CENTRIFUGAL TURBO-COMPRESSOR HAVING A GAS FLOW PATH INCLUDING A RELAXATION CHAMBER

• US 20200132079A1
• Filed: 10/25/2019
• Published: 04/30/2020
• Est. Priority Date: 10/29/2018
• Status: Active Grant

• Current Assignee: Danfoss A/S
• Original Assignee: Danfoss A/S
• Inventors: Vlastuin, Jonathan, Vandesteene, Stan, Bonnefoi, Patrice
• Granted Patent: US 11,572,880 B2
• Time in Patent Office: Days
• CPC Class Codes: F04D 17/122 the individual rotor discs being, one for each stage, on a common shaft and axially spaced, e.g. conventional centrifugal multi- stage compressors
• CPC Class Codes: F04D 25/06 the pump being electrically driven F04D25/08 takes precedence
• CPC Class Codes: F04D 29/4206 especially adapted for elastic fluid pumps
• CPC Class Codes: F04D 29/4213 suction ports
• CPC Class Codes: F04D 29/441 especially adapted for elastic fluid pumps
• CPC Class Codes: F04D 29/624 especially adapted for elastic fluid pumps

Abstract

The centrifugal turbo-compressor (2) includes a hermetic casing (3); a drive shaft (6) having a longitudinal axis and rotatably arranged within the hermetic casing (3); a compression stage including an impeller (17) connected to the drive shaft (6); a gas suction inlet (42); and a gas flow path (P) fluidly connected to the gas suction inlet (42) and configured to supply the compression stage with a gas flow. The gas flow path (P) includes a relaxation chamber (46) at least partially surrounding the drive shaft (6), the gas suction inlet (42) emerging substantially radially into the relaxation chamber (46); and a plurality of inlet flow guide channels (51) fluidly connected to the relaxation chamber (46) and angularly distributed around the longitudinal axis of the drive shaft (6), the inlet flow guide channels (51) extending radially towards the drive shaft (6) and being axially offset from the gas suction inlet (42) and the relaxation chamber (46).

Claims

1. A centrifugal turbo-compressor including:

a hermetic casing,

a drive shaft having a longitudinal axis (A) and rotatably arranged within the hermetic casing,

a compression stage including an impeller connected to the drive shaft,

a gas suction inlet,

a gas flow path (P) fluidly connected to the gas suction inlet and configured to supply the compression stage with a gas flow,

wherein the gas flow path (P) includes;

a relaxation chamber at least partially surrounding the drive shaft, the gas suction inlet emerging substantially radially into the relaxation chamber, and

a plurality of inlet flow guide channels fluidly connected to the relaxation chamber and angularly distributed around the longitudinal axis (A) of the drive shaft, the inlet flow guide channels extending radially towards the drive shaft and being axially offset from the gas suction inlet and the relaxation chamber.

2. The centrifugal turbo-compressor according to claim 1, wherein the relaxation chamber extends around the drive shaft along an angular sector lower than 360°

.

3. The centrifugal turbo-compressor according to claim 2, further including a separating wall part located opposite the gas suction inlet and configured such that the relaxation chamber includes a first arcuate chamber part extending from the gas suction inlet to the separating wall part along a first angular direction with respect to the longitudinal axis (A) of the drive shaft and a second arcuate chamber part extending from the gas suction inlet to the separating wall part along a second angular direction with respect to the longitudinal axis (A) of the drive shaft which is opposite of the first angular direction.

4. The centrifugal turbo-compressor according to claim 1, wherein the relaxation chamber has a horseshoe-shaped cross sectional profile.

5. The centrifugal turbo-compressor according to claim 1, wherein an axial length (L) of the relaxation chamber is higher than an inlet diameter (D1) of the gas suction inlet.

6. The centrifugal turbo-compressor according to claim 1, wherein the gas flow path (P) further includes a connecting channel extending around the drive shaft and fluidly connecting the relaxation chamber with the inlet flow guide channels.

7. The centrifugal turbo-compressor according to claim 6, wherein the connecting channel emerges into the relaxation chamber at an outer radial portion of the relaxation chamber so as to define a flow restriction for the gas flow.

8. The centrifugal turbo-compressor according to claim 6, wherein the connecting channel is annular.

9. The centrifugal turbo-compressor according to claim 1, further including inlet flow guide members at least partially defining the inlet flow guide channels, the inlet flow guide members being angularly distributed around the longitudinal axis (A) of the drive shaft.

10. The centrifugal turbo-compressor according to claim 9, wherein each of the inlet flow guide members extends radially towards the drive shaft and converges towards the drive shaft.

11. The centrifugal turbo-compressor according to claim 1, further including an inlet distributor having an annular disc shape and surrounding the drive shaft, the inlet flow guide channels being at least partially defined by the inlet distributor.

12. The centrifugal turbo-compressor according to claim 1, wherein the gas flow path (P) further includes an annular supplying channel extending around the drive shaft and being fluidly connected to the inlet flow guide channels, the annular supplying channel being configured to axially supply the compression stage with the gas flow.

13. The centrifugal turbo-compressor according to claim 1, wherein the gas suction inlet includes a gas inlet part having a circular cross section, and a gas outlet part including a gas outlet emerging into the relaxation chamber, the gas outlet part diverging towards the relaxation chamber.

14. The centrifugal turbo-compressor according to claim 2, wherein the relaxation chamber has a horseshoe-shaped cross sectional profile.

15. The centrifugal turbo-compressor according to claim 3, wherein the relaxation chamber has a horseshoe-shaped cross sectional profile.

16. The centrifugal turbo-compressor according to claim 2, wherein an axial length (L) of the relaxation chamber is higher than an inlet diameter (D1) of the gas suction inlet.

17. The centrifugal turbo-compressor according to claim 3, wherein an axial length (L) of the relaxation chamber is higher than an inlet diameter (D1) of the gas suction inlet.

18. The centrifugal turbo-compressor according to claim 4, wherein an axial length (L) of the relaxation chamber is higher than an inlet diameter (D1) of the gas suction inlet.

19. The centrifugal turbo-compressor according to claim 2, wherein the gas flow path (P) further includes a connecting channel extending around the drive shaft and fluidly connecting the relaxation chamber with the inlet flow guide channels.

20. The centrifugal turbo-compressor according to claim 3, wherein the gas flow path (P) further includes a connecting channel extending around the drive shaft and fluidly connecting the relaxation chamber with the inlet flow guide channels.