Junkers Jumo 012
The Junkers Jumo 012 was a jet engine from Junkers Flugzeug- und Motorenwerke AG , which was designed in Germany during the Second World War and later further developed in the Soviet Union . A flight operation did not take place. The Jumo 022 , Kuznetsov NK-4 , Kuznetsov NK-12 , Pirna 014 and Pirna 018 were later developed on the basis of this type of engine .
Development history
The development of the Jumo 012 began in 1943 when the Technical Office, which is part of the Reich Aviation Ministry (RLM), asked Junkers for more powerful engines. The Jumo 004B drive with a thrust of 9 kN, which was ready for series production at the time, was not and should not be sufficient for the newly planned aircraft such as Junkers Ju 287 (2 × Jumo 012 or 2 × BMW 018 ) or Heinkel He 343 (2 × Jumo 012) can be supplemented by a three times more powerful engine with around 30 kN. RLM internally the project was run under the number 109-012, which explains the name (JUnkers MOtor + project number).
The development work was stopped in December 1944 at the Junkers headquarters in Dessau and relocated to Brandis , Aken and Mosigkau . The reasons for this are not known. For the ten test engines that had already been ordered, only a few parts - including rotor components - had been manufactured by the end of the war, but they could no longer be tested. American troops marched into Dessau on April 23, 1945 and subsequently confiscated numerous documents and components from Junkers, including those from Jumo 012.
On July 5, 1945, Soviet troops took over Dessau. While other branches of industry were being dismantled as part of the reparations payments, the Soviet Union wanted to use the knowledge of the engine specialists and prevent their further migration to the other occupation zones. Towards the end of 1945, the OKB-1 special design office was set up in Dessau . Although many documents, test engines and systems had been transported to the USA or the Soviet Union or destroyed and skilled workers had fled, development work on the Jumo 012 as well as on the Jumo 004C and Jumo 022 was resumed under Soviet supervision. In this way, the backlog of the Soviet Union in this area was to be remedied and powerful drives were to be made available for their own projects under tight deadlines. The first run of the Jumo 012 took place on June 24, 1946. A total of three test engines were built, one of which was destroyed by an accident and the other two initially could not safely achieve the required performance.
On October 22, 1946, a selected group of specialists and their families were brought from Dessau to Uprawlentscheski Gorodok , a district of Kuibyshev (today Samara) as part of the Ossawakim campaign . The test facilities and offices were dismantled and transported there by the end of 1946. In Kuibyshev, the specialists worked in the specially established State Experimental Plant No. 2, from which OKB 276 emerged in August 1953 and today's Russian manufacturer Kuznetsov in 2009 .
The engine was fundamentally revised in Kuibyshev under the new head of development Ferdinand Brandner . For this version, then called Jumo 012B, production of five prototypes began at the end of 1947. The tests began in June 1948. Success was achieved, although at the end of the year a 100-hour approval test had to be aborted after 94 hours as a result of a broken blade.
The engine type was not used in flight. Independently of its development, the Soviet Union procured the British Nene engine from the manufacturer Rolls-Royce and developed it first into the Klimow RD-45 and later the Klimow WK-1 . The RD-45 was more compact and lighter by a factor of 1.5 with comparable thrust. That was the decisive factor in ending the development of the Jumo 012 at the end of 1948.
Technical specifications
Conceptually, the engine was basically a three times enlarged Jumo 004B with a length of 4.86 m and a diameter of 1.06 m. As it was designed as a turbojet , it was equipped with an eleven-stage axial compressor that had been designed in terms of flow technology at the aerodynamic research institute in Göttingen . The combustion chamber was divided into eight individual combustion chambers . The turbine was divided into two stages and had air-cooled blades. The thrust nozzle was variably adjustable.
With the variant 012B, the engine was fundamentally revised in 1948. The weight was drastically reduced from around 2000 kg to only 1350 kg and the compressor now had twelve stages. The combustion chamber was designed as a combination of a single and ring combustion chamber with twelve burners, which promised a better degree of burnout. The nozzle was no longer adjustable. The thrust was increased to 3000 kp (29.4 kN).
