- Clayton Steam Generator
- Doble steam car
- Gardner-Serpollet
- Locomobile Company of America
- White Motor Company, US patent 659,837 of 1900 {{Cite web |url=http://whitesteamcar.com/White_Steam_Car_Registry/Patents_files/Steam%20Generator%20%28US%20Pat%20659837%29.pdf |title=Archived copy |access-date=2012-12-09 |archive-date=2013-11-11 |archive-url=https://web.archive.org/web/20131111180559/http://whitesteamcar.com/White_Steam_Car_Registry/Patents_files/Steam%20Generator%20%28US%20Pat%20659837%29.pdf |url-status=dead }}
Flash boilers
{{main|Flash boiler}}
A flash boiler is a particular type of low-water-content monotube boiler. Modern use is confined to model steam boats but, historically, flash boilers were used in Gardner-Serpollet steam cars.