Quote:
Originally Posted by WhiteFox
Apologies but never said RPM said rotational speed (and was referring to the bending speed) regardless it’s a better drive shaft and was removed late 2018.
|
Yes you did - “
Carbon Drive Shaft which was to
reduce weight and
rotational speed.” Rotational speed is rot/s, rad/s, rpm,…
Ok but your statement is still incorrect. The critical bending speed, which is the rotational velocity of a shaft that excites the out-of-plane primary lateral bending mode of the shaft (i.e., an instability/bifurcation point is reached, similar to flutter and buckling), has to INCREASE, not decrease/reduce, to be able to use a one-piece driveshaft. A properly designed CFRP driveshaft’s critical bending speed is higher than a steel driveshaft’s critical bending speed. BMW had to add a central support to the two-piece steel driveshaft. In this application of CFRP does not “reduce” the “rotational speed” of the driveshaft.