Several engine types were derived from the Jumo 012, all of which were developed by the same group of engineers and therefore build on one another in terms of design. The following table gives an overview of these engines and their technical data.
| Data | Jumo 012 | Jumo 022 | Kuznetsov NK-12 | Pirna 014 | Pirna 018 |
|---|---|---|---|---|---|
| Type | Turbojet | Turboprop | Turboprop | Turbojet | Turboprop |
| Start thrust | 2780 kp (27.3 kN) | - | - | 3150 kp (30.9 kN) | - |
| equivalent shaft power (starting power) | - | 4412 äkW (6000 äPS) |
8820 äkW (12000 äPS) |
- | 3680 äkW (5000 äPS) with 670 kp (6.57 kN) residual thrust |
| Air flow | ~ 50 kg / s | 50 kg / s | 62 kg / s | 52 kg / s | 31.3 kg / s |
| Weight | ~ 2000 kg | 2600 kg (with propeller) |
2300 kg (without propeller) |
1060 kg | 1300 kg (without propeller) |
| overall length | 4.86 m (without nozzle) |
5.64 m (with propeller) |
6.0 m | 3.31 m | 3.68 m |
| propeller | - | 2 counter-rotating coaxial three-bladed adjustable propellers | 2 counter-rotating coaxial four-blade adjustable propellers | - | Four-blade variable pitch propeller AW-68A |
| compressor | 11 levels | 11 levels | 14 steps | 12 levels | 13 levels |
| turbine | 2 steps | 3 steps | 5 levels | 2 steps | 4 levels |
| plane | - | - | Tupolev Tu-95 and others | 152 with 4 × Pirna 014 |
153 with 2 × Pirna 018 154 with 4 × Pirna 018 |
| annotation | Data refer to variant Jumo 012A |
Data refer to variant NK-12 |
Data refer to variant Pirna 014 A-0 |
Data refer to the latest development status |
Derivatives
Jumo 022
Parallel to the work on various jet engines, the RLM also called for the development of propeller turbine engines (PTL engine, turbo-prop for short), which promised lower fuel consumption compared to jet engines for a typical mission profile of aircraft with a long range and high cruising speed. The Jumo 022 project, a turboprop version of the Jumo 012, was started at Junkers in 1943. With a projected equivalent shaft power of 4418 ekW (6000 ePS), it ranks between the smaller 109-021 from Daimler and the larger BMW 109-028 .
The Jumo 022 is initially based on a Jumo 012A, which has been expanded by a turbine stage and equipped with two coaxially opposing three-blade adjustable propellers and a corresponding gear. The propeller diameter was 3.5 m, the total length 5.64 m. Later there were other changes compared to the Jumo 012 in order to increase the efficiency, such as a reduction of the gap dimensions in the compressor or an improved inlet. The number of compressor stages rose to 14. The output was reduced to 3677 äkW (5000 äPS) in the TW-022 version and 4192 äkW (5700 äPS) in the TW-2 version with a simultaneous reduction in specific fuel consumption.
The development work was stopped in 1944, so the design was not finished by the end of the war. The transmission in particular caused problems. However, work should be resumed by OKB-1 after the war, as the Soviet Union saw a corresponding need. At the end of 1947, at the State Experimental Plant No. 2 in Uprawlentscheski Gorodok, the theoretical work was finished and the production of three prototypes began and test stands were set up. The work on the turboprop engines was then concentrated on the Jumo 022 - then referred to as TW-022 - under the new head of Kuznetsov , and the BMW 028 abandoned. The acceptance tests were successfully completed in 1950 and a shaft output of more than 5700 äPS was demonstrated in the 100-hour approval test. The engine, then called the TW-2 (also NK-2 according to other sources), was tested in flight on a Tupolev Tu-4 from 1951 .
Later the versions TW-2M with 5626 äkW (7650 äPS) and TW-2F with 4596 äkW (6250 äPS) were developed.
After its approval, the TW-2 was further developed by a Soviet company into the serial version TW-4 or Kuznetsov NK-4 and then used in the aircraft Antonov An-8 and An-10 as well as the Ilyushin Il-18 . However, after incidents it was quickly replaced by other engines.
Kuznetsov NK-12
After the approval of the TW-2, the work in the State Experimental Plant No. 2 concentrated on the development of a 10,000 hp, later 12,000 hp turboprop engine, which was also successfully completed in 1953. The 2TW-2F variant, which has meanwhile been tried and tested, in which two TW-2Fs act on the gearbox and the propeller, turned out to be unsuitable. The drive, designated as the Kuznetsov NK-12 in the later production version , was tested and used in the Soviet Tupolev Tu-95 bomber from 1954 . In 1955 the Tupolev Tu-114 was also equipped with this engine. As with the TW-2, the NK-12 was started by a small gas turbine developed by the German specialists. Later variants of the NK-12 developed up to 15,000 hp and were used in the Antonov An-22 , Tupolev Tu-142 and Tu-126 and the Ekranoplan A-90 Orljonok .
Pirna 014
After the German specialists returned to the GDR, the Pirna 014 was developed there at VEB Entwicklungsbau Pirna , which was supposed to drive the 152 passenger jet . It is constructively viewed as a successor to the Jumo 012. Until the program was discontinued in 1961, several versions were developed and a pilot series was produced. A flight test took place.
Pirna 018
The Pirna 018 was a single-shaft turboprop engine that was initially intended to power the twin-engine 153 and four-engine 154 at the end of 1955 . Experience from the successful NK-12 was incorporated into the development. After several revisions in the project, development was canceled in 1959. A total of three test engines were produced, only two of which ran on the test benches. A flight test did not take place.
swell
- Klaus-Hermann Mewes: Pirna 014 . Aero engines of the GDR. 1st edition. AVIATIC Verlag, Oberhaching 1997, ISBN 3-925505-39-3 , p. 159 .
- Antony Kay: German Jet Engine and Gas Turbine Development 1930–1945 . Airlife Publishing Ltd, Shrewsbury 2002, ISBN 1-84037-294-X (English).
Individual evidence
- ↑ a b c d e Reinhard Müller: Brunolf Baade and the aviation industry of the GDR: the true story of the jet airliner 152 . Sutton, 2013, ISBN 978-3-95400-192-7 ( limited preview in Google Book Search [accessed September 1, 2018]).
- ^ A b c d e f Antony Kay: German Jet Engine and Gas Turbine Development 1930–1945 . Airlife Publishing Ltd, Shrewsbury 2002, ISBN 1-84037-294-X (English).
- ^ Rainer Appelt: A quick end to the GDR aviation industry . In: Aviation Classics . No. 3 , 2014, ISSN 1860-0654 ( klassiker-der-luftfahrt.de [accessed February 20, 2018]).
- ↑ a b c d e f g h i Klaus-Hermann Mewes: Pirna 014 . Aero engines of the GDR. 1st edition. AVIATIC Verlag, Oberhaching 1997, ISBN 3-925505-39-3 (159 pages).
- ↑ a b c Holger Lorenz: The turbine aircraft Dresden-153A from 1959 . Erzdruck GmbH, Marienberg 2015, ISBN 978-3-9816919-6-2 , p. 120 .
- ^ Rainer Appelt: German specialists in the USSR from 1946–1956 - kidnapping or immaterial reparation? In: www.freundeskreis-luftwaffe.de. Retrieved October 21, 2018 (presentation by Konrad Eulitz).
- ↑ Mario Beck: Exciting journey through time into aviation history . In: Leipziger Volkszeitung . February 16, 2016 ( pressreader.com [accessed October 21, 2018]).
- ^ The Historical Chronicles of Kuznetsov (JSC). (No longer available online.) In: kuznetsov-motors.ru. Archived from the original on September 16, 2017 ; accessed on March 4, 2018 (English, story of the Russian engine manufacturer Kuznetsov). Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ a b c d Dmitrii Alekseevich Sobolev, Dmitrii Borisovic Chazanov: The German imprint on the history of Russian aviation . Rusavia, Moscow 2001, ISBN 5-900078-08-6 (English, airpages.ru [accessed on August 26, 2018] Internet site based on the work mentioned).
- ↑ Ferdinand Brandner : The propeller turbine development in the Soviet Union . In: Schweizerische Bauzeitung . tape 75 , no. 33 , 1957, pp. 520-524 , doi : 10.5169 / seals-63405 .
- ↑ Ulrich Unger: German start for a Soviet engine era: PTL engine Kuznetsov TW-2 . In: Fliegerrevue Edition . No. 06 . FlugVerlag Berolina, Berlin 1996.
