Lighter weight, higher strength materials are definitely in order for
reciprocating engine
components. Remember, the piston and connecting rod come to a complete (albeit
very brief)
halt twice in every revolution. The lighter these components are, the less
stress they and
their supporting/connecting components are subjected to (Force = Mass x
Acceleration).
Gary McCormick
San Jose, CA
R Haug wrote:
> Adam Bradley wrote:
>
> > That is, is the limiting factor of our engine RPM the stroke or
> > something else?
>
> I remember reading something about the design of older Ferrari engines a
> few years back. They tried to keep the piston and rod velocity below 4000
> feet per second. If you increase the stroke of the engine, you effectively
> increase the velocity of the piston and rods. If you exceed this limit
> then something will come loose (read that as break).
> Many of those high revving F1 engines have relatively short strokes. The
> use of titanium probably helps significantly as well. They may even use
> other high tech materials to withstand the extreme rpms.
> I thought they were going to replace the valve springs with solenoids to
> actuate the valves so they could control opening and closing more
> accurately at high rpms. I could be wrong. They run 2 - 3 times the rpm
> capability of our engines.
> Bob
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