CA2436670C - Hydraulic turbine with interblade vortex suppressor - Google Patents
Hydraulic turbine with interblade vortex suppressor Download PDFInfo
- Publication number
- CA2436670C CA2436670C CA2436670A CA2436670A CA2436670C CA 2436670 C CA2436670 C CA 2436670C CA 2436670 A CA2436670 A CA 2436670A CA 2436670 A CA2436670 A CA 2436670A CA 2436670 C CA2436670 C CA 2436670C
- Authority
- CA
- Canada
- Prior art keywords
- blade
- blades
- turbine runner
- fin
- crown
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 30
- 230000002411 adverse Effects 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- RLQJEEJISHYWON-UHFFFAOYSA-N flonicamid Chemical compound FC(F)(F)C1=CC=NC=C1C(=O)NCC#N RLQJEEJISHYWON-UHFFFAOYSA-N 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03B—MACHINES OR ENGINES FOR LIQUIDS
- F03B3/00—Machines or engines of reaction type; Parts or details peculiar thereto
- F03B3/12—Blades; Blade-carrying rotors
- F03B3/125—Rotors for radial flow at high-pressure side and axial flow at low-pressure side, e.g. for Francis-type turbines
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03B—MACHINES OR ENGINES FOR LIQUIDS
- F03B11/00—Parts or details not provided for in, or of interest apart from, the preceding groups, e.g. wear-protection couplings, between turbine and generator
- F03B11/04—Parts or details not provided for in, or of interest apart from, the preceding groups, e.g. wear-protection couplings, between turbine and generator for diminishing cavitation or vibration, e.g. balancing
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/20—Hydro energy
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Hydraulic Turbines (AREA)
Abstract
An improved Francis-type turbine runner. To extend operating range to partial load, inter blade fins partially extend into the flow paths between the runner blades. The inter blade fins correspond in shape and pattern with the shape and pattern of that portion of the runner blades with which the fins coextend along the flow paths between blades. The fins are recessed rearwardly of the flow dividing edges of the runner blades in the flow paths between the runner blades and reduce occurrence of inter blade vortices during partial or low load operating conditions. The shape of the interblade fins is further improved by tilting or sloping the tip of the interblade fin towards the suction surface of the adjacent blade. This creates a small convergence in the flow path between the fin and the suction surface of the blade.
Description
HYDRAULIC TURBINE WITH INTERBLADE VORTEX SUPPRESSOR
Field of the Invention The present invention relates to a hydraulic turbine and, in particular, to a Francis turbine having a rotary runner with inter blade fins spaced between the runner blades to suppress inter blade vortices.
BACKGROUND OF THE INVENTION
Hydroelectric turbines have blade shapes chosen to optimize turbine performance over a range of operating conditions. Typically the turbine is designed with the vanes or blades of the runner formed with identical shapes and equally spaced apart.
Recently, utility operators have requested to extend further the range of operating conditions to partial or low load conditions. However, operating the turbine at partial load has resulted in inter blade vortices occurring in the water flowing past the blades. These inter blade vortices appear between the blades recessed partway back from the leading edge of the blades and are attached to the crown of the turbine runner. The vortices extend though the water flow path towards the discharge end of the runner. These inter blade vortices may be responsible for damage to crowns surfaces.
The reduction of wasteful disturbances between vanes is addressed by US Patent 1,836,860 issued December 15, 1931 to L.F. Moody. Moody (~ECAN3241 _2_ discloses many different blade configurations and in one embodiment discloses the use of two intermediate blades of differing size positioned toward the low pressure or suction face of a main runner blade. The intermediate blades break up the water flow channel on the suction face of the blade into smaller channels. The intermediate blades are positioned closer to the suction face of one adjacent main blade than the pressure face of the other adjacent main blade and the intermediate blades extend all the way from the crown to the bend of the runner. This may be disadvantageous to the efficiency of the turbine operating at normal load conditions. Further the relative shape and orientation of the intermediate blades and the main blade are not discussed by Moody.
Accordingly, there is a need to develop a turbine for present day hydroelectric facilities that operates efficiently under norrrial load conditions and that is not subject to developing inter blade vortices at low or partial load conditions.
Summary of The Invention The present invention relates to an improved Francis-type turbine runner that has a significant reduction in inter blade vortices. The turbine runner has inter blade fins partially extending in the flow path between the runner blades. The inter blade fins correspond In shape and pattern with the shape and pattern of that portion of the runner blades with which the fins coextend along the flow paths between the blades.
