Guide vane arrangement for use in a turbine
A guide vane arrangement for use in a turbopump having a first guide vane and a second guide vane. The second guide vane is arranged adjacent to the first guide vane such that a flow channel is defined between a leading surface of the first guide vane and a trailing surface of the second guide vane. The trailing surface of the second guide vane has a trailing portion arranged adjacent to a trailing edge of the second guide vane and which is arranged at a first angle with respect to a trailing edge of the first guide vane and the trailing edge of the second guide vane, a leading portion which is arranged adjacent to a leading edge of the second guide vane and which is arranged at a second angle with respect to the trailing edge of the first guide vane and the trailing edge of the second guide vane, and an intermediate portion arranged between the trailing portion and the leading portion and which is arranged at a third angle. The second angle is larger than each of the first and third angles.
1 . A guide vane arrangement, in particular for use in a turbo pump, which comprises:
a first guide vane, and
a second guide vane, wherein the second guide vane is arranged adjacent to the first guide vane such that a flow channel is defined between a leading surface of the first guide vane and a trailing surface of the second guide vane, wherein the flow channel is designed in such a manner that the fluid flow, when exiting the flow channel, flows at a desired first flow speed,
wherein the trailing surface of the second guide vane comprises
a trailing portion which is arranged adjacent to a trailing edge of the second guide vane and which is arranged at a first angle with respect to a virtual plane defined by a trailing edge of the first guide vane and the trailing edge of the second guide vane,
a leading portion which is arranged adjacent to a leading edge of the second guide vane and which is arranged at a second angle with respect to the virtual plane defined by the trailing edge of the first guide vane and the trailing edge of the second guide vane, and
an intermediate portion which is arranged between the trailing portion and the leading portion and which is arranged at a third angle with respect to the virtual plane defined by the trailing edge of the first guide vane and the trailing edge of the second guide vane, wherein the second angle is larger than each of the first and third angles, and
wherein the trailing surface between the intermediate portion and the trailing edge comprises at least one portion having a convex curvature.
2 . The guide vane arrangement of claim 1 ,
wherein the trailing surface of the second guide vane comprises a first transition portion between the intermediate portion and the trailing portion which defines a recompression portion of the flow channel which has a flow cross-section that decreases in the flow direction of the fluid flow flowing through the flow channel, and wherein the recompression portion is designed in such a manner that the fluid flow, upon flowing through the recompression portion, is decelerated to a second flow speed.
3 . The guide vane arrangement of claim 2 , wherein the first transition portion comprises a first concave curvature.
4 . The guide vane arrangement of claim 1 ,
wherein the trailing surface of the second guide vane comprises a second transition portion between the intermediate portion and the trailing portion which comprises a first convex curvature, wherein the second transition portion defines an additional expansion portion of the flow channel which has a flow cross-section that increases in the flow direction of the fluid flow flowing through the flow channel, and wherein the additional expansion portion is designed in such a manner that the fluid flow, upon flowing through the additional expansion portion, is accelerated to a third flow speed.
5 . The guide vane arrangement of claim 4 ,
wherein the trailing surface of the second guide vane comprises a first transition portion between the intermediate portion and the trailing portion which defines a recompression portion of the flow channel which has a flow cross-section that decreases in the flow direction of the fluid flow flowing through the flow channel, and wherein the recompression portion is designed in such a manner that the fluid flow, upon flowing through the recompression portion, is decelerated to a second flow speed, and
wherein the first transition portion is arranged between the intermediate portion and the second transition portion.
6 . The guide vane arrangement of claim 5 , wherein the third flow speed approximately corresponds to the desired first flow speed and/or is higher than the second flow speed.
7 . The guide vane arrangement of claim 5 , wherein the first transition portion comprises a first concave curvature.
8 . The guide vane arrangement of claim 1 ,
wherein the trailing portion of the trailing surface of the second guide vane comprises a second convex curvature.
9 . The guide vane arrangement of claim 8 ,
wherein the trailing surface of the second guide vane comprises a second transition portion between the intermediate portion and the trailing portion which comprises a first convex curvature, wherein the second transition portion defines an additional expansion portion of the flow channel which has a flow cross-section that increases in the flow direction of the fluid flow flowing through the flow channel, and wherein the additional expansion portion is designed in such a manner that the fluid flow, upon flowing through the additional expansion portion, is accelerated to a third flow speed, and
wherein the trailing portion of the trailing surface of the second guide vane comprises a second concave curvature between the first and second convex curvatures.
10 . The guide vane arrangement of claim 1 ,
wherein the leading portion of the second guide vane has a leading portion curvature with an inflection point where a concave curvature of a concave-shaped portion passes over in a convex curvature of a convex-shaped portion, and wherein the concave-shaped portion is provided upstream of the convex-shaped portion.
11 . The guide vane arrangement of claim 1 ,
wherein the trailing surface of the second guide vane comprises a third transition portion between the leading portion and the intermediate portion, wherein the third transition portion comprises a third convex curvature, and wherein the third transition portion and the outlet portion of the leading surface of the first guide vane define an expansion portion of the flow channel which has a flow cross-section that increases in the flow direction of the fluid flow flowing through the flow channel, and wherein the expansion portion is designed in such a manner that the fluid flow, upon flowing through the expansion portion, is accelerated to a fourth flow speed.
