The two-stroke Diesel engine has a better chance as a motor vehicle engine than the two-stroke, petrol inlet manifold injection engine does, because the scavenging can be more effective. There is not the danger of blowing out unburnt air-fuel mixture through the exhaust system. Apart from that, no engine-oil can then find it's way into the exhaust gas. The two-stroke diesel direct fuel injection engines has better chances as vehicle engine than the two-stroke petrol-intake manifold injection engine because the flushing can be more effective. There is no danger to dismiss unused air-fuel mixture out of the exhaust system into the environment. Moreover, no engine oil reaches the exhaust gas.
In contrast to the general opinion, this engine does have valves and an oil-sump like the four-stroke engine. Nonetheles, it manages to compress or work and to exhaust or take in, all during one rotation of the crankshaft. To do this, it needs exhaust valves and the charging, in this case, several gigantic turbo-chargers. If the piston, on it's way down, opens the inlet ports, then fresh air, under high pressure, blows the exhaust gas out. If the exhaust valves now close a little earlier than the inlet ports do through the piston, a compression can already develop, which, through the rising piston, provides sufficient pressure for the combustion of fuel. Instead of the mixture-lubrication like in two-stroke motorcycles, this engine has pressure circulation lubrication, by the way, from oil-tanks which have a capacity of up to 100.000 liters. A complete oil-change is unheard of. After the oil has been accordingly chemically analysed certain parts of the oil are replaced.
This combustion method is found in, e.g., large marine Diesel engines which have a bore of approx. 1 meter and a stroke of approx. 2,5 meters giving the individual cylinder a capacity of almost 2 m³. At the low engine speeds of around 100 RPM, any number of cylinders is basically possible. At the moment they have up to 12 - 14. The performance is, with a 52% efficiency factor right now, just above the 100.000 hp limit. The biggest advantage is the maximisation of the cargo-capacity through the highest possible performance/torque installed in the smallest possible space.
One could easily image, that a motor vehicle engine would be used to start these giants. In reality however, with 30 bar pressure in several containers (starting air-bottles) sufficient energy is on tap for a maximum of fifteen starts. Indeed, this is also necessary because the ship has no gearbox, a 'reverse gear' is achieved by stopping the engines and restarting them in the reverse rotation. 01/13
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