The inter blade vns provide the advantage that any cavitating vortex that normally attach to the crown in the region o~f the inlet under either low or partial load operation are prevented from occurring or suppressed by the inter blade fins. Further, the use of the inter blade fins have little adverse effect on the efficiency of the turbine while operating at normal or rated conditions.
The shape of the interblade fins is further improved by tilting or sloping the tip of the interblade fin towards the suction surface of the adjacent blade.
This creates a small convergence in the flow path between the fin and the suction surface of the blade. This convergence improves the ability of the fins to counteract the formatiori of interblade votices during partial load conditions.
The inter blade fins are suspended from the crown of the turbine and extend partially into the flow paths of each of the blades. At least one inter blade fin is positioned between each pair of adjacent blades. The fins coextend along the flow path between a pressure surface portion of the pressure face of one adjacent blade and a suction surface portion of suction face of another adjacent blade.
in an embodiment where one fin is positioned between each adjacent blade, the intersection between fin and crown is located equally positioned from each adjacent blade. That is the fin is located towards the center or in the center of the flow path between the adjacent blades. When more than one fin is utilized between adjacent blades, these fins are spaced equi-distance from each other and also from the adjacent blades at the intersection of the fin with the crown. It should be understood that the fins do not divide the flow path channels between the blades into separate channels but instead only partially extend into the flow paths from the crown to counteract the develop of inter blade vortices without a significant reduction in turbine performance at normal load conditions.
The inter blade fin in one embodiment has a leading edge portion that is positioned rearwardly of the flow dividing edges of the adjacent blades.
The inter blade fin shape is chosen to have a fin suction surface whose pattern corresponds in shape to the suction surface portions of the adjacent blades and the fin also a fin pressure surface portion whose pattern corresponds in shape to the pressure surface portions of adjacent blades:
Accordingly, the fin initial geometry, subject to optimization, corresponds in shape and pattern along the flow path with the shape and pattern of that surface portion of the corresponding adjacent blades.
In one embodiment, each of the blade fins is located in the flow path between each of the blades and about one third of the distance along the flow path from the water inlet of the blade. Further, each of the blade fins extends from the crown into the flow path for about one third of the distance to the water outlet end.
_4_ In accordance with the present invention, there is provided a Francis-type hydraulic turbine runner rotatable about an axis of rotation. The turbine runner comprises a crown forming an upper axial end thereof when the axis of rotation is substantially vertical. The turbine runner has a band concentric with the crown on the axis of rotation. The band and the crown form a water inlet. The runner terminates at its lower end in a water outlet. The turbine runner has an array of blades extending between the band and the crown.
Each of the blades in the array has a suction face and a pressure face trailing the suction face in the direction of rotation defining flow paths between adjacent blades in the array that extend from the water inlet end to the water outlet end. The turbine runner compries a plurality of inter blade fins suspended from the crown of the turbine runner and extending partially into the flow paths between each of the blades wherein at least one inter blade fin is positioned between each pair of adjacent blades in the array of blades and coextends along the flow path with a pressure surface portion of the pressure face of a first blade of the pair of blades and with a suction surtace portion of the suction face of a second blade of the pair of adjacent blades.
Brief Description of The Drawings For a better understanding of the nature and objects of the present invention reference may be had to the accompanying diagrammatic drawings in which:
FIG. 1 is an illustration of a conventional Francis-type turbine showing a typical shape and orientation of the blades;
FIG. 2 is a Francis turbine constructed showing a revised orientation and curvature of the blades and showing the placement of the inter blade vortex suppressor tins of the present invention;
FIG. 3 is a front view looking radially inward of the turbine of a first embodiment of an isolated runner blade and an adjacent vortex suppressing inter blade fin of the present invention;
FIG. 4 is a side view of the fin and blade shown in FIG 3;
_5_ FIG. 5 is a axial view of the turbine looking in a direction from the crown toward the outlet end of the blade and fin of FIG. 1;
FIG. 6 is a front view looking radially inward of the turbine of a second embodiment of an isolated runner blade and an adjacent vortex suppressing inter blade fin of the present invention;
FIG. 7 is a side view of the fin and blade shown in FIG 6;
FIG. 8 is a axial view of the turbine looking in a direction from the crown toward the outlet end of the blade and fin of FIG. 6;
FIG. 9 is a front view looking radially inward of the turbine of a first embodiment of an isolated runner blade and an adjacent vortex suppressing inter blade fin of the present invention;.
