![Heinrich Zoelly mit Unterschrift](https://upload.wikimedia.org/wikipedia/commons/0/02/Heinrich_Zoelly_mit_Unterschrift.jpg)
Heinrich Zoelly (1862–1937) was a Mexican-Swiss engineer. He developed
steam turbine
A steam turbine is a machine that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft. Its modern manifestation was invented by Charles Parsons in 1884. Fabrication of a modern steam turbin ...
s and turbine-driven
locomotive
A locomotive or engine is a rail transport vehicle that provides the Power (physics), motive power for a train. If a locomotive is capable of carrying a payload, it is usually rather referred to as a multiple unit, Motor coach (rail), motor ...
s and patented the
geothermal heat pump
A ground source heat pump (also geothermal heat pump) is a heating/cooling system for buildings that uses a type of heat pump to transfer heat to or from the ground, taking advantage of the relative constancy of temperatures of the earth through ...
in 1912.
Life and work
Heinrich Zoelly was the fifth child of Franz Xaver Zoelly. His father, originally from Germany near
Klettgau
Klettgau (High Alemannic: ''Chleggau'') is a municipality in the district of Waldshut in Baden-Württemberg, Germany. It is the centre of the ''Klettgau'' historical region stretching across the Swiss border into the cantons of Aargau, Schaffhau ...
, had emigrated to
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
to seek better fortune. Heinrich was born in Mexico and received the Mexican citizenship. His father ran a hat factory in
Mexico City
Mexico City ( es, link=no, Ciudad de México, ; abbr.: CDMX; Nahuatl: ''Altepetl Mexico'') is the capital and largest city of Mexico, and the most populous city in North America. One of the world's alpha cities, it is located in the Valley o ...
with his brother John. When Henry was still a child, his father left Mexico because of political unrest and returned to Europe and settled in Switzerland. There, Henry attended primary school, skipping two grades before starting at the Federal Polytechnic Institute (which later became
ETH Zurich
(colloquially)
, former_name = eidgenössische polytechnische Schule
, image = ETHZ.JPG
, image_size =
, established =
, type = Public
, budget = CHF 1.896 billion (2021)
, rector = Günther Dissertori
, president = Joël Mesot
, ac ...
). He was just 20 years old when he earned his degree in mechanical engineering. After study trips to Mexico and Paris, Heinrich Zoelly went back to Switzerland in 1886. Two years later Zoelly applied in
Fluntern
Fluntern is a Quarter (urban subdivision), quarter in the district 7 (Zürich), district 7 in Zürich, Switzerland. It was formerly a municipality of its own, having been incorporated into Zürich in 1893. The quarter has a population of 7,325 di ...
for naturalization and became a Swiss citizen. Heinrich Zoelly was married and had five children.
In 1886 Zoelly entered the service of Zurich's Maschinenfabrik
Escher Wyss & Cie
Escher Wyss & Cie., also known as Escher Wyss AG, was a Swiss industrial company with a focus on engineering and turbine construction. Its headquarters were in the Zürich quarter of Escher Wyss, which takes its name from the company.
Histor ...
. He quickly became its technical director at the young age of 26. Thanks to him, the company flourished, which at this time manufactured various steam engines, water turbines, locomotives, traction engines and vessels.
His most significant development was the construction of a multi-stage steam turbine, initially used in water turbines. In 1903 Zoelly developed a multi-stage axial flow impulse turbine in collaboration with
Professor Stodola. Despite low vapor pressure (11 bar) and low temperature (185 °C), this achieved a considerable output of 370 kW and a thermodynamic efficiency of 62%. The original of the first machine of this type is now at the
Deutsches Museum
The Deutsches Museum (''German Museum'', officially (English: ''German Museum of Masterpieces of Science and Technology'')) in Munich, Germany, is the world's largest museum of science and technology, with about 28,000 exhibited objects from ...
. This turbine competed with other steam turbines developed about the same time in the world (Parsons, rake, plate, Curtis, Laval, and others) and was distributed worldwide through licensing.
In 1912 Zoelly was awarded an honorary degree from the
ETH Zurich
(colloquially)
, former_name = eidgenössische polytechnische Schule
, image = ETHZ.JPG
, image_size =
, established =
, type = Public
, budget = CHF 1.896 billion (2021)
, rector = Günther Dissertori
, president = Joël Mesot
, ac ...
, partly thanks to his work in turbine development.
Since Zoelly was convinced of the superiority of the steam turbine to the steam piston engine, in 1913 Escher Wyss & Cie. abandoned the production of steam engines and concentrated fully on turbines. Zoelly's vision also extended to steam locomotives (which traditionally used piston engines) using steam turbines as drive. Until his resignation from Escher-Wyss Zoelly devoted himself to the development of a steam turbine-driven locomotive, which he drove forward to serviceability (1926 Zoelly- SLM), and later in 1930
Krupp
The Krupp family (see pronunciation), a prominent 400-year-old German dynasty from Essen, is notable for its production of steel, artillery, ammunition and other armaments. The family business, known as Friedrich Krupp AG (Friedrich Krup ...
Zoelly
). Since diesel and electric power was increasing, the steam locomotive lost its significance.
Zoelly died in 1937 in his adopted hometown of
Zurich.
Further reading
* Schweizer Pioniere der Wirtschaft und Technik, Band 19: Drei Zürcher Pioniere: Paul Usteri (1853–1927) / Heinrich Zoelly (1862–1937) / Karl Bretscher (1885–1966), Zürich. Verein für wirtschaftshistorische Studien. 1968.
References
{{DEFAULTSORT:Zoelly, Heirich
1862 births
1937 deaths
Swiss engineers
ETH Zurich alumni
Mexican engineers
Mexican people of Swiss descent
Mexican emigrants to Switzerland