Optimum Forced Flow Through A Duct

[Le Chaud Lapin]

Hi All,

Please execuse the bad terminology which will undoubtedly ensue as I
am new to this field.

I was just watching a show on TV about steam turbines. I have always
wondered, from an engineering point of view, about the dynamics and
difficulties of getting the fluid that turns the turbine, to, indeed,
turn the turbine, and not simply bypass. I imagine there is some
efficiency factor that indicates how well the pressure of the fluid
against the turbine actually results in turning the turbine and not
worming its way out.

Question 1:
Where should I look to find out more details about this?

Question 2:
Suppose I have the objective of making a blower, the kind one would
buy at the local harware store. If the diameter of my nozzle is
reduced to say, only 1 centimeter, what mechanism should I use for the
engine of the blower to get maximum exit velocity of the air? I am
allowed to use expensive components, but the generation of pressure
must be built using a rotary mechanims only. At no time will I be
able to use a piston-type mechanism, for example

Hope I am not making too much non-sense.

-Le Chaud Lapin-