Compressor system having rotor with distributed coolant conduits and method

1. A compressor system comprising:

a housing having formed therein a gas inlet, a gas outlet, and a fluid conduit extending between the gas inlet and the gas outlet;

a rotor rotatable within the housing about an axis of rotation, the rotor having an axial direction associated with the axis of rotation and a circumferential direction associated with a rotating motion about the axis of rotation, and the rotor having an outer compression surface exposed to the fluid conduit, a plurality of inner heat exchange surfaces, and an outer body wall extending between the outer compression surface and the plurality of inner heat exchange surfaces;

the rotor further including a first axial end having a coolant inlet formed therein, a second axial end having a coolant outlet formed therein, and a coolant manifold fluidly connected with the coolant inlet; and

the rotor further including a plurality of coolant supply conduits having an axial and circumferential distribution, and each extending outwardly from the coolant manifold so as to supply a coolant to each of the plurality of inner heat exchange surfaces at a plurality of axial and circumferential locations, the rotor further including a plurality of coolant exhaust conduits each coupled with individual ones of the plurality of inner heat exchange surfaces, wherein separate flow paths are defined through the plurality of coolant supply conduits, plurality of inner heat exchange surfaces, and plurality of coolant exhaust conduits where the plurality of inner heat exchange surfaces extend between the plurality of coolant supply conduits and plurality of coolant exhaust conduits.

2. The system of claim 1 wherein the coolant manifold and the plurality of coolant supply conduits are formed in a one-piece section of the rotor body.

3. The system of claim 1 wherein the coolant manifold includes a coolant supply manifold, and the rotor further includes a coolant exhaust manifold.

4. The system of claim 3 wherein the plurality of coolant exhaust conduits having an axial and circumferential distribution and extending inwardly to the coolant exhaust manifold.

5. The system of claim 4 wherein the coolant supply manifold and the coolant exhaust manifold are overlapping in axial extent.

6. The system of claim 5 wherein the coolant supply manifold and the coolant exhaust manifold are coaxial.

7. The system of claim 1 wherein the outer compression surface forms a helical shape.

8. The system of claim 7 wherein the system includes a dual rotary screw compressor comprising a second rotor in parallel with the first rotor and intermeshed therewith.

9. The system of claim 1 wherein the plurality of coolant supply conduits include terminal nozzle orifices oriented to spray coolant onto the plurality of inner heat exchange surfaces.

10. A rotor for a compressor system comprising:

a rotor body defining a longitudinal axis extending between a first axial body end and a second axial body end, the rotor body having an axial direction associated with the longitudinal axis and a circumferential direction associated with a rotating motion about the longitudinal axis, and including an outer compression surface, a plurality of inner heat exchange surfaces, and an outer body wall extending between the outer compression surface and the plurality of inner heat exchange surfaces;

the rotor body further including a coolant inlet formed in the first axial body end, a coolant outlet formed in the second axial body end, and a coolant manifold fluidly connected with the coolant inlet; and

the rotor body further including a plurality of coolant supply conduits having an axial and circumferential distribution, and extending outwardly from the coolant manifold so as to supply a coolant to the plurality of inner heat exchange surfaces at a plurality of axial and circumferential locations, the rotor body further including a plurality of coolant exhaust conduits each coupled with individual ones of the plurality of inner heat exchange surfaces, wherein flow paths are defined through pairings of the plurality of coolant supply conduits, plurality of inner heat exchange surfaces, and plurality of coolant exhaust conduits where the plurality of inner heat exchange surfaces extend between the plurality of coolant supply conduits and plurality of coolant exhaust conduits.

11. The rotor of claim 10 wherein each of the first and second axial body ends includes a cylindrical shaft end, for rotatably journaling the rotor body in a compressor housing, and the outer compression surface extending axially between the first and second axial body ends and defining a helical shape.

12. The rotor of claim 11 wherein the plurality of inner heat exchange surfaces includes a plurality of axially and circumferentially advancing heat exchange surfaces each having an arcuate shape.

13. The rotor of claim 11 wherein the coolant manifold and plurality of coolant supply conduits are formed in a one-piece section of the rotor body having a uniform material composition throughout.

14. The rotor of claim 11 comprising a screw rotor where the outer compression surface includes a plurality of helical lobes in an alternating arrangement with a plurality of helical grooves.

15. The rotor of claim 10 wherein the coolant manifold includes a coolant supply manifold, and further comprising a coolant exhaust manifold overlapping in axial extent with the coolant supply manifold, and a plurality of coolant exhaust conduits having an axial and circumferential distribution and extending inwardly to the coolant exhaust manifold.

16. The rotor of claim 15 wherein some of the coolant supply conduits are positioned axially between coolant exhaust conduits and the coolant outlet, and some of the coolant exhaust conduits are positioned axially between coolant supply conduits and the coolant inlet.

17. The rotor of claim 15 wherein at least some of the coolant supply conduits pass through the coolant exhaust manifold.

18. A method of operating a fluid compressor comprising:

rotating a rotor within a compressor housing so as to compress a gas via impingement of an outer compression surface of the rotor on the gas, the rotor having an axial direction associated with an axis of rotation about which the rotor is rotated and a circumferential direction associated with the rotating the rotor about the axis of rotation;

conveying a coolant into a coolant manifold within the rotor, and from the manifold to coolant supply conduits within the rotor; and

spraying a plurality of inner heat exchange surfaces of the rotor with the coolant from the conduits at a plurality of axially and circumferentially distributed locations, so as to dissipate heat generated by the compression of the gas; and

wherein the conveying and spraying includes conveying and spraying a refrigerant in liquid form that undergoes a phase change within the rotor, and further comprising exhausting the refrigerant in gaseous form from the rotor.

19. The method of claim 18 wherein the exhausting of the refrigerant includes exhausting the refrigerant via a coolant exhaust manifold that has an axial extent overlapping with an axial extent of a coolant supply manifold supplying the plurality of coolant supply conduits.

20. The method of claim 18 which further includes flowing coolant through distinct flow paths defined by individual ones of the plurality of coolant supply conduits, plurality of inner heat exchange surfaces, and individual ones of a plurality of coolant exhaust conduits where the plurality of inner heat exchange surfaces extend between the plurality of coolant supply conduits and plurality of coolant exhaust conduits, and wherein the plurality of coolant exhaust conduits have an axial and circumferential distribution and extend inwardly to a coolant exhaust manifold.