Just a blue-sky thought for discussion (and to jump-start prior art):
We all know that torsional vibration is a major issue that you have to address in any new PSRU/engine/prop combination. We also (most of us, at least) know that TV can be complicated, counterintuitive, and expensive to address. You can toss some major engineering effort into moving power between different RPMs without breaking your weight budget.
Just for the sake of discussion, what if you had such complete control over your engine that you could detect the resonances that indicate destructive forces, and adjust the operating parameters to damp them?
I would guess that it takes more than conventional spark timing and mixture control to get ahead of the curve of something like that. But what if you had individual control over every spark plug and every fuel injector? And what if, on top of that, you had individual control over every intake valve and every exhaust valve?
http://www.autoblog.com/2016/11/21/koenigsegg-freevalve-engine-qoros-qamfree/
What I'm thinking is that you could detect TV conditions, and when you see a resonance that approaches destructive levels, you could jigger the valve, ignition, and fuel injection timing so that the resonance damps out instead of reinforcing itself.
Thoughts?
--Bob K.
We all know that torsional vibration is a major issue that you have to address in any new PSRU/engine/prop combination. We also (most of us, at least) know that TV can be complicated, counterintuitive, and expensive to address. You can toss some major engineering effort into moving power between different RPMs without breaking your weight budget.
Just for the sake of discussion, what if you had such complete control over your engine that you could detect the resonances that indicate destructive forces, and adjust the operating parameters to damp them?
I would guess that it takes more than conventional spark timing and mixture control to get ahead of the curve of something like that. But what if you had individual control over every spark plug and every fuel injector? And what if, on top of that, you had individual control over every intake valve and every exhaust valve?
http://www.autoblog.com/2016/11/21/koenigsegg-freevalve-engine-qoros-qamfree/
What I'm thinking is that you could detect TV conditions, and when you see a resonance that approaches destructive levels, you could jigger the valve, ignition, and fuel injection timing so that the resonance damps out instead of reinforcing itself.
Thoughts?
--Bob K.