Counter rotating helico-axial pump

1. A counter rotating helico-axial pump comprising:

(a) an inner rotor comprising one or more outwardly extending helico-axial impeller vanes;

(b) a hollow outer rotor comprising one or more inwardly extending helico-axial impeller vanes;

(c) a single driving device configured to drive the inner rotor or the hollow outer rotor; and

(d) a force transmission coupling joining the inner rotor and the hollow outer rotor and configured to permit rotation of the inner rotor and hollow outer rotor in opposite directions;

wherein at least a portion of the inner rotor is disposed within the hollow outer rotor, and wherein the inner rotor, the hollow outer rotor and the helico-axial impeller vanes define a fluid flow path, and wherein the inner rotor and hollow outer rotor are configured such that at least some of adjacent helico-axial impeller vanes are configured to rotate in opposite directions.

2. The counter rotating helico-axial pump according to claim 1 , wherein the driving device drives the inner rotor.

3. The counter rotating helico-axial pump according to claim 1 , wherein the driving device drives the hollow outer rotor.

4. The counter rotating helico-axial pump according to claim 1 , wherein the force transmission coupling mechanically joins the inner rotor and the hollow outer rotor.

5. The counter rotating helico-axial pump according to claim 4 , wherein the force transmission coupling is a planetary gear assembly.

6. The counter rotating helico-axial pump according to claim 1 , wherein the force transmission coupling magnetically joins the inner rotor and the hollow outer rotor.

7. The counter rotating helico-axial pump according to claim 6 , wherein the force transmission coupling is a magnetic gearbox assembly.

8. The counter rotating helico-axial pump according to claim 1 , wherein there is no housing assembly.

9. The counter rotating helico-axial pump according to claim 1 , not comprising a pump housing.

10. The counter rotating helico-axial pump according to claim 9 , wherein the pump housing comprises an axial fluid inlet and axial fluid outlet.

11. A counter rotating helico-axial pump comprising:

(a) an inner rotor comprising one or more outwardly extending helico-axial impeller vanes;

(b) a hollow outer rotor comprising one or more inwardly extending helico-axial impeller vanes;

(c) a single driving device configured to drive the inner rotor or the hollow outer rotor; and

(d) a force transmission coupling joining the inner rotor and the hollow outer rotor and configured to permit rotation of the inner rotor and hollow outer rotor in opposite directions;

wherein at least a portion of the inner rotor is disposed within the hollow outer rotor, and wherein the inner rotor, the hollow outer rotor and the helico-axial impeller vanes define a fluid flow path, and wherein the inner rotor and hollow outer rotor are configured such that at least some of adjacent helico-axial impeller vanes are configured to rotate in opposite directions, and wherein the inner rotor, the hollow outer rotor are disposed within a pump housing.

12. The counter rotating helico-axial pump according to claim 11 , wherein at least some of adjacent helico-axial impeller vanes are configured to rotate in opposite directions, and at least some of at least some of adjacent helico-axial impeller vanes are configured to rotate in the same direction.

13. The counter rotating helico-axial pump according to claim 11 , wherein the driving device drives the inner rotor.

14. The counter rotating helico-axial pump according to claim 11 , wherein the driving device drives the hollow outer rotor.

15. The counter rotating helico-axial pump according to claim 11 , wherein the force transmission coupling mechanically joins the inner rotor and the hollow outer rotor.

16. The counter rotating helico-axial pump according to claim 15 , wherein the force transmission coupling is a planetary gear assembly.

17. The counter rotating helico-axial pump according to claim 11 , wherein the force transmission coupling magnetically joins the inner rotor and the hollow outer rotor.

18. The counter rotating helico-axial pump according to claim 17 , wherein the force transmission coupling is a magnetic gearbox assembly.

19. The counter rotating helico-axial pump according to claim 11 , wherein the pump housing comprises an axial fluid inlet and axial fluid outlet.

20. The counter rotating helico-axial pump according to claim 11 wherein the force transmission coupling is configured to allow flow of a working fluid through a fluid flow path defined between the force transmission coupling and an inner wall section of the hollow outer rotor.

21. A counter rotating helico-axial pump comprising:

(a) an inner rotor comprising one or more outwardly extending helico-axial impeller vanes;

(b) a hollow outer rotor comprising one or more inwardly extending helico-axial impeller vanes;

(c) a single motor configured to drive the inner rotor; and

(d) a force transmission coupling mechanically joining the inner rotor and the hollow outer rotor and configured to drive the hollow outer rotor in a direction of rotation opposite that of the inner rotor;

wherein at least a portion of the inner rotor is disposed within the hollow outer rotor, and wherein the inner rotor, the hollow outer rotor and the helico-axial impeller vanes define a fluid flow path, and wherein the inner rotor and hollow outer rotor are configured such that adjacent helico-axial impeller vanes are configured to rotate in opposite directions, and wherein the inner rotor, the hollow outer rotor, and the motor are disposed within a pump housing having an axial fluid inlet and an axial fluid outlet.