FIG. 10 is a side view of the fin and blade shown in FIG 9; and, FIG. 11 is a axial view of the turbine looking i~~ a direction from the crown toward the outlet end of the blade and fin of FIG 9.
Description Of The Invention The present invention relates to a hydraulic turbine and, in particular, to a Francis turbine having a rotary runner with inter blade fins spaced between the runner blades to suppress inter blade vortices.
FIG. 1 shows a prior art Francis runner 10, having a crown 12 with a conventionally shaped substantially conical hub (not shown) and forming one axial end 15 thereof, a band or ring 14 concentric with the crown on the axis of rotation of the runner and a plurality of blades 16 interposed between the crown 12 and band or ring 14. Flow paths generally indicated at 18 permit water to enter the runner in a substantially radial direction at water inlet and pass smoothly through the runner to the outlet end 40 at the end of the runner 10 in FIG. 1 axially remote from the crown 12. These flow paths 18 are formed between pairs of adjacent blades 16. The outer peripheral edges 20 of the blades 16 between the band 14 and crowri 12 are defined by the _0_ junction of the suction face 22 leading in the direcaion of rotation of the runner and pressure faces 24 itrailing in the direction c~f rotation when operated in the turbine mode) of the blades 16 define the flovu dividing edges 20 directing the water into adjacent flow paths on opposite :aides of each of the blades.
These flow dividing edges 20 are not sharp edges but are smoothly contoured to facilitate water flow along opposite faces of the blade:.
It will be noted in the prior art that each of these edges 20, and in fact the whole of each blade 16, extending up from the water outlet end 40 towards the crown 12, is sloped forwardly in the direction in which the runner is rotated by water flow through the passages 18. This direction is indicated by the arrow 2Ei.
FIG 2. shows a I=rancis-type turbine runner 10U having a crown 120 and forming one axial end 125 of the runner, a band or ring 140 concentric therewith on the axis of o-otation of the runner and an array of blades 160.
The blades 160 have flow paths 130 formed between the blades 160 leading from the substantially radial inlet adjacent the outer peiriphery of the blades and the outlet end 190 and through which the water flows as the runner 100 rotates on its axis in the direction indicated by arrow 200.
The flow dividing edges 220 formed at the outer periphery of the blades 160 between band or ring 140 and crown 120 define the line of junction between the suction and pressure faces 222 and 224 respectively of the blades for direction of rotation 200. In the FIG. 2 embodiment, at least a portion the flow dividing edges 220 and of portion of the body of each blade extending toward the crown 120 are sloped rearwardly in the direction of rotation. The blades 100 can be curved to havE: an X shaped configuration when viewing the blade 160 radially inward of the turbine runner 100 from the flow dividing edge 220.
Spaced between the blades 160 suspencled from the crown 120 are the inter blade vortex suppressor fins 300 of the present invention. It should be understood that between each blade 160 is located', one fin 300. The fin 300 is spaced between the blades 160 by squall distances or displacement.
_7_ In an alternative embodiment where two or more fins are positioned between the blades 160, then the fins are positioned apart from each other by the same spacing between each blade and adjacent fin 300.
Referring now to FIGs. 3, 4 and 5 there i~> shown a front view, a side view and top view respectively of one blade configuration 160. In this blade configuration 160, there is shown positioned adj<~cent to the suction surface 222 the inter blade fin 300. The shape of the inter blade fin 300 is shown to correspond to the shape of the blade 160. The fin 300 has suction surface 322 which corresponds in shape to a suction surface portion of the suction surface 222 that overlaps with the inter blade fin 300. The fin 300 has pressure surface 324 which corresponds in shape to a pressure surface portion of the pressure surface 224 that overlaps with the inter blade fin 300.
In this manner the inter blade fin 300 overlaps or c~extends in the direction of water flow through or between the blades 160 with adjacent the adjacent suction surface portion and the adjacent the pressure surface portion of adjacent blades 160. As shown in Figure 4, the leading edge 320 of the inter blade fin 300 is recessed rearwardly of the leading edge 220 of the blade 160. Further, the fin 300 extends downwardly from the crown into the flow path as shown in Figure 4 to extend to downward edge 325.
Alternative embodiments of blade configurations and correspondingly configured inter blade firs are shown for Figure;> 6, 7 and 8 as well as the blade shown for Figures 9, 10 and 11. The same reference numbers as used above for Figures 3, 4 and 5 are used in Figures 6 to 11.
The inter blade fin 300 may also be provided v~rith a tip portion 340.
