CN111535984A - Cross-shaft tidal current energy water turbine with passive pitching adjusting device - Google Patents

Abstract

The invention belongs to the technical field of horizontal-axis tidal current energy turbines, and in particular relates to a horizontal-axis tidal current energy hydraulic turbine with a passive pitch adjustment device. The horizontal-axis tidal current energy turbine includes turbine blades, a hub, a nacelle and a passive pitch adjustment device. The turbine blades are fixedly connected to the first end of the engine room through the hub. The hub, the engine room and the passive pitch adjustment device are located on the same horizontal line to form the main shaft; passive pitch adjustment The device includes a connecting rod, an adjusting blade and a counterweight located in the adjusting blade for adjusting the weight of the passive pitch adjusting device, the first end of the connecting rod is fixedly connected with the second end of the nacelle, and the second end is fixedly connected with the adjusting blade; The blade is a closed structure composed of multiple airfoils for generating lift. By changing the structure of the adjusting blade and the weight of the counterweight, the horizontal axis tidal current energy turbine is kept in a balanced state. The sweep plane of the turbine is always perpendicular to the incoming flow direction, which improves the energy utilization efficiency of tidal energy.

Description

A horizontal-axis tidal current energy turbine with passive pitch adjustment device

technical field

The invention belongs to the technical field of horizontal-axis tidal current energy turbines, and in particular relates to a horizontal-axis tidal current energy hydraulic turbine with a passive pitch adjustment device.

Background technique

Energy is a necessity of our life and a strategic resource for national development. Since fossil energy is limited and will produce a lot of pollution in the process of consumption, it is imperative to develop and utilize various forms of renewable energy.

Tidal energy is a clean and renewable energy with the characteristics of large reserves, good predictability and high energy density. It is an ideal alternative to fossil energy resources. Among them, the horizontal-axis tidal energy turbine is a device that utilizes tidal energy, which can convert the tidal energy into the kinetic energy of the turbine, and then into electrical energy.

However, when the horizontal-axis tidal energy turbine obtains energy from the tidal current, its efficiency will be reduced because the direction of the tidal current is not perpendicular to the swept plane of the turbine blades.

SUMMARY OF THE INVENTION

(1) Technical problems to be solved

Aiming at the existing technical problems, the present invention provides a horizontal-axis tidal current energy turbine with a passive pitch adjustment device.

(2) Technical solutions

The present invention provides a transverse-axis tidal current energy turbine with a passive pitch adjustment device, comprising a turbine blade, a hub, a nacelle and a passive pitch adjustment device. The pitch adjustment device is located on the same horizontal line, forming the main axis;

The passive pitch adjustment device includes a connecting rod, an adjustment blade and a counterweight located in the adjustment blade for adjusting the weight of the passive pitch adjustment device. The first end of the connecting rod is fixedly connected with the second end of the nacelle, and the second end Fixed connection with the adjusting blade;

The regulating blade is an airtight structure composed of multiple airfoils for generating lift. By changing the structure of the regulating blade and the weight of the counterweight, the horizontal-axis tidal current energy turbine is kept in a balanced state.

Preferably, the weights are evenly distributed in the adjusting blade.

Preferably, the counterweight is arranged at the center of the adjusting blade.

Preferably, a vertical support and a cabin support are also included, the cabin support is a concave structure, and the bottom of the concave structure is fixedly connected to the vertical support.

Preferably, the side wall of the nacelle is provided with a nacelle connecting shaft, and the nacelle connecting shaft is rotatably connected to the nacelle bracket through a radial bearing.

Preferably, the rotation angle of the rotation connection is -24°˜24°, and the rotation angle is the included angle between the main shaft and the horizontal plane.

Preferably, a generator and a transmission mechanism are also included, and the generator and transmission mechanism are arranged inside the nacelle and are fixedly connected to the wheel hub.

Preferably, the connecting rod is a telescopic connecting rod.

Preferably, the adjusting vanes are made of corrosion-resistant materials.

(3) Beneficial effects

In the transverse-axis tidal current energy turbine provided by the present invention, the hub, the engine room and the passive pitch adjusting device are arranged in sequence to form the main shaft. The passive pitch adjustment device includes a cabin connecting shaft, a cabin bracket, a connecting rod, an adjustment blade and a counterweight, the adjustment blade is designed as a closed structure composed of multiple airfoils for generating lift, and the adjustment blade has a built-in counterweight , the passive pitch adjustment device helps the horizontal-axis tidal current turbine to adjust the pitch angle of the turbine according to the direction of the incoming flow, and finally realizes the passive adjustment of the sweep plane of the turbine blades with the direction of the incoming flow, so that the direction of the incoming flow is always perpendicular to the sweep plane, thereby improving the turbine efficiency. At the same time, the passive pitch adjusting device in the present invention has a simple structure, low installation, maintenance and use costs.

