JPS61229976A - Water turbine or pump turbine - Google Patents

Abstract

PURPOSE:To suppress vibration of a runner, by dividing a guide vane into upper and lower members to thereby make uniform a distribution of pressure fluctuation in a flow line by the guide vane and reduce a fluctuation range of an external force to be received by the runner. CONSTITUTION:Guide vanes are provided along a circumference of runners at regular intervals, and are divided into upper and lower members. The upper guide vanes 8 and the lower guide vanes 9 are alternately arranged along the circumference of the runners. A pressure distribution in a flow line shown by an isobar b is such that a pressure fluctuation range is reduced along the circumference.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a water turbine or a pump water turbine.

(Prior Art) Examples of conventional water turbines or pump water turbines are shown in FIGS. 4 to 7, where l is a runner, 2 is a runner vane, and 3 is a runner vane arranged around the runner l at a predetermined interval along the circumferential direction. A large number of guide vanes are arranged, 4 is a volute arranged around the guide vane 3, 5 is a guide vane support shaft, and 6 is a draft tube.

When operating as a water turbine, water flowing from the volute 4 in the direction of the solid arrow is guided by the guide vane 3.
It flows from the outer circumference of the runner 1 into the runner vane 2 at a predetermined inflow angle, and in the process of flowing through the runner 1, the energy it possesses is given to the runner l to rotate it in the direction of the solid line arrow, and then, It flows out through the draft tube 6.

When operating as a pump-turbine, the runner 1 is rotated in the direction of the dashed arrow, and as a result, the water flowing in from the draft tube 6 is turned into an enemy while flowing through the runner 1, and the water flowing out from the runner 1 is It is smoothly guided by the guide vane 3, flows into the volute 4, and is sent in the direction of the dashed arrow.

(Problems to be Solved by the Invention) In the above-mentioned conventional water turbine, as shown in FIG.
The pressure distribution at the outlet on the runner 1 side of the flow path 7 bounded by the guide vane 3 is maximum at the center of each flow path 7, as is clear from the isobars a, and becomes smaller as it approaches the periphery. Thus, when the runner 1 is rotating, the runner vanes 2 pass successively across each of these pressure distribution channels 7, so that each runner vane 2
receives a fluctuating external force of the period required for passing from one guide vane 3 to the next guide vane 3, and the runner 1 vibrates. This vibrational force increases as the water wheel becomes larger.

To deal with this, it has been proposed to mechanically increase the vibration intensity of the runner 1, but this not only increases cost but also
This was difficult to implement due to structural constraints.

(Means for Solving the Problems) The present invention was invented to solve the above problems, and the gist thereof is that the runners are arranged around the runners at predetermined intervals along the circumferential direction. A water turbine or a pump water turbine is characterized in that a large number of guide vanes are divided into upper and lower stages, and the upper and lower guide vanes are alternately arranged along the circumferential direction.

Embodiment One embodiment of the invention is shown in FIGS. 1-3.

Figure 1 is a developed view of the guide vane group, Figure 2 is the same as Figure 1.
FIG. 3 is a view taken along line m--m in FIG. 2;

As is clear from FIGS. 1 to 3, the guide vane is divided into upper and lower stages, and the upper guide vanes 8 and lower guide vanes 9 are arranged alternately along the circumferential direction, that is, adjacent upper guide vanes 8 The lower guide vane 9 is arranged in between, the upper guide vane 8 is rotatably supported around the support shaft 5, and the lower guide vane 9 is rotatably supported around the support shaft 16. There is. Both left and right ends of the lower end surface of the upper guide vane 8 are pins 10 and 11.
The left and right ends of the upper end surface of the lower guide vane 9 adjacent to the upper guide vane 8 are rotatably connected to two links 12.13 arranged in parallel via 714.1.
5 to the two links 12, 13 so as to be rotatable. Thus, by rotating the support shaft 5, the rotational force is applied to the upper guide vane 8 and the pin 1O11.
1, two links 12.13 and pin 14.15 to the lower guide vane 9, and the upper guide vane
The vane 8 and the lower guide vane 9 simultaneously rotate in the same direction and at the same angle.

Thus, during operation, the pressure distribution at each runner outlet of the flow path 17 bounded by the upper guide vane 8 and the flow path 18 bounded by the lower guide vane 9 becomes as shown by the isobars in FIG. Some of the equal pressure lines are formed alternately and continuously in the upper channel 17 and the lower channel 18. Therefore, when the runner rotates and the runner vanes successively pass across these channels 17 and 18, the period of the fluctuating external force received is half that of the conventional force shown in FIGS. 4 to 7. It becomes much smaller during fluctuations.

(Operations and Effects of the Invention) In the present invention, a large number of guide vanes arranged at predetermined intervals along the circumferential direction around the runner are divided into upper and lower stages, and these divided upper stage guide vanes and lower stage guide vanes are divided into upper and lower stages. Because the guide vanes are arranged alternately along the circumferential direction, during operation, some of the isobar lines on the runner side of the upper flow path limited by the upper guide vanes and the lower flow path limited by the lower guide vanes are not connected to the upper flow path. They are formed alternately and continuously in the lower flow path, and therefore, when the runner rotates and its runner vanes successively pass across the upper flow path and the lower flow path, the fluctuation of the external force that the runner receives is significantly reduced. be done. As a result, the vibration of the runner can be suppressed easily and inexpensively without mechanically increasing the vibration intensity of the runner.

[Brief explanation of the drawing]

1 to 3 show one embodiment of the present invention, in which FIG. 1 is a developed view of a group of guide vanes, FIG. 2 is a view taken along the line ■-■ in FIG. 1, and FIG. FIG. 2 is a view taken along the line ■-m in FIG. 2; Figures 4 to 7 show an example of a conventional water turbine or pump water turbine, with Figure 4 being a schematic cross-sectional view, Figure 5 being a schematic longitudinal sectional view, and Figure 6 showing a group of guide vanes. The developed view, FIG. 7, is a plan view of the guide vane.

Claims (1)

[Claims] A large number of guide vanes arranged around the runner at predetermined intervals along the circumferential direction are divided into two stages, upper and lower, and these divided upper and lower guide vanes are arranged alternately along the circumferential direction. A waterwheel or pump-turbine characterized by: