German turbojet development

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T. A. Gardner
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German turbojet development

Post by T. A. Gardner » 08 Feb 2006 02:45

A start on German turbojet development. Feel free to add or correct the following: (Listed by RLM assigned number)

001 The original flight Henkel / Von Ohain turbojet engines. The RLM 001 designation was given to the HeS 8A engine of this series. The 8A was a progressive development of the HeS 8. That engine was developed from the previous HeS 6 and in turn from the HeS 3B engine. Development of this series of engines started pre-war and continued until September 1942 when the HeS 8A (RLM 001) was cancelled in favor of development of the 011 engine.
This series of engines had the following characteristics:
HeS 3B: 1100lbs thrust at 13,000 rpm. 725 lbs weight. Specific fuel consumption 1.6
HeS 6: 1300 lbs thrust at 13,000 rpm. 985 lbs weight.
HeS 8: 1100 lbs thrust at 13,000 rpm. 836 lbs weight, 30.5" diameter
HeS 8A: Thrust increased to 1300 lbs otherwise as for the HeS 8
The 001 used a single axial blower followed by a single stage centrifugal compressor. The combustion chamber was of conventional annular design. A single stage radial inflow turbine was used to run the engine.

002 Designed by Helmut Weinrich for Bramo / BMW. Contra-rotating turbojet proposal. Development slowed late 1939. All development ended 1942.

003 BMW design that replaced the 002 in development. First test run late 1940. Development continued until mid 1944 when a production model was reached. The definitive model was the 003A-2. 1760 lbs thrust at 9,500 rpm. 1250 lbs weight. Specific fuel consumption 1.47. 10 feet, 1" long x 27" dia.
Initially had a 6 stage compressor designed by W. Encke of AVA. Production model had 7 axial stages. The turbine was based on NACA blade profiles producing a 3.1 to 1 compression ratio. The combustion chamber was a conventional annular design and the turbine stage had one air-cooled axial turbine.. Development of the turbine was jointly done by Brown-Boveri, Mannheim and MAN. Running life was about 100 hours. A 003C version with an improved Brown-Boveri turbine was designed before the war ended but did not reach production.
The 003 required 500 manhours to assemble. Compare this to between 3000 and 5000 to produce a DB 600 series piston engine.

004 The production Junkers-Jumo engine. Development started in mid 1939. Anselm Franz of Junkers motor supercharger division was assigned as project manager. Franz rejected the Wagner-Müller engine (see below under 006) as too complex and advanced for rapid development. Franz instead opted for an engine that could be developed as rapidly as possible. The 004 was first test run in October 1940. Development of a production engine was complete in January 1942.
The 004 used an 8 stage axial compressor designed by W. Encke. The turbine was a single stage axial jointly designed with AEG steam turbine division. The compressor had a 3.1 to 1 compression ratio at 78% efficiency. A 6 can combustion chamber was utilized. The 004B, the production model, produced 1980 lbs thrust at 8,700 rpm. Weight was 1590 lbs. Dimensions were 12' 8" length, 31.5" diameter. Specific fuel consumption was 1.4. A progressive development, the 004C raised thrust to 2000 lbs.
The turbine blades were made from a folded manganese steel sheet metal with internal air cooling. The turbine and combustion chamber was anodized with aluminum. Service life was rated at 25 hours but 10 hours was closer to operational norms. The 004 used no nickel and only five pounds of chromium in its production. The 004 required about 700 manhours to construct.

006 The Wagner-Müller turbojet. Herbert Wagner joined Junkers Dessau in 1935. Prior to this Wagner had a long and extensive background in teaching and research at such institutions as the Technical University of Danzig, Technical University of Berlin and, with the DVL (Deutsche Versuchsanstalt für Luftfortforschung). Otto Mader, Junkers CEO set Wagner up at Junkers Engine in Magdeburg. Wagner brought in Max Müller, his assistant from the Technical University of Berlin to assist in design of a turbojet engine. Additional studies were carried out on development of a turboprop and diesel driven ducted fans.
By mid 1937 development had reached a stage where Wagner's design had taken shape. This engine had a 5 stage axial compressor with a 3 to 1 ratio, a single annular combustion chamber and a two stage axial turbine. The compressor was designed by Rudolph Freidrich. This design was unique using 50 percent reaction blading. The Engine was 24.3" in diameter.
Bench testing began in late 1938 but as late as mid 1939 Wagner was unable to get the engine to run under its own power. Most of these problems can be traced to very poor component matching. Wagner and Müller did not recognize the severity of this problem and were unaware of Von Ohain's work in this area of turbojet research.
Wagner and his team left Junkers in 1939 after a dispute with the management over development and joined Henkel to continue his engine development. With the war, Wagner had severe trouble recruiting and retaining engineers for his work and eventually left Henkel in frustration in May 1942.
The RLM assigned the designation 006 to the Wagner-Müller engine. By the end of 1942 this engine had progressed to a point of developing 1900 lbs thrust. The engine weighed only 857 lbs. With Henkel concurrently developing Von Ohain's 011 engine and a number of RLM engineers having objections to the use of reaction turbine blades as inefficient the RLM persuaded Henkel to drop the 006 from development in late 1942. As an after note, the 006 really had alot of development potential but, like many other choices the RLM made, it was cancelled right on the brink of useful development in favor of a future "better" design, the 011.

007 The 007 was a Daimler-Benz development. Daimler-Benz was a late comer to turbojet development. DB rejected any work on a turbojet engine prewar. DB hired Karl Leist from DVL's supercharger division to develop a jet engine for DB.
The design Leist came up with was a very complex contra-rotating turbofan engine. Throughout development DB continued to show minimal interest in this engine. Work on the 007 continued through late 1943 when the RLM cancelled the project due to lack of progress.

011 This was the last wartime engine developed by Henkel and Von Ohain. Development on the 011 started in September 1942. The 011 was a very ambitious and much larger design than previous engines Von Ohain had developed. The 011 was 13 feet long, 42.4" in diameter and weighed 2090 lbs. It developed 2860 lbs thrust at 11,000 rpm and a specific fuel consumption of 1.31.
The design followed the pattern of the 001. The compressor section consisted of 1 axial / centrifugal stage followed by 3 axial stages. A straight annular combustion chamber was utilized. The turbine section had 2 axial turbines.
A turboprop version, the 021, was to be developed by Daimler-Benz. Testing of the 011 was underway when the war ended.

012 The Junkers Jumo competitor to Henkel's 011. This engine only reached preliminary design stages when the war ended. It was envisioned as a very large engine producing 6600 lbs thrust and weighing about 4400 lbs. The turboprop version was designated the 022

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Re: German turbojet development

Post by Cantankerous » 15 Mar 2021 02:07

The BMW company proposed a next-generation turbojet, the BMW 018, which could produce 7,700 pounds of thrust. A turboprop-powered version of the BMW 018 was planned as the BMW 028, which was to have a power output of 6,200 shp. The proposed Junkers EF 132 strategic jet bomber would have been powered by either the Jumo 012 or BMW 018.

As a side note, when the Soviets took custody of the Junkers factory in Dessau after World War II, they took possession of the engineering drawings for the Jumo 022 turboprop, and Kuznetsov was entrusted to reverse-engineer the Jumo 022 to create the TV-2 turboprop, which went into production as the NK-4 and later spawned the NK-12 turboprop that powered the Tu-95 strategic bomber, Tu-114 airliner, and An-22 heavy-lift transport.

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