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My mistake. In German it means "injection."PS: "Einspritzung" simply means "injection" in German, not "sequential fuel injection" or "port injection" or any other limited meaning you wish to assign to it.
Einspritzung.
The entire fuel is injected with a sequential injection so promptly before the end of the sucking in act that it arrives without pre-ageing with air flowing in into the cylinder.
This kind of injection can be combined only with multipoint injection.
Einspritzung-Pump nozzle injection is shortened frequently with PD or PDE. Bosch uses the abbreviation UIS for unit Injector system.
With the pump nozzle injection are fuel-inject pump and nozzle for each cylinder in only one construction unit in summary. That means: High pressure ( approx. 2050 bar ( of S.A.. Table )) at the injecting element of each cylinder one produces separately.
The paragraph you refer to (on page 1 of the document) appears to be discussing the use of twin pressure relief valves for the two-speed supercharger in the BMW 801 which sacrificed some 80hp and caused reliability issues, discovered as a result of testing in 1942.
I've looked up every link you've posted and am still yet to see this fabled "special C3-injection system" which "injects fuel into the left air intake to provide additional cooling and prevent predetonation" in any of them.
I still think the claims made in the thread, the essence of your assertion is a complete misinterpretation, because it doesn't make engineering sense. Everything in my experience has made engineering sense or has been incorrect.Gille said:If you're using machine translation then you must have typed pretty quick to get that whole article in in only half an hour and translated, you did claim that you had read it.
The paragraph you refer to (on page 1 of the document) appears to be discussing the use of twin pressure relief valves for the two-speed supercharger in the BMW 801 which sacrificed some 80hp and caused reliability issues, discovered as a result of testing in 1942.
Close but not really, which just goes to show the limitations of electronic translation programs.
What that para (under the heading Doppel oder Einzeldusen) is talking about is a trial replacing the double exhaust pipes with a single pipe, producing an 80PS boost. On 16 March 1943 Rechlin advise Focke Wulf that the tests on this modification are succcessful and that it should be implemented however Focke Wulf decide not to changeover but instead apply the change to the 801E engine.
I'm not a native speaker but here's my best effort at summaring the rest of the article:
The para headed Versuch bei der E-Stelle Rechlin talks about the trials with the C-3 injection - (C-3 Einsitzsprung), basically what it says is:
- 6 190s were used for trials starting 17 May 1943 and finishing in July 1943
- the engines were run at 2700/1.65ata with the C3 injection activated
- in all 32 hours of tests were done on the 6 machines
- power output at ground level was 2060PS
- speed gain ranged from 30 to 45kph depending on how the aircraft was configured
The table at the bottom of that page shows the results obtained for the six aircraft with the C3-Einsitzprung.
The article goes on to talk about engine temperatures and notes that two aircraft were run at 1.65ata even without the system running, but that for combat the system should be used.
The section after that talks about tests from 3 June 1943 by Focke Wulf on a A-5/U8 which obtained a speed boost of +37kmh at 200 meters altitude.
There is then a discussion about the tests done with the MW-50 system, these however only produce a boost of +16kph.
There is then a discussion about the C-3 system being fitted to operational F and G jabo's and the limitations on its use - only to be used under 1000 meters with the supercharger in first gear.
The most interesting section is the last. Basically it says that from July 1944 all A-8s got the C-3 injection system and that it could be operated without altitude restriction with earlier aircraft being able to be upgraded.
It says that in first supercharger gear the engine could be run at 1.58ata and in second at 1.65ata. The gain is speed was 22kph in first gear, 25kph in second and it could be run for ten minutes. The system could be used up to the rated altitude.
I'm sure one of the native speakers could do a far more polished and comprehensive job.
This has been my whole problem from the start. Fuel doesn't do that.Gille said:The diagrams on the second page of the article are from the Flugzeug Handbuchs and show the layout of the system.
As to how it works, I'm not an aircraft engine guru but AFAIK it works pretty much the same way as MW-50 except that fuel is used as the coolant instead of a methanol-water mixture. With MW-50 the mixture is sprayed on the fuel/air charge so as to reduce the temperature of that charge (by evaporation of the water, the methanol is just there as an anti-freeze) and thus to prevent detonation in the cylinders prior to proper combustion. This lets you run the supercharger on higher boosts that would otherwise be possible without detonation.
C3 injection works the same way except that fuel is used instead of MW-50. If an aircraft can be configured with MW-50 injection I don't see what is so hard about conceiving the same system save that you use fuel instead of a special mixture, its easier to set up because you don't need the special MW-50 tank.
I'm sure if MW-50 worked better in the 801D then the Germans would have used it, but their testing showed the C3 injection allowed higher boosts and gave greater speed.
No wonder I couldn't find it, it was used only on the ground attack F-8 variant Fw190 and is a completely different engine setup to that used on the fighter types from A-3 through to A-9. Obviously it appears on no blueprints or documentation for these aircraft. It is not the C3 injection system at all (all BMW801D-2's used C3 fuel and were sequentially or multipoint, direct injected), it is the boost-system used on that, low-altitude model. C3 fuel was used on all Fw-190's from the A-3 onwards due to higher compression ratios and supercharger gearing. All my source materiel has been accurate on this matter.The Fw 190F-8 was powered by a BMW 801 D-2 engine variant adapted for C3 (96 octane) fuel. An additional injector in the left supercharger inlet for emergency short term (10-15 min) engine power increase during flight under 1000 m altitude was standard equipment.
This is the run of the mill, basic engine fitted to all fighter models from the A-3 onwards, without boost.Beginning in the spring of 1942, series production of a more powerful engine version BMW 801D-2 that replaced previous versions in the Fw 190Fighter created a new plane version designated as Fw 190A-3. The increase in the BMW 801D-2 engine power (to 1730 kW) was due to a higher compression ratio and higher pressure two-speed compressor. A higher compression ratio and charging pressure made it necessary to use high-octane (96 octane) C3 fuel in place of B4 (87 octane) fuel.
And this booster system was usable under a wider variety of atmospheric-densities, because it cooled the cylinders to prevent predetonation at higher settings, which the F-8 low-altitude booster system did not. It altered the engine tuning.A new model with different equipment. Most important were parts of the MW 50 injection system, used for short term engine power boost. A cylindrical tank of 118 liters capacity was mounted in the rear fuselage. In an emergency, it could be used as additional fuel tank. Tank installation shifted the center of gravity backward and, as a cure, the under-fuselage mounted ETC 501 bomb rack was moved 20 cm forward. This rack became a standard from the A-8 model.