CN213598113U - Through-flow turbine capable of inhibiting gap cavitation of runner - Google Patents

Abstract

The utility model relates to a can restrain through-flow turbine of runner clearance cavitation, holistic structure includes the runner of intaking, it has bulb body and wheel hub body to distribute in proper order along the center pin direction of the runner of intaking, be provided with round swing guide vane on the bulb body, the wheel hub body other end extends to the tail water pipeline section always, be connected with the runner on the wheel hub body, the runner is located the runner indoorly, annular air supplement pipe is installed to runner outdoor wall, annular air supplement pipe passes through support welded fastening on the runner outdoor wall, annular air supplement pipe passes through air inlet valve and is connected with external gas transmission device, runner outdoor wall is opened there is the aperture, be connected with annular air supplement pipe through air inlet valve. The external gas transmission device inputs high-pressure gas into the annular gas supplementing pipeline through the gas inlet valve, and then the annular gas supplementing pipe injects the gas into the runner chamber from the small hole in the outer wall of the runner chamber through the gas inlet valve, so that the pressure at the lowest pressure in the runner chamber is increased, the occurrence of clearance cavitation is inhibited, and the running stability of the through-flow turbine is improved.

Description

Through-flow turbine capable of inhibiting gap cavitation of runner

Technical Field

The utility model belongs to the technical field of the hydraulic turbine, concretely relates to can restrain through-flow turbine of runner clearance cavitation.

Background

With the gradual promotion of China to the goal of building oceans in the strong country, China pays more and more attention to the development and utilization of ocean resources. Among them, ocean energy is the most important part in the development of ocean resources. Tidal energy has received attention from experts and scholars in various countries as a highly efficient and clean marine energy source. When generating electricity from tidal energy, the turbine is one of the main units for converting tidal energy into electrical energy. However, in the operation of the through-flow turbine, because a gap exists between the blade top of the runner of the through-flow turbine and the inner wall of the runner chamber, when water flows through the blade top gap between the runner and the runner chamber, the local flow velocity is increased and the pressure is reduced, so that the through-flow turbine often generates gap cavitation. The flow phenomenon not only induces cavitation erosion, vibration and noise of the runner blades to further influence the safe and stable operation of the through-flow turbine, but also relates to various flow problems such as blade tip leakage vortex, blade tip separation vortex, multiphase flow and the like to deteriorate the performance of the through-flow turbine. Therefore, it is very important to deeply study the clearance cavitation of the through-flow turbine and improve the influence of the clearance cavitation on the operation stability of the turbine.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a can restrain through-flow turbine of runner clearance cavitation has improved local velocity of flow increase and pressure when the blade top clearance between runner and the runner room and has reduced gradually, and the through-flow turbine clearance cavitation problem that leads to has improved the stability of through-flow turbine operation.

The technical scheme adopted by the utility model is that the through-flow turbine capable of inhibiting the cavitation of the runner gap comprises a water inlet runner, wherein one end close to the water inlet runner is sequentially communicated with a runner chamber and a tail water pipe section; a bulb body and a hub body are sequentially distributed along the direction of a central shaft of the water inlet flow passage, the other end of the hub body extends to the tail water pipe section, and a circle of movable guide vanes are arranged on the bulb body; the outer wall of the runner chamber is provided with an annular air supplement pipe, the annular air supplement pipe is welded and fixed on the outer wall of the runner chamber through a fixing bracket, the annular air supplement pipe is connected with an external air transmission device, and the outer wall of the runner chamber is provided with a small hole and is connected with the annular air supplement pipe through an air inlet valve.

The utility model is also characterized in that,

a rotating wheel is arranged in the rotating wheel chamber.

The outer wall of the runner chamber is provided with 9 small holes, each 3 small holes form a group, the included angle between adjacent central small holes is 120 degrees, the small holes are uniformly distributed along the outer wall of the runner chamber, the interval of the small holes in the same group is 0.01D, the diameter of each small hole is 0.001D, and D is the diameter of the runner.

The distance between the circle center of the section ring of the annular air supplement pipe and the central axis of the through-flow turbine is 1.5D.

The movable guide vane is a fully-opened guide vane.

The annular air supplement pipe is welded on the outer wall of the runner chamber through a steel bracket;

the beneficial effects of the utility model are that, in external gas transmission device passes through admission valve with high-pressure gas and inputs annular tonifying qi pipeline with the air, then annular tonifying qi pipe through admission valve with gaseous from the runner house outer wall aperture squeeze into the runner house, and then promoted the pressure of the lower of pressure in the runner house, restrained the emergence of clearance cavitation to the stability of through-flow turbine operation has been improved.

