Can someone explain briefly how EMU PRO calculates injection timing for rotary engines?
There is SOI and EOI parameters. Which to use? How it calculates start and and injector operation and etc.
Explanation by deggrees would be awesome.
Looking forward for anyone.
Hi,
Injection timing always works the same way, no matter the engine type.
You have to select which control method you want to use. You either have the end or start of the injection at a constant crankshaft angle. The default option is the end of injection, and that’s the recommended method for most port injection engines. It allows the ECU to always finish the injection before the intake port gets closed.
Another element is the injection angle table, which has values in crankshaft degrees before the power stroke TDC. Assuming the method is end-of-injection, a value of 180 will mean that the injection will always end at 180 degrees before the power stroke TDC of that cylinder.
I am unfamiliar with the details of the rotary engine, so I can’t help you with exact numbers, but you can check when the intake port is closing relative to the TDC. This can be your starting point because injecting fuel later (at lower angles) is not beneficial. Injecting fuel after the port has closed means the fuel has to wait for the next cycle, and other cylinders can steal the mixture.
Optimization of the injection angle is done by observing lambda with open-loop fueling. If changing the injection angle makes the lambda leaner (without changing the injected fuel volume), that means the combustion is more complete, which is better.