[singhg5]

Looks like there isn't much going on in the Forum, picked up a couple of videos of what actually happens inside an engine. Combustion, piston and valve movement in real life. These are old videos but interesting to see them again.

Combustion inside Engine

https://www.youtube.com/watch?v=UvmBLqjaZxY

Valves of a BMW at 14,000 rpm

https://www.youtube.com/watch?v=vcyT18qk8ls

Overhead cam rotation and valve train of BMW at ridiculously fast speed - 118 rotations per second ! Our eyes cannot even see so fast !

https://www.youtube.com/watch?v=nsa6kq-qqIE

[Arizoni]

It is rather incredible that all of those parts are moving just as far at those high speeds as they do when the engine is barely turning and they don't fly apart.

To me, that is even more impressive than the gas turbine engines I was involved with designing.

One of the gas turbine auxiliary power engines that is in almost every mid-sized commercial passenger jet flying now runs at a speed of around 700 revolutions per second.  That's 42,000 rpm, but it is just spinning.

Its parts don't go from stationary thru their full movement and come to a stop again where they started from like a piston at 233 times per second or the cam followers and valves at 117 times per second at 14,000 rpm.

Let's not forget the F-1 engines a few years ago that were running at 16,000-18,000 rpm's during a 2 hour race either.

Pretty amazing. 

[The Old Coot]

"One of the gas turbine auxiliary power engines that is in almost every mid-sized commercial passenger jet flying now runs at a speed of around 700 revolutions per second.  That's 42,000 rpm, but it is just spinning."

That's why almost every ship has gone to turbines and a lot of Navy ships to gas turbines. The old piston  type diesels and steam jobes just beat a ship to death, They could never push a warship to 40+ knots.