Drawings

FIG. 1 is a schematic structural view of a tubular turbine capable of suppressing cavitation in the clearance of a runner according to the present invention;

FIG. 2 is a schematic view showing the arrangement of an annular air supply pipe of a tubular turbine capable of suppressing cavitation in the gap between the runner according to the present invention;

FIG. 3 is a schematic view of a small hole on the outer wall surface of a runner chamber of a tubular turbine capable of suppressing clearance cavitation of the runner according to the present invention;

FIG. 4 is a schematic view of the size of the small hole on the outdoor wall surface of the runner of the tubular turbine capable of suppressing the cavitation of the runner gap according to the present invention;

in the figure, 1, a water inlet flow passage, 2, a bulb body, 3, a movable guide vane, 4, an annular air supplement pipe, 5, a rotating wheel, 6, a rotating wheel chamber, 7, a hub body, 8, a tail water pipe section, 9, an air inlet valve, 10, a small hole and 11 are fixed supports.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

The utility model relates to a through-flow turbine capable of inhibiting cavitation of runner gaps, as shown in figure 1, comprising a water inlet runner 1, wherein one end close to the water inlet runner 1 is sequentially communicated with a runner chamber 6 (as shown in figure 2) and a tail water pipe section 8; a bulb body 2 and a hub body 7 are sequentially distributed along the central axis direction of the water inlet flow channel 1, the other end of the hub body 7 extends to a tail water pipe section 8, and a circle of movable guide vanes 3 are arranged on the bulb body 2; annular air supplement pipe 4 is installed to runner chamber 6 outer wall, annular air supplement pipe 4 passes through fixed bolster 11 welded fastening on the runner chamber outer wall, annular air supplement pipe 4 is connected with external gas transmission device, runner chamber 6 outer wall is opened there is aperture 10 (as shown in fig. 3), is connected with annular air supplement pipe 4 through air inlet valve 9.

A runner 5 is arranged in the runner chamber 6.

The outer wall of the runner chamber 6 is provided with 9 small holes, each 3 small holes form a group, the included angle between adjacent central small holes is 120 degrees, the small holes are uniformly distributed along the outer wall of the runner chamber 6, the interval between the small holes in the same group is 0.01D, the diameter of each small hole is 0.001D, and D is the diameter of the runner (as shown in figure 4).

An annular air supplement pipe 4 is arranged on the outer wall of the runner chamber 6, and the annular air supplement pipe 4 is connected with an external air conveying device through an air inlet valve 9;

the small hole on the outer wall of the runner chamber 6 is connected with the annular air supplement pipe 4 through an air inlet valve 9;

the distance between the circle center of the circular ring of the section of the annular air supplement pipe 4 and the horizontal axis of the through-flow turbine is 1.5D;

the utility model relates to a can restrain through-flow turbine of runner clearance cavitation's theory of operation as follows:

when the through-flow turbine operates, water flow enters the movable guide vane 3 from the water inlet flow channel 1, the movable guide vane 3 guides the water flow into the rotating wheel 5 and drives the rotating wheel 5 to rotate, then the water flow enters the draft tube 7 through the gap between the runner 5 and the blade of the rotating wheel 5 and the rotating wheel chamber 6, the flow speed is accelerated when the water flow flows through the gap between the rotating wheel 5 and the rotating wheel chamber 6, gap leakage vortex is easy to generate, particularly under the non-design working condition, cavitation is easy to occur at the gap, and the gap of the rotating wheel chamber is pressurized through the air supplementing device to enable the pressure to be higher than the initial cavitation pressure, so that the cavitation at the gap is. The specific implementation method is that firstly, the external gas transmission device sends gas into the annular gas supplementing pipe 4 through the gas inlet valve 9, then the annular gas supplementing pipe 4 pumps the gas into the runner chamber 6 through the small hole 9 through the gas inlet valve 9, so that the pressure in the runner chamber 6 is improved, and the occurrence of gap cavitation is restrained.

Claims (5)

1. A through-flow turbine capable of inhibiting cavitation of a runner gap is characterized by comprising a water inlet runner (1), wherein one end close to the water inlet runner (1) is sequentially communicated with a runner chamber (6) and a tail water pipe section (8); a bulb body (2) and a hub body (7) are sequentially distributed along the central axis direction of the water inlet flow channel (1), the other end of the hub body (7) extends to a tail water pipe section (8), and a circle of movable guide vanes (3) are arranged on the bulb body (2); annular air supplement pipe (4) are installed to runner room (6) outer wall, annular air supplement pipe (4) are through fixed bolster (11) welded fastening on the runner room outer wall, annular air supplement pipe (4) are connected with external gas transmission device, runner room (6) outer wall is opened there is aperture (10), is connected with annular air supplement pipe (4) through air inlet valve (9).

2. A flow turbine according to claim 1, wherein the runner (5) is disposed in the runner chamber (6).

3. The through-flow turbine capable of inhibiting cavitation of runner gaps as claimed in claim 2, wherein the outer wall of the runner chamber (6) is provided with 9 small holes, each 3 small holes are in a group, the included angle between adjacent central small holes is 120 degrees, the central small holes are uniformly distributed along the outer wall of the runner chamber (6), the interval of the small holes in the same group is 0.01D, the diameter of the small holes is 0.001D, and D is the diameter of the runner.

4. A flow turbine according to claim 2, wherein the distance between the center of the circular ring of the section of the annular air supply pipe (4) and the central axis of the flow turbine is 1.5D.

5. A flow turbine according to claim 2, wherein the movable guide vanes (3) are full open guide vanes.

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