The tip is relatively pronounced and is best shown in Figures 9 and 10. In Figures 3 and 9, the tip portion 340 of the interblade fin 300 is shown tilted towards the suction surface 222 of the adjacent blade 160 to converge the flow path 180 between the inter blade fin 300 and the suction surface 222 of the blade 180.
In the embodiments illustrated, the inter blade fi'n 300 starts with the flow path about one third back from the flow dividiing edges 220 of the blades C~ ECA~13241 _g_ 160. Further, the fin 300 extends downwardly from the crown 120 about one third of the distance towards the water outlet end 140.
While the invention has been described in connection with what is presently considered to be practical embodiments, it is to be understood that the invention is not to be limited therto, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
Field of the Invention The present invention relates to a hydraulic turbine and, in particular, to a Francis turbine having a rotary runner with inter blade fins spaced between the runner blades to suppress inter blade vortices.
BACKGROUND OF THE INVENTION
Hydroelectric turbines have blade shapes chosen to optimize turbine performance over a range of operating conditions. Typically the turbine is designed with the vanes or blades of the runner formed with identical shapes and equally spaced apart.
Recently, utility operators have requested to extend further the range of operating conditions to partial or low load conditions. However, operating the turbine at partial load has resulted in inter blade vortices occurring in the water flowing past the blades. These inter blade vortices appear between the blades recessed partway back from the leading edge of the blades and are attached to the crown of the turbine runner. The vortices extend though the water flow path towards the discharge end of the runner. These inter blade vortices may be responsible for damage to crowns surfaces.
The reduction of wasteful disturbances between vanes is addressed by US Patent 1,836,860 issued December 15, 1931 to L.F. Moody. Moody (~ECAN3241 _2_ discloses many different blade configurations and in one embodiment discloses the use of two intermediate blades of differing size positioned toward the low pressure or suction face of a main runner blade. The intermediate blades break up the water flow channel on the suction face of the blade into smaller channels. The intermediate blades are positioned closer to the suction face of one adjacent main blade than the pressure face of the other adjacent main blade and the intermediate blades extend all the way from the crown to the bend of the runner. This may be disadvantageous to the efficiency of the turbine operating at normal load conditions. Further the relative shape and orientation of the intermediate blades and the main blade are not discussed by Moody.
Accordingly, there is a need to develop a turbine for present day hydroelectric facilities that operates efficiently under norrrial load conditions and that is not subject to developing inter blade vortices at low or partial load conditions.
Summary of The Invention The present invention relates to an improved Francis-type turbine runner that has a significant reduction in inter blade vortices. The turbine runner has inter blade fins partially extending in the flow path between the runner blades. The inter blade fins correspond In shape and pattern with the shape and pattern of that portion of the runner blades with which the fins coextend along the flow paths between the blades.
The inter blade vns provide the advantage that any cavitating vortex that normally attach to the crown in the region o~f the inlet under either low or partial load operation are prevented from occurring or suppressed by the inter blade fins. Further, the use of the inter blade fins have little adverse effect on the efficiency of the turbine while operating at normal or rated conditions.
The shape of the interblade fins is further improved by tilting or sloping the tip of the interblade fin towards the suction surface of the adjacent blade.
This creates a small convergence in the flow path between the fin and the suction surface of the blade. This convergence improves the ability of the fins to counteract the formatiori of interblade votices during partial load conditions.
The inter blade fins are suspended from the crown of the turbine and extend partially into the flow paths of each of the blades. At least one inter blade fin is positioned between each pair of adjacent blades. The fins coextend along the flow path between a pressure surface portion of the pressure face of one adjacent blade and a suction surface portion of suction face of another adjacent blade.
in an embodiment where one fin is positioned between each adjacent blade, the intersection between fin and crown is located equally positioned from each adjacent blade. That is the fin is located towards the center or in the center of the flow path between the adjacent blades. When more than one fin is utilized between adjacent blades, these fins are spaced equi-distance from each other and also from the adjacent blades at the intersection of the fin with the crown. It should be understood that the fins do not divide the flow path channels between the blades into separate channels but instead only partially extend into the flow paths from the crown to counteract the develop of inter blade vortices without a significant reduction in turbine performance at normal load conditions.
The inter blade fin in one embodiment has a leading edge portion that is positioned rearwardly of the flow dividing edges of the adjacent blades.
