Housing for a centrifugal fan, pump, or turbine

1. A fluid-flow system comprising:

a housing;

a rotor configured to cooperate with a fluid flowing through the housing, the rotor including at least one vane to drive or be driven by the fluid, the at least one vane having an active surface configured to cooperate with the fluid flowing through the housing, wherein the curvature of the active surface conforms to a logarithmic curve, the radius of the logarithmic curve unfolding at a constant order of growth when measured at equiangular radii; and

a shroud for guiding the fluid moving in association with the rotor, the shroud forming a portion of the housing and configured to promote vortical flow of the fluid through the housing, wherein the shroud includes an active surface configured to cooperate with the fluid flowing within the housing, the active surface including a logarithmic spiral.

2. The system of claim 1 , wherein the logarithmic spiral unfolds at a constant order of growth when measured at equiangular radii.

3. The system of claim 1 , wherein the rotor is a centrifugal rotor.

4. The system of claim 1 , wherein the rotor is an axial rotor.

5. The system of claim 1 , wherein the rotor has a flow characteristic intermediate a centrifugal rotor and an axial rotor.

6. A fluid-flow system comprising:

a housing;

a rotor configured to cooperate with a fluid flowing through the housing, the rotor including at least one vane to drive or be driven by the fluid, the at least one vane having an active surface configured to cooperate with the fluid flowing through the housing, wherein the curvature of the active surface conforms to a logarithmic curve, the radius of the logarithmic curve unfolding at a constant order of growth when measured at equiangular radii; and

a shroud for guiding the fluid moving in association with the rotor, the shroud forming a portion of the housing and configured to promote vortical flow of the fluid through the housing, wherein the shroud includes an active surface configured to cooperate with the fluid flowing within the housing, the active surface having a configuration conforming substantially to that of a logarithmic curve.

7. The system of claim 6 , wherein the logarithmic curve unfolds at a constant order of growth when measured at equiangular radii.

8. A fluid-flow system comprising:

a housing;

a rotor configured to cooperate with a fluid flowing through the housing, the rotor including at least one vane to drive or be driven by the fluid, the at least one vane having an active surface configured to cooperate with the fluid flowing through the housing, wherein the curvature of the active surface conforms to a logarithmic curve, the radius of the logarithmic curve unfolding at a constant order of growth when measured at equiangular radii; and

a shroud for guiding the fluid moving in association with the rotor, the shroud forming a portion of the housing wherein the internal surface of the shroud conforms to the stream lines of a vortex, the shroud configured to promote vortical flow of the fluid through the housing.

9. A fluid-flow system comprising:

a housing;

a rotor configured to cooperate with a fluid flowing through the housing, the rotor including at least one vane to drive or be driven by the fluid, the at least one vane having an active surface configured to cooperate with the fluid flowing through the housing, wherein the curvature of the active surface conforms to a logarithmic curve, the radius of the logarithmic curve unfolding at a constant order of growth when measured at equiangular radii; and

a shroud for guiding the fluid moving in association with the rotor, the shroud forming a portion of the housing wherein the internal surface of the shroud conforms in shape to the shape of a shell of the genus Trochus , the shroud configured to promote vortical flow of the fluid through the housing.

10. A fluid-flow system comprising;

a housing;

a rotor configured to cooperate with a fluid flowing through the housing, the rotor including at least one vane to drive or be driven by the fluid, the at least one vane having an active surface configured to cooperate with the fluid flowing through the housing, wherein the curvature of the active surface conforms to a logarithmic curve, the radius of the logarithmic curve unfolding at a constant order of growth when measured at equiangular radii; and

a shroud for guiding the fluid moving in association with the rotor, the shroud forming a portion of the housing, wherein the shroud substantially surrounds at least the perimeter of the rotor and provides a space between the inner surface of the shroud and a surface swept by an outer edge of the at least one vane during rotation of the rotor and wherein the space increases from a minimum cross-sectional area to an expanded cross-sectional area, the shroud configured to promote vortical flow of the fluid through the housing.

11. The system of claim 10 , wherein the space increases in area at a space-logarithmic ratio.

12. The system of claim 11 , wherein the space-logarithmic ratio increases at a constant order of growth when measured at equiangular radii.

