I think the piston speed gets to maximum velocity midway between tdc & bdc and will be stationary at the point of which the piston changes it's direction of travel. Now the time elapsed depends on the distance of the crankpin to the flywheel center, ie a long stroke and large flywheel the piston would be traveling slower to the opposite end of the scale -short stoke small flywheel. Oh what the f*** does it matter?
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Im not sure it occurs at half stroke. Half stroke certainly doesn't equate to 90 degrees rotatation.
http://www.epi-eng.com/piston_engine_technology/piston_motion_basics.htmIt's difficult to argue that at tdc and bdc the piston speed isn't at zero, but my point was that the length of time it is at zero appears also to be zero! For the reasons I've put forward (which may be wrong).
The position of maximum velocity, which equates to zero acceleration, is just as strange. That too apparently occurs for zero length of time. Regardless of rpm.
Anywhere on a pure sine wave will occur for zero length of time, because there are no straight portions on a sine wave. By definition, anything occurring as a sine wave is constantly changing so it is never at a value for any time! Weird. It seems to be the nature of geometry. But you can see the phenomenon everywhere where positional contrivances are in place. Distance measurement, for example, and even time itself. For example, how short is the present? Zero! There is no present. So what are we experiencing, the past or the future? Weird ain't it?
Or is it just me.....
