Vane shape in a closed impeller
Vane shape in a closed impeller
(OP)
Hi everybody
I would be thankful if you let me know your viewpoint about the following
Today at a pump factory I saw a pump that had vanes with triangle cut. i.e., instead of having common straight/oblique cut it had a forward tringle shape. see the attached file where the red lines show the cut schematically.

do you know what is the reason for such a design? usually trimming is done such a way to increases the distance between the vane tip and the casing (the so-called gap B) via a backward triangle cut. However with such a cut, the distance between the center of the vane and the casing does not change.
Best
I would be thankful if you let me know your viewpoint about the following
Today at a pump factory I saw a pump that had vanes with triangle cut. i.e., instead of having common straight/oblique cut it had a forward tringle shape. see the attached file where the red lines show the cut schematically.

do you know what is the reason for such a design? usually trimming is done such a way to increases the distance between the vane tip and the casing (the so-called gap B) via a backward triangle cut. However with such a cut, the distance between the center of the vane and the casing does not change.
Best
RE: Vane shape in a closed impeller
Johnny Pellin
RE: Vane shape in a closed impeller
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)