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Old 03-07-2012, 07:26 PM   #686
serialk11r
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Quote:
Originally Posted by Want.FR-S View Post
Are you confusing about where the force is applied? We all know that the explosion in the chamber *push* the piston, and then rod to make the crank rotate. Now you are telling me the rod transmits force to the piston to make it move? That is complete opposite to this.

For one thing, Newton's third law, forces are mutual. Only during the expansion stroke does the piston see a net force downward, in every other stroke yes in fact the rod is what is moving the piston.

[second paragraph was irrelevant, not going to say anything about it]

This is basic physics. What does this have to do with increasing rod length?
The piston's net acceleration is in a straight line, but the rod transmits force in the direction of its length as the wrist pin and crank pins are free to move, so there is almost always a sideloading force. A longer rod decreases the angle at any crank position, and decreases the total force. This is basic physics/geometry.
Okay I will attempt to address this post. Responses in bold.
Oh sorry, just noticed, the first post does point out a valid mistake, sorry about that, now it's fixed.

Crank angle and time are interchangeable at constant speed, please don't get nitpicky now. And sorry I couldn't resist being smart on that last comment, but please...

Last edited by serialk11r; 03-08-2012 at 05:04 PM.
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