The inter blade fin shape is chosen to have a fin suction surface whose pattern corresponds in shape to the suction surface portions of the adjacent blades and the fin also a fin pressure surface portion whose pattern corresponds in shape to the pressure surface portions of adjacent blades:
Accordingly, the fin initial geometry, subject to optimization, corresponds in shape and pattern along the flow path with the shape and pattern of that surface portion of the corresponding adjacent blades.
In one embodiment, each of the blade fins is located in the flow path between each of the blades and about one third of the distance along the flow path from the water inlet of the blade. Further, each of the blade fins extends from the crown into the flow path for about one third of the distance to the water outlet end.
_4_ In accordance with the present invention, there is provided a Francis-type hydraulic turbine runner rotatable about an axis of rotation. The turbine runner comprises a crown forming an upper axial end thereof when the axis of rotation is substantially vertical. The turbine runner has a band concentric with the crown on the axis of rotation. The band and the crown form a water inlet. The runner terminates at its lower end in a water outlet. The turbine runner has an array of blades extending between the band and the crown.
Each of the blades in the array has a suction face and a pressure face trailing the suction face in the direction of rotation defining flow paths between adjacent blades in the array that extend from the water inlet end to the water outlet end. The turbine runner compries a plurality of inter blade fins suspended from the crown of the turbine runner and extending partially into the flow paths between each of the blades wherein at least one inter blade fin is positioned between each pair of adjacent blades in the array of blades and coextends along the flow path with a pressure surface portion of the pressure face of a first blade of the pair of blades and with a suction surtace portion of the suction face of a second blade of the pair of adjacent blades.
Brief Description of The Drawings For a better understanding of the nature and objects of the present invention reference may be had to the accompanying diagrammatic drawings in which:
FIG. 1 is an illustration of a conventional Francis-type turbine showing a typical shape and orientation of the blades;
FIG. 2 is a Francis turbine constructed showing a revised orientation and curvature of the blades and showing the placement of the inter blade vortex suppressor tins of the present invention;
FIG. 3 is a front view looking radially inward of the turbine of a first embodiment of an isolated runner blade and an adjacent vortex suppressing inter blade fin of the present invention;
FIG. 4 is a side view of the fin and blade shown in FIG 3;
_5_ FIG. 5 is a axial view of the turbine looking in a direction from the crown toward the outlet end of the blade and fin of FIG. 1;
FIG. 6 is a front view looking radially inward of the turbine of a second embodiment of an isolated runner blade and an adjacent vortex suppressing inter blade fin of the present invention;
FIG. 7 is a side view of the fin and blade shown in FIG 6;
FIG. 8 is a axial view of the turbine looking in a direction from the crown toward the outlet end of the blade and fin of FIG. 6;
FIG. 9 is a front view looking radially inward of the turbine of a first embodiment of an isolated runner blade and an adjacent vortex suppressing inter blade fin of the present invention;.
FIG. 10 is a side view of the fin and blade shown in FIG 9; and, FIG. 11 is a axial view of the turbine looking i~~ a direction from the crown toward the outlet end of the blade and fin of FIG 9.
Description Of The Invention The present invention relates to a hydraulic turbine and, in particular, to a Francis turbine having a rotary runner with inter blade fins spaced between the runner blades to suppress inter blade vortices.
FIG. 1 shows a prior art Francis runner 10, having a crown 12 with a conventionally shaped substantially conical hub (not shown) and forming one axial end 15 thereof, a band or ring 14 concentric with the crown on the axis of rotation of the runner and a plurality of blades 16 interposed between the crown 12 and band or ring 14. Flow paths generally indicated at 18 permit water to enter the runner in a substantially radial direction at water inlet and pass smoothly through the runner to the outlet end 40 at the end of the runner 10 in FIG. 1 axially remote from the crown 12. These flow paths 18 are formed between pairs of adjacent blades 16. The outer peripheral edges 20 of the blades 16 between the band 14 and crowri 12 are defined by the _0_ junction of the suction face 22 leading in the direcaion of rotation of the runner and pressure faces 24 itrailing in the direction c~f rotation when operated in the turbine mode) of the blades 16 define the flovu dividing edges 20 directing the water into adjacent flow paths on opposite :aides of each of the blades.
These flow dividing edges 20 are not sharp edges but are smoothly contoured to facilitate water flow along opposite faces of the blade:.
It will be noted in the prior art that each of these edges 20, and in fact the whole of each blade 16, extending up from the water outlet end 40 towards the crown 12, is sloped forwardly in the direction in which the runner is rotated by water flow through the passages 18. This direction is indicated by the arrow 2Ei.
