what are the types of forces acting on the piston during the power stroke (the
volume in the cylinder is expanding and combustion has occured) when the piston has moved
half its total travel away from top dead center position?
When the piston is halfway down, the rod is at it'* most extreme angle in relation to the bore. At this point during the power stroke, the rings are taking the most stress. I'm not too sure how you would get the force though..
A small portion of the force will be the piston moving through the oily crank case air. The crank case is slightly pressurized too due to blow-by. Although alot of the pressure is bled off through PCV..
Thats all I have for now.