design solution needed

[franklyn]

What curve of a centrfugal impeller vane will produce the greatest exit velocity for incompressible fluids? If the design constraint limits the vane's surface to be parallel with the rotational axis, this will produce one result. If however the width of the vane also tapers radially, other solutions are possible! Curvature in three dimensions, or a helical pitch is also a consideration.
The application will be for a device within which liquid circulates as in a liquid ring compressor - but for a different purpose.

 

[insideman]

Greatest velocity is produced by forward curved impellers.

 

[franklyn]

Thanks, I knew that "insideman".
Not being skilled in the art, I'm looking for an idealized optimal solution mathematically described.
I know this is a horrific problem in fluid dynamics,
but surely something close to an answer must have been
found.

 

[sprintcar]

Hydraulic design in part computer and part witchcraft - most pump companies have a few specialist who just design what you're looking for. Since each application is different it is a case by case exercise.

Velocity is really a function of impeller tip speed determined by diameter and rpm. The amount of Energy (ie head) transmitted into the fluid is determined by the vane length and shape. Twisted vanes usually have more surface (length) than straight, radial vanes thus imparting more energy into the working fluid.

Now if you could explain all those electrical mysteries to me...... Keep the wheels on the ground
Bob
showshine@aol.com

 

[franklyn]

Thanks so much "sprintcar"
That does confirm my suspicion that impeller design remains
an open question. I continue to research sources in the public domain gleaned from other threads in this forum.

Electric mysteries are not much better. There is still much
debate about which model of electromagnetism is more correct
i.e. Biot-Savart, Lorentz, Grassmann, or Ampere, Weber.
Maxwell and others not withstanding.