Quote:
Originally Posted by serialk11r
The initial benefit I saw was that you could use a CVT or electric motor to drive the supercharger and then be able to control engine output in a very simple and possibly responsive way. However having an electric motor controlling it is going to be complicated anyways, and a CVT probably doesn't change ratios quickly enough to have any sort of acceptable response.
The most efficient way to try to get energy back from the intake would be with an actual turbine, not a compressor run backwards, but at ~70% max efficiency + friction losses + varying performance across rev range it's hard to justify the cost.
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CVT is already a ~20ish % loss in energy to friction losses in most cases.
If I gather what you're saying correctly, you intend to replace the throttle plate with what amounts to a variable restriction that generates torque based on air flow through the intake under vacuum?
If that's the case, abandon hope all ye who enter here. If I remember correctly, the most energy that can be theoretically extracted from any source which requires fluid movement (i.e. wind) is less than 50% of the overall energy. Wind turbines, for example, would not be able to harvest more than 50% of the energy of the wind, because doing so would necessitate the wind to literally stop at the turbine face, returning zero energy for all it's effort.
So now that you're taking about 50% of the energy of a vacuum (oh, no), and putting it through CVT, you're looking at a (conservatively) 15% loss, leaving you with 85% of the original 50%, leaving you with 42.5%.
Let's say your vacuum under full load is sufficient to provide 10 lbft of torque via air movement - you can now only extract a maximum of 5, and after the loss, redeliver 4.25 to the crankshaft, all things theoretically at their best values.
Reconsider, however, that you're technically introducing a new restriction to the intake, increasing the vacuum and, by relation, the subsequent load on the engine, causing more "work" to extract the "Work" that you intended to redeliver to the crank.
If that's not what you were alluding to, please explain further.