Quote:
Originally Posted by Old Mechanic
I read somewhere that the peak BSFC on the lean burn insight motor was close to 49%.
regards
Mech
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49%?
That's an enormous number.
But a hybrid does not need to be a series hybrid to keep the engine at a constant load. I am building MIMA expressly because it will allow me to stay in lean burn most of the time.
Consider the Prius:
The Prius' Atkinson cycle engine, with a CVT and throttle-by-wire, delivers within 8% of peak BSFC, as long as load is >= 25% of maximum load. The Prius ought have an ICE just large enough to allow high-speed crusing on the ICE alone, and an electric motor large enough to give the car quick acceleration. If the load falls to less than 25% of maximum, the ICE should either be used to recharge the batteries, or it should shut off and allow the electric motor to propel the car.
A series hybrid drivetrain would need to be more than 92% efficient to outperform this arrangement, and that is the problem with series hybrids.