Gas Turbines

1912 M. Matricardi
1912 M. Matricardi, Italy
1912 M. Matricardi Italy

Early proposal of a free-piston gas turbine

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1925 Noack, Freudenreich
1925 Noack, Freudenreich, Switzerland
1925 Noack, Freudenreich, Switzerland   


Revolutionary proposal: The power take-off occurs on both the exhaust gases (2, 3) as well as electric (10, 4) with a linear alternator. The engine had a supercharger too (5). The proposal was never realized. 

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1932 Pescara, France
1932 Pescara, France
1932 Pescara, France

Earlier proposal of Pescara. This engine had outward compression, because the design was derived from the Pescara compressors

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1936 Pescara-Alsthom G18
1936 Pescara-Alsthom G18
1936 Pescara-Alsthom G18 (today Alstom)

From 1933, Robert Huber calculated several prototypes, which were tested extensively. The negotiations with the licensee Alsthom Belfort were very difficult. Of couse, success depended on whether the machines could provide the expected high efficiency.

1938 Pescara-Alsthom G30
1938 Pescara-Alsthom G30
1938 Pescara-Alsthom G30
1938 Pescara-Alsthom G30
1938 Pescara-Alsthom G30 (today Alstom)

The first plant with two engines and a turbo-generator was built in 1938. The test results were consistent with the calculated values.

1939 Pescara-Alsthom GS30
1939 Pescara-Alsthom GS30
1939 Pescara-Alsthom GS30 (today Alstom)

The experience with the two G30 engines have been integrated in the construction of the GS30. This engine had an output of 1000 HP. The outbreak of WW2 hampered the development of the work.

1941 Pescara, France
1941 Pescara, France
1941 Pescara, France

This patent shows the basis for the successful Pescara turbine drives. Outward compressing was replaced by inward compressing. This means that the scavenging air was compressed during inward stroke. This revolutionary design - combined with a mass-neutral piston synchronization - was a commercial breakthrough after WW2.

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1940-1950 Sulzer, Switzerland
1940-1950 Sulzer, Switzerland
1940-1950 Sulzer, Switzerland

The outward compressing Sulzer engine had twice the size of a GS30 but the same power output. The one and only sold equipment had to be withdrawn, however, because the promised power output could not be reached.

1943 Baldwin-Lima-Hamilton
1943 Baldwin-Lima-Hamilton
1943 Baldwin-Lima-Hamilton
1943 Baldwin-Lima-Hamilton
1943 Baldwin-Lima-Hamilton / Pratt & Whitney

On Navy order, 5 different outward compressing prototypes were built to drive a jet turbine.

A power to weight ratio of 2.5 kgs per hp was achieved. The development was abandoned in favor of conventional gas turbines.

The Pescara patent protection required an outward compressing and modifications in gas exchange.

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Pescara patent: 
Means for driving the propelling system for aircraft





1943 Baldwin-Lima-Hamilton / Pratt & Whitney
1943 Baldwin-Lima-Hamilton / Pratt & Whitney
1944-45 GS-34 Prototype
1944-45 GS-34 Prototype
1945 Pescara GS 34, SIGMA, Venissieux Lyon, France

The first 1250 HP prototype, built at SIGMA Lyon, on the test bench. The high expectations were met and soon a couple of engines were sold.

The Pescara Free Piston Gas Turbine
The Pescara Free Piston Gas Turbine
1948 SIGMA, Venissieux, Lyon, Frankreich
1948 SIGMA, Venissieux, Lyon, Frankreich
1948 SIGMA, Venissieux France

Pescara test bench

1950 Delivery of the first commercial GS34 engine
1950 Delivery of the first commercial GS34 engine
Legendary Pescara GS34
Legendary Pescara GS34
1951 Pescara small Marine Propulsion
1951 Pescara small Marine Propulsion
1951 Electricité de France
1951 Electricité de France: First commercial Pescara power plant (1400 kW)
1952 Regie Nationale Renault
1952 Regie Nationale Renault
1952 Regie Nationale Renault

First locomotive 040-GA-1 "La Pescara" with a free-piston gas turbine system Pescara. 1959-61 followed by two other Renault engines. In Russia, "Kharkov Locomotive Works," also bilt several locomotives with copied Pescara drives.

1953 Ajaccio, Corsica
1953 Ajaccio, Corsica: 2.8 MW Pescara power plant
1953 Cherbourg France
1953 Cherbourg France: 6 MW Pescara power plant
1954 CANTENAC, Augustin Normand
1954 CANTENAC, Augustin Normand, France
1954 CANTENAC, Augustin Normand, France

First cargo vessel having a free piston turbine power plant

Marine propulsion model
Marine propulsion model
Marine propulsion model
Marine propulsion model
1952-56: French Mine Sweepers
1952-56: French Mine Sweepers

1952 - 1956: French Navy ordered 20 minesweepers that were fitted with a Pescara Free Piston Turbine Propulsion: 

M701 Sirius (1952-1971), M702 Rigel (1953-1974), M703 Antares (1953-1981), M704 Algol (1953-1976), M705 Aldébaran (1953-1970), M706 Régulus (1952-1974), M707 Véga (1953-1981), M708 Castor (1953-1973), M709 Pollux (1953-1970), M740 Cassiopé (1953-1976), M741 Eridan renommé Aldébaran en 1977 (1953-1979), M742 Orion (1953-1970), M743 Sagittaire (1953-1979), M744 Achernar (1953-1970), M745 Procyon (1953-1970), M710 Pégase (1955-1974) M750 Bellatrix (1955-1974), M751 Denébola (1955-1974), M752 Centaure (1955-1970), M753 Fomalhaut (1955-1970).