FIG 2. shows a I=rancis-type turbine runner 10U having a crown 120 and forming one axial end 125 of the runner, a band or ring 140 concentric therewith on the axis of o-otation of the runner and an array of blades 160.
The blades 160 have flow paths 130 formed between the blades 160 leading from the substantially radial inlet adjacent the outer peiriphery of the blades and the outlet end 190 and through which the water flows as the runner 100 rotates on its axis in the direction indicated by arrow 200.
The flow dividing edges 220 formed at the outer periphery of the blades 160 between band or ring 140 and crown 120 define the line of junction between the suction and pressure faces 222 and 224 respectively of the blades for direction of rotation 200. In the FIG. 2 embodiment, at least a portion the flow dividing edges 220 and of portion of the body of each blade extending toward the crown 120 are sloped rearwardly in the direction of rotation. The blades 100 can be curved to havE: an X shaped configuration when viewing the blade 160 radially inward of the turbine runner 100 from the flow dividing edge 220.
Spaced between the blades 160 suspencled from the crown 120 are the inter blade vortex suppressor fins 300 of the present invention. It should be understood that between each blade 160 is located', one fin 300. The fin 300 is spaced between the blades 160 by squall distances or displacement.
_7_ In an alternative embodiment where two or more fins are positioned between the blades 160, then the fins are positioned apart from each other by the same spacing between each blade and adjacent fin 300.
Referring now to FIGs. 3, 4 and 5 there i~> shown a front view, a side view and top view respectively of one blade configuration 160. In this blade configuration 160, there is shown positioned adj<~cent to the suction surface 222 the inter blade fin 300. The shape of the inter blade fin 300 is shown to correspond to the shape of the blade 160. The fin 300 has suction surface 322 which corresponds in shape to a suction surface portion of the suction surface 222 that overlaps with the inter blade fin 300. The fin 300 has pressure surface 324 which corresponds in shape to a pressure surface portion of the pressure surface 224 that overlaps with the inter blade fin 300.
In this manner the inter blade fin 300 overlaps or c~extends in the direction of water flow through or between the blades 160 with adjacent the adjacent suction surface portion and the adjacent the pressure surface portion of adjacent blades 160. As shown in Figure 4, the leading edge 320 of the inter blade fin 300 is recessed rearwardly of the leading edge 220 of the blade 160. Further, the fin 300 extends downwardly from the crown into the flow path as shown in Figure 4 to extend to downward edge 325.
Alternative embodiments of blade configurations and correspondingly configured inter blade firs are shown for Figure;> 6, 7 and 8 as well as the blade shown for Figures 9, 10 and 11. The same reference numbers as used above for Figures 3, 4 and 5 are used in Figures 6 to 11.
The inter blade fin 300 may also be provided v~rith a tip portion 340.
The tip is relatively pronounced and is best shown in Figures 9 and 10. In Figures 3 and 9, the tip portion 340 of the interblade fin 300 is shown tilted towards the suction surface 222 of the adjacent blade 160 to converge the flow path 180 between the inter blade fin 300 and the suction surface 222 of the blade 180.
In the embodiments illustrated, the inter blade fi'n 300 starts with the flow path about one third back from the flow dividiing edges 220 of the blades C~ ECA~13241 _g_ 160. Further, the fin 300 extends downwardly from the crown 120 about one third of the distance towards the water outlet end 140.
While the invention has been described in connection with what is presently considered to be practical embodiments, it is to be understood that the invention is not to be limited therto, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
Claims (16)
1. A Francis-type hydraulic turbine runner rotatable about an axis of rotation, said turbine runner comprising:
a crown forming the upper axial end thereof when the axis of rotation is substantially vertical;
a band concentric with the crown on the axis of rotation, the band and crown forming a water inlet end and the runner terminating at its lower end in a water outlet end;
an array of blades extending between the band and the crown, each of the blades in the array having a suction face and a pressure face trailing the suction face in the direction of rotation defining flow paths between adjacent blades in the array that extend from the water inlet end to the water outlet end; and, a plurality of inter blade fins suspended from the crown of the turbine runner and extending partially into the flow paths between each of the blades wherein at least one inter blade fin is positioned between each pair of adjacent blades in the array of blades and coextends along the flow path with a pressure surface portion of the pressure face of a first blade of the pair of blades and with a suction surface portion of the suction face of a second blade of the pair of adjacent blades.
