Trimable impeller device and system
An impeller includes a hub and a plurality of blades. Each blade extends out from the hub. The impeller has an original diameter defined by respective tips of the plurality of blades. Each blade includes a central axis, a leading edge, a trailing edge, an original profile, and a plurality of trim profiles. The original profile has an outside portion and a trailing portion. The outside portion has an angle within a range of about 40° to about 90° from the central axis and the trailing portion having an angle within a range of about 10° to about 50° from the central axis. A first selected trim profile of the plurality of trim profiles extends along a first line parallel to the outside portion and a second line parallel to the trailing portion.
1. A method of trimming an impeller comprising the steps of:
providing the impeller, the impeller comprising:
a hub; and
a plurality of blades, each blade extending out from the hub, the impeller having an original diameter defined by respective tips of the plurality of blades, wherein each blade includes:
a central axis;
a leading edge;
a trailing edge; and
a first profile having an outside portion and a trailing portion, the outside portion having an angle within a range of 40° to 90° from the central axis and the trailing portion having an angle within a range of 10° to 50° from the central axis; and
trimming the impeller to a second profile comprising the steps of:
cutting each blade along a respective first line parallel to the outside portions,
cutting each blade along a respective second line parallel to the trailing portion, and
intersecting the first line and the second line at a chord length from the leading edge, wherein the chord length is defined by the following equation:
C=− 0.02* D 2 +0.8* D− 6.2 Eq. 1
wherein C is the chord length and D is a diameter of the impeller defined by respective tips of the plurality of blades generated by cutting along the first line.
2. The method according to claim 1 , wherein the outside portion has an angle of 85°±10° from the central axis and the trailing portion has an angle of 30°±10° from the central axis.
3. The method according to claim 1 , wherein the impeller further includes a respective flow accelerator disposed on each blade and each respective flow accelerator being a flap extending from a portion of the trailing edge proximal to the hub.
4. The method according to claim 3 , wherein the flow accelerators extend from the respective trailing edges at the same angle or at a steeper angle with respect to a horizontal line than a hub chord angle of each respective blade.