Diffuser for centrifugal compressor
A discharge region of a centrifugal compressor is provided. A scroll casing is asymmetrically formed in a circumferential direction and configured to be positioned in different angular positions in the circumferential direction. A vaned diffuser is configured to be positioned in different angular positions in the circumferential direction. The vaned diffuser includes a plurality of guide elements configured to be arranged in a distributed manner in the circumferential direction. Means are provided for positioning the vaned diffuser with regard to an angular position of the asymmetrically formed scroll casing. An angular spacing of two guide elements which are arranged adjacently to each other differs from an angular spacing of two other guide elements which are arranged adjacently to each other. By varying the angular spacings between two adjacent guide vanes of a diffuser along the circumference, the resonance vibration of the compressor can be reduced.
1. A discharge region of a centrifugal compressor, comprising:
a scroll casing which is asymmetrically formed in a circumferential direction and configured to be positioned in different angular positions in the circumferential direction;
a vaned diffuser configured to be positioned in different angular positions in the circumferential direction, the vaned diffuser including a plurality of guide elements configured to be arranged in a distributed manner in the circumferential direction; and
means for positioning the vaned diffuser with regard to an angular position of the asymmetrically formed scroll casing,
wherein an angular spacing of two guide elements which are arranged adjacently to each other differs from an angular spacing of two other guide elements which are arranged adjacently to each other.
2. The discharge region of a centrifugal compressor as claimed in claim 1 , wherein a plurality of pairs of the guide elements which are arranged adjacently to each other have a different angular spacing than other guide elements among the plurality of guide elements which are arranged adjacently to each other.
3. The discharge region of a centrifugal compressor as claimed in claim 2 , wherein at least two pairs of the guide elements which are arranged adjacently to each other have a first angular spacing, and at least two other pairs of the guide elements which are arranged adjacently to each other have a second angular spacing, which is different from the first angular spacing.
4. The discharge region of a centrifugal compressor as claimed in claim 3 , wherein a plurality of the guide elements which are arranged adjacently to each other have the same angular spacing.
5. The discharge region of a centrifugal compressor as claimed in claim 4 , wherein the pairs of the guide elements with the same angular spacings are assembled from different guide elements and are arranged at a distance from each other.
6. The discharge region of a centrifugal compressor as claimed in claim 3 , wherein the pairs of the guide elements with the same angular spacings are assembled from different guide elements and are arranged at a distance from each other.
7. The discharge region of a centrifugal compressor as claimed in claim 3 , wherein the angular spacings between guide elements which are arranged adjacently to each other are distributed along the circumferential direction to follow a harmonic function.
8. The discharge region of a centrifugal compressor as claimed in claim 2 , wherein each pair of guide elements which are arranged adjacently to each other has a different angular spacing than each other pair of the guide elements which are arranged adjacently to each other.
9. The discharge region of a centrifugal compressor as claimed in claim 8 , wherein the angular spacings between guide elements which are arranged adjacently to each other are distributed along the circumferential direction to follow a harmonic function.
10. The discharge region of a centrifugal compressor as claimed in claim 2 , wherein the angular spacings between guide elements which are arranged adjacently to each other are distributed along the circumferential direction to follow a harmonic function.
11. The discharge region of a centrifugal compressor as claimed in claim 10 , wherein at least one guide element differs in at least one of length in a flow direction and shape from each other one of the guide elements.
12. The discharge region of a centrifugal compressor as claimed in claim 1 , wherein at least one guide element differs in at least one of length in a flow direction and shape from each other one of the guide elements.
13. The discharge region of a centrifugal compressor as claimed in claim 12 , wherein at least one guide element has at least one of a different inlet angle, exit angle, inlet radius and exit radius than each other one of the guide elements.
14. The discharge region of a centrifugal compressor as claimed in claim 1 , wherein at least one guide element has at least one of a different inlet angle, exit angle, inlet radius and exit radius than each other one of the guide elements.
15. An exhaust gas turbocharger comprising a centrifugal compressor with a discharge region as claimed in claim 1 .
16. The discharge region of a centrifugal compressor as claimed in claim 1 , wherein at least two pairs of the guide elements which are arranged adjacently to each other have a first angular spacing, and at least two other pairs of the guide elements which are arranged adjacently to each other have a second angular spacing, which is different from the first angular spacing.
17. The discharge region of a centrifugal compressor as claimed in claim 1 , wherein a plurality of the guide elements which are arranged adjacently to each other have the same angular spacing.
18. The discharge region of a centrifugal compressor as claimed in claim 17 , wherein the pairs of the guide elements with the same angular spacings are assembled from different guide elements and are arranged at a distance from each other.
19. The discharge region of a centrifugal compressor as claimed in claim 1 , wherein at least one guide element differs in at least one of length in a flow direction and shape from at least one of the guide elements.
20. The discharge region of a centrifugal compressor as claimed in claim 1 , wherein at least one guide element has at least one of a different inlet angle, exit angle, inlet radius and exit radius than at least one other one of the guide elements.