Description of drawings

Fig. 1 is the structural representation of the horizontal axis tidal current energy turbine provided by the present invention;

Fig. 2 is a schematic diagram of a horizontal-axis tidal current energy turbine and an incoming flow angle provided by the present invention;

Fig. 3 is the initial state force diagram of the horizontal-axis tidal current energy turbine provided by the present invention.

[Description of reference numerals]

1: turbine blade;

2: hub;

3: vertical bracket;

4: cabin bracket;

5: Radial bearing;

6: Engine room connecting shaft;

7: cabin;

8: connecting rod;

9: Adjust the blade;

Ⅰ: The incoming flow is parallel to the main axis;

Ⅱ: The angle between the incoming flow and the main shaft is negative;

Ⅲ: The angle between the incoming flow and the main shaft is positive;

L1: The distance from the center of gravity of the hub and turbine blades to the connecting shaft of the nacelle;

L2: The distance from the connecting shaft of the nacelle to the center of gravity of the adjusting blade and counterweight;

Mg: Adjust the total weight of the blade and internal counterweight;

M ₁ g: total weight of turbine blades and hub;

F: Adjust the lift that the blade is subjected to.

Detailed ways

In order to better explain the present invention and facilitate understanding, the present invention will be described in detail below with reference to the accompanying drawings and through specific embodiments.

As shown in FIG. 1 , the horizontal-axis tidal current energy turbine with passive pitch adjustment device provided by the present invention includes a generator, a turbine blade 1, a hub 2, a vertical support 3, a nacelle support 4, a nacelle connecting shaft 6, a nacelle 7, Connecting rod 8, adjusting blade 9 and counterweight. Among them, the nacelle bracket 4, the nacelle connecting shaft 6, the connecting rod 8, the adjusting blade 9 and the counterweight together constitute a passive pitch adjusting device.

The hub 2, the nacelle 7 and the connecting rod 8 are sequentially connected detachably and fixedly, and the axes of the hub 2, the nacelle 7 and the connecting rod 8 are on the same horizontal line, forming the main shaft of the transverse-axis tidal energy turbine. Preferably, the connecting rod 8 is a telescopic connecting rod, and the length of the connecting rod 8 can be adjusted according to actual needs.

The turbine blades 1 are evenly distributed on the side of the hub 2 and are detachably and fixedly connected to the hub 2 . The turbine blades 1, the hub 2, the generator and the transmission mechanism constitute the rotating energy-absorbing part of the horizontal-axis tidal current energy turbine. The other end of the nacelle 7 is detachably and fixedly connected with one end of the connecting rod 8 . The other end of the connecting rod 8 is detachably and fixedly connected with the adjusting blade 9 .

Further, the number of water turbine blades 1 can be selected according to the requirements in actual operation, and the geometry parameters such as airfoil shape, chord length distribution, and torsion angle distribution involved in the water turbine blade 1 are not specifically limited in the present invention.

A nacelle connecting shaft 6 is provided on the side wall of the nacelle 7 , and the nacelle connecting shaft is rotatably connected to the nacelle bracket 4 through a radial bearing 5 . One end of the vertical support 3 is used for fixed connection with the seabed, and the other end is used for detachable fixed connection with the nacelle support 4 . The nacelle bracket 4 is a concave structure, and the concave structure includes two oppositely arranged side surfaces and a bottom surface integrated with the side surfaces. The bottom surface of the concave structure is detachably and fixedly connected with the vertical support 3 . Each side of the concave structure is provided with a slot hole for connecting with the nacelle connecting shaft 6, and the radial bearing 5 is fixedly connected with the nacelle connecting shaft 6 through the slot hole, so as to realize the rotational connection between the nacelle bracket 4 and the nacelle 7, so that the The nacelle 7 is rotatable above the nacelle bracket 4 with the nacelle connecting shaft 6 as the center of rotation. The rotation angle is the included angle between the main shaft and the horizontal plane, and the rotation range is between -24° and 24°.

Further, the adjusting blade 9 is a closed structure composed of a plurality of airfoils for generating lift. A counterweight is arranged in the regulating blade 9, and the regulating blade 9 and the counterweight together play the role of regulating the pitch operation of the water turbine. The counterweight can be evenly distributed in the adjusting blade 9 , or can be arranged in the center of the adjusting blade 9 .

The magnitude of the lift force F received by the regulating blade 9 varies with the angle of attack (the angle between the incoming velocity vector and the chord line of the regulating blade 9) on the regulating blade 9: when the angle of attack increases, the lifting force on the regulating blade 9 increases. ; When the angle of attack decreases, the lift force on the regulating blade 9 decreases.

