Volute for a centrifugal compressor

1. A volute for use in a centrifugal compressor including an impeller, the volute comprising:

a housing defining a central aperture, an inlet channel, and a fluid collecting channel, the central aperture adapted to receive the impeller such that the impeller discharges a fluid to the inlet channel, the inlet channel directing the flow to the collecting channel;

a discharge portion coupled to the housing and including a discharge passage in fluid communication with the collecting channel to discharge the fluid; and

a tongue portion disposed between the collecting portion and the discharge portion and operable to separate the fluid into a first flow that flows through the collecting channel and a second flow that flows through the discharge passage, wherein the tongue includes a leading edge that includes a fillet, and wherein the tongue defines a first wall portion and a second wall portion, and wherein the fillet defines a fillet size that varies between the first wall portion and the second wall portion.

2. The volute of claim 1 , wherein the housing includes a first housing portion and a second housing portion that cooperate to define the inlet channel and the fluid collecting channel.

3. The volute of claim 2 , wherein the discharge portion and the tongue portion are integrally-formed as a single piece with the second housing portion.

4. The volute of claim 1 , wherein the fluid collecting channel has a first cross-sectional area at a first angular position and a second cross-sectional area at a second angular position, the cross-sectional area increasing non-linearly between the first angular position and the second angular position.

5. The volute of claim 1 , wherein the discharge passage is frustoconical and wherein the cross-sectional area near an inlet is smaller than the cross-sectional area near an outlet.

6. The volute of claim 1 , wherein the tongue defines a first wall portion, a second wall portion and a central portion, and wherein the tongue is shaped such that the central portion is positioned downstream of the first wall portion and the second wall portion.

7. A volute for use in a centrifugal compressor including an impeller, the volute comprising:

a housing defining a central aperture, an inlet channel, and a fluid collecting channel, the central aperture adapted to receive the impeller such that the impeller discharges a fluid to the inlet channel, the inlet channel directing the flow to the collecting channel;

a discharge portion coupled to the housing and including a discharge passage in fluid communication with the collecting channel to discharge the fluid; and

a tongue portion disposed between the collecting portion and the discharge portion and operable to separate the fluid into a first flow that flows through the collecting channel and a second flow that flows through the discharge passage, wherein the tongue defines a first wall portion, a second wall portion and a central portion, and wherein the tongue is shaped such that the central portion is positioned downstream of the first wall portion and the second wall portion, and wherein the central portion is positioned to define an angle between a first radial line that passes through the first wall portion and the second wall portion, and a second radial line that passes through the central portion, wherein the angle is between about 15 degrees and 30 degrees.

8. The volute of claim 7 , wherein the angle is about 25 degrees.

9. A volute for use in a centrifugal compressor, the volute comprising:

a first housing portion;

a second housing portion coupled to the first housing portion to define an inlet channel and a fluid collecting channel, the fluid collecting channel having a first cross-sectional area at a first angular position and a second cross-sectional area at a second angular position, the cross-sectional area increasing non-linearly and continuously between the first angular position and the second angular position the first angular position and the second angular position disposed at opposite ends of the collecting channel such that the first cross-sectional area is the smallest cross-sectional area and the second cross-sectional area is the largest cross-sectional area of the collecting channel; and

a discharge portion coupled to the housing and including a discharge passage in fluid communication with the collecting channel.

10. The volute of claim 9 , further comprising a tongue portion disposed between the housing and the discharge portion and operable to separate the fluid into a first flow that flows through the collecting channel and a second flow that flows through the discharge passage.

11. The volute of claim 10 , wherein the discharge portion and the tongue portion are integrally-formed as a single piece with the second housing portion.

12. The volute of claim 10 , wherein the tongue includes a leading edge that includes a fillet.

13. The volute of claim 12 , wherein the tongue defines a first wall portion and a second wall portion, and wherein the fillet defines a fillet size that varies between the first wall portion and the second wall portion.

14. The volute of claim 10 , wherein the tongue defines a first wall portion, a second wall portion, and a central portion, and wherein the tongue is shaped such that the central portion is positioned downstream of the first wall portion and the second wall portion.

15. The volute of claim 14 , wherein the central portion is positioned to define an angle between a first radial line that passes through the first wall portion and the second wall portion, and a second radial line that passes through the central portion, wherein the angle is between about 15 degrees and 30 degrees.

16. The volute of claim 15 , wherein the angle is about 25 degrees.

17. The volute of claim 9 , wherein the discharge passage is frustoconical and includes an inlet and an outlet, and wherein the cross-sectional area near the inlet is smaller than the cross-sectional area near the outlet.

18. A volute for use in a centrifugal compressor including a diffuser, the volute comprising:

a housing defining a central aperture, an inlet channel, and a fluid collecting channel, the housing adapted to receive the diffuser within the central aperture and to receive a discharge fluid at the inlet channel, the inlet channel directing the flow to the collecting channel;

a discharge portion coupled to the housing and including a frustoconical discharge passage in fluid communication with the collecting channel to discharge the fluid, the discharge passage having an inlet and an outlet arranged such that the cross-sectional flow area increases from the inlet to the outlet; and

a tongue portion disposed between the collecting channel and the discharge passage and operable to separate the fluid into a first flow that flows through the collecting channel and a second flow that flows through the discharge passage, wherein the discharge portion and the tongue portion are integrally-formed as a single piece with the second housing portion.

19. The volute of claim 18 , wherein the housing includes a first housing portion and a second housing portion that cooperate to define the inlet channel and the fluid collecting channel.

20. The volute of claim 18 , wherein the tongue defines a first wall portion, a second wall portion and a central portion, and wherein the tongue is shaped such that the central portion is positioned downstream of the first wall portion and the second wall portion.

21. The volute of claim 20 , wherein the central portion is positioned to define an angle between a first radial line that passes through the first wall portion and the second wall portion, and a second radial line that passes through the central portion, wherein the angle is between about 15 degrees and 30 degrees.

22. The volute of claim 21 , wherein the angle is about 25 degrees.

23. The volute of claim 18 , wherein the fluid collecting channel has a first cross-sectional area at a first angular position and a second cross-sectional area at a second angular position, the cross-sectional area increasing substantially non-linearly between the first angular position and the second angular position.

24. A volute for use in a centrifugal compressor including a diffuser, the volute comprising:

a housing defining a central aperture, an inlet channel, and a fluid collecting channel, the housing adapted to receive the diffuser within the central aperture and to receive a discharge fluid at the inlet channel, the inlet channel directing the flow to the collecting channel;

a discharge portion coupled to the housing and including a frustoconical discharge passage in fluid communication with the collecting channel to discharge the fluid, the discharge passage having an inlet and an outlet arranged such that the cross-sectional flow area increases from the inlet to the outlet; and

a tongue portion disposed between the collecting channel and the discharge passage and operable to separate the fluid into a first flow that flows through the collecting channel and a second flow that flows through the discharge passage, wherein the tongue includes a leading edge that includes a fillet.

25. The volute of claim 24 , wherein the tongue defines a first wall portion and a second wall portion, and wherein the fillet defines a fillet size that varies between the first wall portion and the second wall portion.