At one time it was referenced as "Battle Emergency Power Boost", and with overdrive to the supercharger , more fuel, and a lot of spark advance the engines certainly did put out more power. And the water kept them from blowing up. Perhaps water injection alone can improve performance or efficiency some, but not nearly as much.
It can, but only in pretty specific situations. Modern computer-controlled engines pretty much guarantee that those situations never arise, so adding water injection to such an engine without extensive reprogramming of the computer generally leads to worse performance and eventual engine damage.
Diesel pulling tractors also inject some water in the exhaust stream between the turbochargers, depending on the class they pull in they can have 2 or more in series. The water injected there makes steam to increase the out put of the turbo.
Are you claiming that the supercharger drive was variable? That's what it sounds like, at least to me. I'd like to see the basis of that if that is what your saying.
The reference was to a TURBO-supercharger, NOT a belt driven one. They are totally different things. The TURBO-supercharger is driven by the exhaust stream pressure and flow, not by the wide belt from the crankshaft pulley. I can see that adding water to that exhaust stream would add to the energy recovery effectiveness of the turbine. A belt driven supercharger would not make a lot of sense on a typical low-reving diesel engine, because they need to spin very fast..
First time I've heard of a Turbo-Supercharcher... I'm only familiar with Turbochargers and Superchargers, with the former being driven by the engine's exhaust gases and the latter directly by a belt.
Turbocharger is a contraction of turbo-supercharger. The term has been around for many years, and it was used by folks specifying engine components for use on oil rig engines..
I don't think this would be the reason for water injection there. The driven side of the turbo captures unused energy in the exhaust. Injecting water into the exhaust ahead of the turbo would diminish the returns by sucking up energy, changing water from liquid to gas is endothermic. Perhaps they are injecting water to keep temps down to a level that won't destroy the turbo?
If you're referring to a centrifugal supercharger, such as those made by Paxton, a gearbox can make up for lack of crankshaft speed. There are two reasons, that I'm aware of, superchargers aren't used much on 4-stroke diesels (common on 2-stroke diesels). First it's not efficient. It takes a lot of power, from the crankshaft, to run a mechanically driven supercharger. That's more fuel burn and more stress on the engine. Turbos recapture unused energy in the exhaust so you don't have the same penalty with a turbo. Secondly roots type superchargers heat the air A LOT, and hot air is less dense, which means less power. Injecting water or methanol can cool the air and bring density back, but that's a lot of extra stuff for a daily driver or commercial engine. Gale Banks has an excellent series where he covers some of this. In this video specifically he clamps a big roots blower to a diesel engine and shows, with data, why it doesn't work very well. The rest of the series is an excellent watch if you have the time:
Turbosupercharger is an older name (though still used in some contexts) for what we usually call just a turbocharger these days. It was originally known as a turbine-driven supercharger, which became turbosupercharger, which became turbocharger.
While that says they were invented before WW2, I was wanting to know about one used during the war on an airplane, since mrbill said he investigated their use in an air craft of that era.
Taht would be so in a single turbo use. But diesel tractors and trucks in some classes of pulling can have as many as 4 of them in series, with both the turbine and compressor in series. They inject the water in the down stream exhaust, between turbines to keep up the pressure. If you see one of the tractors in a pull, they start to spool up the turbos on the starting line and a flame shoots out of the stack then the water starts to get injected to keep the final turbine producing high out put. Since the last turbo in the series is the least powerful, it's compressor is the first boost stage.
That is what mrbill was trying to say when he talked about the aircraft engines. In pulling some classes don't allow inter cooling so they inject water into the in coming air.
No. The water and nitrous will both get burned in the combustion before it would ever make nitric acid. The nitrous it's self adds both oxygen and air charge cooling all by it's self, no water needed. But you do need to add extra fuel with nitrous or burn down the piston tops.
Nearly all combat aircraft in WWII used forced induction. Fighters typically used multistage, multispeed superchargers because they didn't have the room to accommodate the piping needed for interstage cooling of the turbochargers. Bombers and a few of the larger fighters generally used both types in series. Some German aircraft, including some models of the Bf-109 and Fw-190, used continuously variable (over a fairly wide range) superchargers that utilized fluid power couplings to drive them.
The ME-109 Superchargers were ingenious, and way ahead of their time. That entire airframe remained relevant for a very long time.
The cannon was NOT inside the engine. The cannon sat behind the engine with the barrel extending into a blast tube that was located between the two banks of engine cylinders (it was V-block engine). The blast tube then extended through the propeller shaft, which was offset from the engine crankshaft by the propeller gear box.
The cannon was inside the engine. They called it a Motorkanone.