a crown forming the upper axial end thereof when the axis of rotation is substantially vertical;
a band concentric with the crown on the axis of rotation, the band and crown forming a water inlet end and the runner terminating at its lower end in a water outlet end;
an array of blades extending between the band and the crown, each of the blades in the array having a suction face and a pressure face trailing the suction face in the direction of rotation defining flow paths between adjacent blades in the array that extend from the water inlet end to the water outlet end; and, a plurality of inter blade fins suspended from the crown of the turbine runner and extending partially into the flow paths between each of the blades wherein at least one inter blade fin is positioned between each pair of adjacent blades in the array of blades and coextends along the flow path with a pressure surface portion of the pressure face of a first blade of the pair of blades and with a suction surface portion of the suction face of a second blade of the pair of adjacent blades.
2. The turbine runner of claim 1 wherein the interblade fins is has a tip portion tilted towards the suction surface of the second blade to converge the flow path between the inter blade fin and the suction surface of the second blade.
3. The turbine runner of claim 1 wherein the at least one inter blade fin is positioned equi-distant from the first and second blade of the pair of adjacent blades along the crown of the runner.
4. The turbine runner of claim 1 wherein the suction and pressure faces of each blade of the array of blades meets between the band and the crown at an outer periphery defining a flow dividing edge and wherein the at least one inter blade fin has a leading edge positioned in the flow path rearwardly of the flow dividing edges of the first and second blades of the pair of adjacent blades.
5. The turbine runner of claim 1 wherein the at least one inter blade fin has a fin suction surface whose pattern corresponds in shape to the suction surface portion of the second blade and has a fin pressure surface portion whose pattern corresponds in shape to the pressure surface portion of the first blade.
6. The turbine runner of claim 1 wherein each blade in the array of blades has an x shaped configuration when viewing the blade radially inward of the turbine runner from the flow dividing edge of each blade, and the inter blade fins between the array of blades each has a shape and pattern similar to the shape and pattern of the array of blades for that portion of the array of blades that the inter blade fins coextend with through the flow paths.
7. The turbine runner of claim 1 wherein each of the blade fins is located in the flow path between each of the blades about one third of the distance along the flow path from the water inlet end of the turbine runner.
8. The turbine runner of claim 4 wherein each of the blade fins extends from the crown into the flow path for about one third of the distance to the water outlet end.
9. A Francis-type hydraulic turbine runner rotatable about an axis of rotation, said turbine runner comprising:
a crown forming the upper axial end thereof when the axis of rotation is substantially vertical;
a band concentric with the crown on the axis of rotation, the band and crown forming a water inlet end and the runner terminating at its lower end in a water outlet end;
an array of blades extending between the band and the crown, each of the blades in the array having a suction face and a pressure face trailing the suction face in the direction of rotation, the suction and pressure faces meeting between the band and the crown at an outer periphery defining a flow dividing edge for each of the blades, the suction and pressure faces providing substantially smooth streamlined surface to define flow paths between adjacent blades in the array that extend from the water inlet end to the water outlet end; and, a plurality of inter blade fins suspended from the crown of the turbine runner and extending partially into the flow paths between each of the blades for suppressing interblade vortices wherein at least one inter blade fin is positioned between each pair of adjacent blades in the array of blades and coextends along the flow path with a pressure surface portion of the pressure face of a first blade of the pair of blades and with a suction surface portion of the suction face of a second blade of the pair of adjacent blades.
a crown forming the upper axial end thereof when the axis of rotation is substantially vertical;
a band concentric with the crown on the axis of rotation, the band and crown forming a water inlet end and the runner terminating at its lower end in a water outlet end;
an array of blades extending between the band and the crown, each of the blades in the array having a suction face and a pressure face trailing the suction face in the direction of rotation, the suction and pressure faces meeting between the band and the crown at an outer periphery defining a flow dividing edge for each of the blades, the suction and pressure faces providing substantially smooth streamlined surface to define flow paths between adjacent blades in the array that extend from the water inlet end to the water outlet end; and, a plurality of inter blade fins suspended from the crown of the turbine runner and extending partially into the flow paths between each of the blades for suppressing interblade vortices wherein at least one inter blade fin is positioned between each pair of adjacent blades in the array of blades and coextends along the flow path with a pressure surface portion of the pressure face of a first blade of the pair of blades and with a suction surface portion of the suction face of a second blade of the pair of adjacent blades.
10. The turbine runner of claim 9 wherein the interblade fins is has a tip portion tilted towards the suction surface of tile second blade to converge the flow path between the inter blade fin and the suction surface of the second blade.
