Re: economy of scale in rockets: how?

On Sat, 2004-11-06 at 20:43, Bill Clawson wrote:
> My information is a bit rusty, but doesn't the engine
> efficiency also increase with size?  I think this is
> related to gas flow & resistance in the nozzle & bell,
> in addition to loss of heat from the working fluid
> into the engine walls.  I assume there is such a thing
> as too big of an engine, but there is also such a
> thing as too small of an engine, no?

	Yes, but it's a second or third order effect. Basically, the boundary
layers form a smaller part of the total flow area of the engine, so you
lose less to them. There is such a thing as too small of an engine, due
to square-cube law induced cooling problems. The only limits on engine
size are how far you are willing to let the sound travel, and how much
patience you have for fixing stability issues.

	-p