12 . The guide vane arrangement of claim 1 ,
wherein the third angle of the intermediate portion is smaller than the first angle of the trailing portion.
13 . The guide vane arrangement of claim 1 ,
wherein the leading surface of the first guide vane comprises at least one of:
an inlet portion which is arranged adjacent to a leading edge of the first guide vane and which, with respect to the flow channel, is arranged opposite to the leading portion of the trailing surface of the second guide vane, wherein the inlet portion of the leading surface of the first guide vane and the leading portion of the trailing surface of the second guide vane define a restricting portion of the flow channel which has a flow cross-section that decreases in a flow direction of the fluid flow flowing through the flow channel, and
an outlet portion which is arranged adjacent to a trailing edge of the first guide vane, wherein a projection of the leading portion of the trailing surface of the second guide vane into the virtual plane at least partially coincides with a projection of the outlet portion of the leading surface of the first guide vane into the virtual plane.
14 . The guide vane arrangement of claim 13 ,
wherein a projection of the intermediate portion and/or of the first transition portion and/or of second transition portion and/or of the trailing portion of the trailing surface of the second guide vane into the virtual plane does not coincide with the projection of outlet portion of the leading surface of the first guide vane into the virtual plane.
15 . A turbine, in particular for use in a turbo pump, comprising the guide vane arrangement of claim 1 .
16 . A method of operating a guide vane arrangement, comprising:
supplying a fluid flow to a flow channel defined between a leading surface of a first guide vane and a trailing surface of a second guide vane, and
guiding the fluid flow along a trailing portion of the trailing surface of the second guide vane which is arranged adjacent to a trailing edge of the second guide vane and thereby deflecting the fluid flow such that the fluid flow exits the flow channel at a first flow angle with respect to a virtual plane defined by a trailing edge of the first guide vane and the trailing edge of the second guide vane and with a desired first flow speed,
wherein the fluid flow, prior to being guided along the trailing portion of the trailing surface, is guided along a leading portion of the trailing surface of the second guide vane which is arranged adjacent to a leading edge of the second guide vane and thereby deflected such that the fluid flow flows at a second flow angle with respect to the virtual plane defined by the trailing edge of the first guide vane and the trailing edge of the second guide vane, and thereafter is guided
along an intermediate portion of the trailing surface of the second guide vane which is arranged between the trailing portion and the leading portion and thereby deflected such that the fluid flow flows at a third flow angle with respect to the virtual plane defined by the trailing edge of the first guide vane and the trailing edge of the second guide vane, wherein the second flow angle is larger than each of the third flow angle and the first flow angle, and thereafter is guided
along a first transition portion of the trailing surface of the second guide vane which is arranged between the intermediate portion and the trailing portion and which defines a recompression portion of the flow channel which has a flow cross-section that decreases in the flow direction of the fluid flow flowing through the flow channel, and wherein the recompression portion is designed in such a manner that the fluid flow, upon flowing through the recompression portion, is decelerated to a second flow speed, and thereafter is guided
along a second transition portion of the trailing surface of the second guide vane which is arranged between the first transition portion and the trailing portion and which defines an additional expansion portion of the flow channel which has a flow cross-section that increases in the flow direction of the fluid flow flowing through the flow channel, and wherein the additional expansion portion is designed in such a manner that the fluid flow, upon flowing through the expansion portion, is accelerated to a third flow speed.
17 . The method of claim 16 ,
wherein the fluid flow, prior to being guided along the trailing portion of the trailing surface, is guided
along a third transition portion of the trailing surface of the second guide vane which is arranged between the leading portion and the intermediate portion, wherein the third transition portion and an outlet portion of the leading surface of the first guide vane define an expansion portion of the flow channel which has a flow cross-section that increases in the flow direction of the fluid flow flowing through the flow channel, and wherein the expansion portion is designed in such a manner that the fluid flow, upon flowing through the expansion portion, is accelerated to a fourth flow speed.
18 . The method of claim 17 , wherein the fourth flow speed is higher than the desired first flow speed.
19 . The method of claim 16 ,
comprising at least one of the following:
the first transition portion of the trailing surface of the second guide vane comprises a first concave curvature,
the second transition portion of the trailing surface of the second guide vane comprises a first convex curvature,
the trailing portion of the trailing surface of the second guide vane comprises a second convex curvature,
the third transition portion of the trailing surface of the second guide vane comprises a third convex curvature,
the trailing portion of the trailing surface of the second guide vane comprises a second concave curvature between the first and second convex curvatures, and
the leading portion comprises a leading portion curvature with an inflection point where a concave curvature of a concave-shaped portion passes over in a convex curvature of a convex-shaped portion, wherein the concave-shaped portion is provided upstream the convex-shaped portion.
20 . The method of claim 16 , wherein the third flow speed approximately corresponds to the desired first flow speed.