11. The turbine runner of claim 9 wherein the at least one inter blade fin is positioned equi-distant from the first and second blade of the pair of adjacent blades along the crown of the runner.
12. The turbine runner of claim 11 wherein the at least one inter blade fin has a leading edge positioned in the flow path rearwardly of the flow dividing edges of the first and second blades of the pair of adjacent blades.
13. The turbine runner of claim 12 wherein the at least one inter blade fin has a fin suction surface whose pattern corresponds in shape to the suction surface portion of the second blade and has a fin pressure surface portion whose pattern corresponds in shape to the pressure surface portion of the first blade.
14. The turbine runner of claim 9 wherein each blade in the array of blades has an x shaped configuration when viewing the blade radially inward of the turbine runner from the flow dividing edge of each blade, and the inter blade fins between the array of blades each has a shape and pattern similar to the shape and pattern of the array of blades for that portion of the array of blades that the inter blade fins coextend with through the flow paths.
15. The turbine runner of claim 9 wherein each of the blade fins is located in the flow path between each of the blades about one third of the distance along the flow path from the water inlet end of the turbine runner.
16. The turbine runner of claim 12 wherein each of the blade fins extends from the crown into the flow path for about one third of the distance to the water outlet end.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA2436670A CA2436670C (en) | 2003-08-07 | 2003-08-07 | Hydraulic turbine with interblade vortex suppressor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA2436670A CA2436670C (en) | 2003-08-07 | 2003-08-07 | Hydraulic turbine with interblade vortex suppressor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2436670A1 CA2436670A1 (en) | 2005-02-07 |
| CA2436670C true CA2436670C (en) | 2011-05-10 |
Family
ID=34120694
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2436670A Expired - Fee Related CA2436670C (en) | 2003-08-07 | 2003-08-07 | Hydraulic turbine with interblade vortex suppressor |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2436670C (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102536591B (en) * | 2012-02-07 | 2014-04-16 | 戴会超 | Mixed-flow type water turbine for increasing survival rate of fishes |
| PT2873851T (en) | 2013-11-14 | 2016-10-25 | Alstom Renewable Technologies | Aerating system for hydraulic turbine |
| CH714298B1 (en) * | 2017-11-03 | 2024-05-15 | Arif Khan | Small hydroelectric power plant. |
| CN116241403A (en) * | 2023-03-01 | 2023-06-09 | 清华大学 | Runner and mixed-flow water turbine |
| WO2025179370A1 (en) * | 2024-02-27 | 2025-09-04 | Andritz Canada Inc. | Turbine runner flow deflectors |
-
2003
- 2003-08-07 CA CA2436670A patent/CA2436670C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CA2436670A1 (en) | 2005-02-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101349167B (en) | Axial Turbine | |
| KR100254284B1 (en) | Turbine nozzles and turbine rotor blades of axial flow turbine | |
| US5441384A (en) | Hydraulic turbine and guide gate apparatus and runner apparatus therefor | |
| US7736128B2 (en) | Stress relief grooves for Francis turbine runner blades | |
| CN110513329B (en) | Axial-flow wind wheel and air conditioner with same | |
| EP3172431B1 (en) | Francis turbine with short blade and short band | |
| CA2436670C (en) | Hydraulic turbine with interblade vortex suppressor | |
| JP4280127B2 (en) | Francis-type runner | |
| US6334757B1 (en) | Water turbine | |
| JP5135296B2 (en) | Turbine cascade, turbine stage using the same, axial turbine | |
| JP2009185731A (en) | Valve turbine | |
| JP3822416B2 (en) | Francis type pump turbine | |
| US1748892A (en) | Hydraulic process and apparatus | |
| JPH10318117A (en) | Fluid machinery impeller | |
| JP2010101265A (en) | Runner of francis type hydraulic machine and francis type hydraulic machine | |
| JP4768361B2 (en) | Francis type runner and hydraulic machine | |
| JP4240728B2 (en) | 3D axial flow turbine | |
| JPH0478803B2 (en) | ||
| JP4751165B2 (en) | Francis pump turbine | |
| JPH0335511B2 (en) | ||
| US11913426B2 (en) | Rotor blade for a wind turbine and wind turbine | |
| CN213088334U (en) | Axial flow compressor rectifier | |
| JP2013142356A (en) | Axial flow water turbine | |
| JP2004156587A (en) | Hydraulic turbine | |
| CN218062783U (en) | Semi-open type centrifugal pump impeller |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |
Effective date: 20150807 |