13. The system of claim 10 , wherein the space includes an axial component relative to the rotor.

14. An axial rotor system comprising: opposed end walls;

side walls extending between the opposed end walls, wherein at least one side wall comprises an opening inlet concentric with a central axis;

a rotation path located between the side walls and having an outlet, the outlet being located substantially tangential to the rotation path;

a central hub rotatably supported by the housing; and

an axial rotor located between the side walls and within the rotation path, the axial rotor configured to rotate about the central axis, the axial rotor comprising a set of radial blades supported by the central hub, wherein the rotation of the axial rotor causes a vortical flow of fluid through the housing from the inlet to the outlet, the flow of fluid influenced by an internal face of the housing, the internal face of the housing comprising a continuous surface defined by the opposed end walls and the side walls, the internal face further comprising a curvature that corresponds to a logarithmic curve, wherein the radius of the logarithmic curve measured at equiangular radii unfolds at a constant order of growth.

15. The axial rotor system of claim 14 , wherein the cross-sectional area of the space between the rotation path and the internal face is of an increasing cross-sectional area about the rotation path and is of a maximum cross-sectional area at the outlet.

16. The fan housing system of claim 15 , wherein the cross-sectional area generally corresponds to a logarithmic curve, wherein the radius of the logarithmic curve measured at equiangular radii unfolds at a constant order of growth.

17. The axial rotor system of claim 16 , wherein the degree of the curvature that is in the plane that is transverse to the central axis is different from the degree of the curvature that is parallel to the central axis.

18. The axial rotor system of claim 15 , wherein the curvature is also in a plane that is parallel to the central axis.

19. The axial rotor system of claim 17 , wherein the curvature is in a plane that is transverse to the central axis.

20. A centrifugal rotor system comprising:

opposed end walls;

side walls extending between the opposed end walls, wherein at least one side wall comprises an opening inlet concentric with a central axis;

a rotation path located between the side walls and having an outlet, the outlet being located substantially tangential to the rotation path;

a central hub rotatably supported by the housing; and

a centrifugal rotor located between the side walls and within the rotation path, the centrifugal rotor configured to rotate about the central axis, the centrifugal rotor comprising a set of radial blades supported by the central hub, wherein the rotation of the centrifugal rotor causes a vortical flow of fluid through the housing from the inlet to the outlet, the flow of fluid influenced by an internal face of the housing, the internal face of the housing comprising a continuous surface defined by the opposed end walls and the side walls, the internal face further comprising a curvature that corresponds to a logarithmic curve, wherein the radius of the logarithmic curve measured at equiangular radii unfolds at a constant order of growth.

21. The centrifugal system of claim 20 , wherein at least one blade in the set of radial blades comprises a curvature that corresponds to a logarithmic curve, wherein the radius of the logarithmic curve measured at equiangular radii unfolds at a constant order of growth.

22. A rotor system comprising:

opposed end walls;

side walls extending between the opposed end walls, wherein at least one side wall comprises an opening inlet concentric with a central axis;

a rotation path located between the side walls and having an outlet, the outlet being located substantially tangential to the rotation path;

a central hub rotatably supported by the housing; and

a rotor located between the side walls and within the rotation path, the rotor configured to rotate about the central axis, the rotor comprising a set of radial blades supported by the central hub, wherein the rotation of the rotor causes a vortical flow of fluid through the housing from the inlet to the outlet, the flow of fluid influenced by an internal face of the housing, the internal face of the housing comprising a continuous surface defined by the opposed end walls and the side walls, the internal face further comprising a curvature that corresponds to the shape of a shell of the genus Trochus.

23. A rotor system comprising:

opposed end walls;

side walls extending between the opposed end walls, wherein at least one side wall comprises an opening inlet concentric with a central axis;

a rotation path located between the side walls and having an outlet, the outlet being located substantially tangential to the rotation path, a central hub rotatably supported by the housing; and

a rotor located between the side walls and within the rotation path, the rotor configured to rotate about the central axis, the rotor comprising a set of radial blades supported by the central hub, wherein the rotation of the rotor causes a vortical flow of fluid through the housing from the inlet to the outlet, the flow of fluid influenced by an internal face of the housing, the internal face of the housing defining a space of a generally helical formation that comprising a curvature that corresponds to a logarithmic curve, wherein the radius of the logarithmic curve measured at equiangular radii unfolds at a constant order of growth.