Heinrich Zoelly (1862–1937) was a Mexican-Swiss engineer. He developed

steam turbine A steam turbine or steam turbine engine is a machine or heat engine that extracts thermal energy from pressurized steam and uses it to do mechanical work utilising a rotating output shaft. Its modern manifestation was invented by Sir Charles Par ...

s and turbine-driven

locomotive A locomotive is a rail transport, rail vehicle that provides the motive power for a train. Traditionally, locomotives pulled trains from the front. However, Push–pull train, push–pull operation has become common, and in the pursuit for ...

s and patented the

geothermal heat pump A ground source heat pump (also geothermal heat pump) is a heating/cooling system for buildings that use 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, had emigrated to

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

to seek better fortune. Heinrich was born in Mexico and received Mexican citizenship. His father ran a hat factory in

Mexico City Mexico City is the capital city, capital and List of cities in Mexico, largest city of Mexico, as well as the List of North American cities by population, most populous city in North America. It is one of the most important cultural and finan ...

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 ETH Zurich (; ) is a public university in Zurich, Switzerland. Founded in 1854 with the stated mission to educate engineers and scientists, the university focuses primarily on science, technology, engineering, and mathematics. ETH Zurich ran ...

). 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 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. 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 museum, science and technology museum, technology, with a ...

. 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

, 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 Friedrich Krupp AG Hoesch-Krupp (formerly Fried. Krupp AG and Friedrich Krupp GmbH), trade name, trading as Krupp, was the largest company in Europe at the beginning of the 20th century as well as Germany's premier weapons manufacturer dur ...

Zoelly). Since diesel and electric power was increasing, the steam locomotive lost its significance. Zoelly died in 1937 in his adopted hometown of

Zurich Zurich (; ) is the list of cities in Switzerland, largest city in Switzerland and the capital of the canton of Zurich. It is in north-central Switzerland, at the northwestern tip of Lake Zurich. , the municipality had 448,664 inhabitants. The ...

References

{{DEFAULTSORT:Zoelly, Heirich 1862 births 1937 deaths Swiss engineers ETH Zurich alumni Mexican engineers Mexican people of Swiss descent Mexican emigrants to Switzerland

Life and work

Further reading

References