Video about the French minesweeper
1954 Licensee Alan Muntz Co, England
1954 Licensee Alan Muntz Co, England
CS-75 420 hp engine, manufactured by Alan Muntz
CS-75 420 hp engine, manufactured by Alan Muntz
1955 Cooper-Bessemer Corporation
1955 Cooper-Bessemer Corporation
1956 Liberty Ship "William Patterson"
1956 Liberty Ship "William Patterson"
Pescara license engines manufactured at Cleveland Diesel
Three of the Pescara engines that were manufactured under license at General Motors / Cleveland Diesel
1956 Liberty Ship "William Patterson"

6000 KW propulsion, Pescara license

SAE Paper
Explanation of the free piston gasifier
1956 Liberty Ship "William Patterson"
1956 Liberty Ship "William Patterson"
1956 Liberty Ship "William Patterson"
1956 Liberty Ship "William Patterson", engine room
1956 Werkspoor N.V.
1956 Werkspoor N.V. Netherlands, Pescara licensing for marine engines
Werkspoor manufactured GS34
Werkspoor manufactured GS34 under Pescara license
1957 Ford Typhoon
1957 Ford Typhoon
1957 Ford Typhoon
1957 Ford Typhoon
Ford 160 HP Typhoon Engine
Ford Typhoon Engine: 160 HP, Ø 406 mm / 16", length 813 mm / 32"
1957 Ford Typhoon

Ford built a few prototypes, which were heavily inspired by the construction of Pescara. The first engine had 16 HP, this was followed by some 100 hp variants, and finally a version with 160 hp, which was fitted to a tractor.

The information to build the engine was offered to Ford by a security guard, who had photographed the Firebird XP 500 plans at General Motors at night.



Sept 1957: Popular Science, USA
Sept 1957: Popular Science, USA
1959 Agusta, Sicilia
1959 Agusta, Sicilia: 7,2 MW Pescara Power Plant
1959 + 1961 Regie Nationale Renault
1959 + 1961 Regie Nationale Renault
1959 + 1961 Regie Nationale Renault

Renault ordered two additional locomotives 060-GA-1 "Belphégor" having a 2400 hp Pescara Turbine Power Plant.

The FG9 - EMD's part in the free-piston adventure
The FG9 - EMD's part in the free-piston adventure
1959 
by Zsolt Kemény, NOHAB-GM Foundation, Hungary

1959 Motorenfabrik Darmstadt
1959 Motorenfabrik Darmstadt: Some engines have been built under license Pescara. Modifications of the original plans, however, led to problems.
1959 Doniambo, New Caledonia
1959 Doniambo, New Caledonia: 24 MW Pescara power plant
1959 Fritz Heckert
1959 Fritz Heckert with Demag Power Plant
1959 Fritz Heckert

Legendary Passenger Ship FRITZ HECKERT German Democratic Republic/Rostock, equipped with a Pescara-DEMAG free piston propulsion  

1959 ICI, England
1959 ICI, England: 12 MW Pescara power plant
1959 SIGMA
1959 SIGMA: 358 engines in service, total 316 MW
Licensee Smith's Dock Co. 1960 reports
Licensee Smith's Dock Co. 1960 reports
Licensee Smith's Dock Co. 1960 reports
Licensee Smith's Dock Co. 1960 reports
SIGMA Flyer
SIGMA Flyer

1967 End of SIGMA (Company flyer)

After 1962 retirement of the Pescara chief engineer Robert Huber, the decline of free-piston technology began. There were several reasons:

  • The slow-speed diesel engines meanwhile equalized the efficiency of free-piston gas turbines.

  • The Pescara GS34 engine - an improved prototype with a technical level of 1939 - was not developed further. The engine was a victim of its own success, a succeeding model was never developed.

  • Various successors (Stabine, Stelzer, Jarret, copycats) had conceptual or technical problems and damaged the reputation of the free-piston engines very much.
Stabine Generator
Stabine Generator
Stabine Generator
Stabine Generator

1969 Stabine SA, Le Creusot, Prototype

The pomised power output of some 15000 KW was never achieved. More than 150 Mio French Francs were invested, then the company went bancrupt.

This was a technical suicide for the free piston technology, that was developed by Robert Huber of "Bureau Technique Pescara" with 35 years of experience (1927 - 1962).

In relation to power, the moving mass of the Stabine engine was more than twice as heavy compared with the GS34. Accordingly, the piston acceleration was too low and thus the thermal efficiency was not achieved.

1996 TU Darmstadt, Karl Woerrlein
1996 TU Darmstadt, Karl Woerrlein
2001 Kvaerner ASA, Norway
2001 Kvaerner ASA, Norway
2001 Kvaerner ASA, Norway
2001 Kvaerner ASA, Norway
2001 Kvaerner ASA, Norway

Free-Piston Diesel Engine Timing and Control
Towards Electronic Cam- and Crankshaft


Dynamics and Control of a Free-Piston Diesel Engine

Tor A. Johansen, Olav Egeland, Erling Aa. Johannessen and Rolf Kvamsdal