As shown in Figure 2, the initial installation of the horizontal-axis tidal current turbine provided by the present invention should meet the following conditions: when the incoming flow speed is the rated speed and the incoming flow direction is parallel to the main shaft (as shown in Figure 2, I), The main shaft is perpendicular to the vertical support 3, and the horizontal axis tidal current energy turbine satisfies the following relationship:

M ₁ g×L1=(Mg–F)×L2 (1)

Among them, L1 is the distance from the center of gravity of the hub and turbine blades to the connecting shaft of the nacelle; L2 is the distance from the connecting shaft of the nacelle to the center of gravity of the adjusting blade and the counterweight; Mg is the total weight of the adjusting blade and the counterweight; M ₁ g is the The total weight of the turbine blades and the hub; F is the lift force on the adjustment blades. The present invention does not specifically limit the above-mentioned L1, L2, Mg and M ₁ g, which can be designed and adjusted according to the actual situation, as long as the horizontal axis tidal current energy turbine satisfies the balance relationship of formula (1).

working principle

When the horizontal-axis tidal current turbine is running, the turbine blades need to face the incoming flow direction to achieve the optimal working state. As shown in Fig. 3, when the incoming flow is parallel to the main shaft (as shown in Fig. 3 I), the passive pitch adjustment device does not work, and the horizontal-axis tidal current turbine is in a balanced state.

When the angle between the incoming flow and the main shaft is negative (as shown in II in Figure 3), the angle of attack on the adjusting blade 9 increases, and the lift force on the adjusting blade 9 increases. At this time, the force on the horizontal-axis tidal current turbine satisfies the following relationship:

M ₁ g×L1>(Mg–F)×L2 (2)

The force change of the adjusting blade 9 causes the hub 2, the nacelle 7, the connecting rod 8 and the adjusting blade 9 to rotate counterclockwise (planning direction) around the connecting shaft 6 of the nacelle, the position of the adjusting blade 9 rises, the position of the turbine blade 1 becomes lower, and finally the horizontal When the axial flow energy turbine is stressed again, the sweep plane of the turbine blade 1 is perpendicular to the current incoming flow.

When the angle between the incoming flow and the main shaft is positive (as shown by III in Figure 3), the angle of attack on the regulating blade 9 decreases, and the lift on the regulating blade 9 decreases. At this time, the force on the horizontal-axis tidal current turbine satisfies the following relationship :

M ₁ g×L1<(Mg–F)×L2 (3)

The force change of the adjusting blade 9 causes the hub 2, the nacelle 7, the connecting rod 8 and the adjusting blade 9 to rotate clockwise (looking up direction) around the connecting shaft 6 of the nacelle, the position of the adjusting blade 9 becomes lower, the position of the turbine blade 1 is raised, and finally the horizontal When the axial flow energy turbine is stressed again, the sweep plane of the turbine blade 1 is perpendicular to the current incoming flow.

The horizontal-axis tidal current energy turbine provided by the present invention utilizes a passive pitch adjustment device without the aid of an additional power mechanism, so that the sweeping plane of the hydraulic turbine in the pitch direction is perpendicular to the incoming flow direction, and the energy utilization efficiency of the tidal current energy is improved. .

The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are only for explaining the principles of the present invention, and cannot be interpreted as limiting the protection scope of the present invention in any way. Based on the explanations herein, those skilled in the art can think of other specific embodiments of the present invention without creative efforts, and these methods will all fall within the protection scope of the present invention.

Claims (9)

1. A horizontal-axis tidal current energy water turbine with a passive pitch adjusting device comprises water turbine blades (1), a hub (2) and a cabin (7), wherein the water turbine blades (1) are connected with a first end of the cabin (7) through the hub (2), and the horizontal-axis tidal current energy water turbine is characterized by further comprising the passive pitch adjusting device, wherein the hub (2), the cabin (7) and the passive pitch adjusting device are located on the same horizontal line to form a main shaft;

the passive pitch adjusting device comprises a connecting rod (8), an adjusting blade (9) and a counterweight which is positioned in the adjusting blade (9) and used for adjusting the weight of the passive pitch adjusting device, wherein the first end of the connecting rod (8) is connected with the second end of the engine room (7), and the second end of the connecting rod is connected with the adjusting blade (9);

the adjusting blade (9) is a closed structure which is composed of a plurality of wing surfaces and used for generating lift force, and the cross-shaft tidal current energy water turbine is kept in a balanced state by changing the weight of the structure (9) of the adjusting blade and the weight of the counterweight.

2. A transverse axis tidal current energy turbine according to claim 1, characterized in that the counterweights are evenly distributed within the regulating blades (9).

3. A transverse axis tidal current energy turbine according to claim 1, characterized in that the counterweight is arranged at the center of the regulating blade (9).

4. The cross-axis tidal current energy water turbine as set forth in claim 1, further comprising a vertical support (3) and a nacelle support (4), wherein the nacelle support (4) is a concave structure, and the bottom of the concave structure is connected with the vertical support (3).

5. The transverse-axis tidal current energy water turbine as set forth in claim 4, characterized in that the side wall of the nacelle (7) is provided with a nacelle connecting shaft (6), the nacelle connecting shaft (6) being rotationally connected with a nacelle stand (4) by means of a radial bearing (5).

6. The transverse-axis tidal current energy water turbine as set forth in claim 5, wherein the rotation angle of the rotary connection is-24 ° to-24 °, and the rotation angle is an included angle between the main axis and the horizontal plane.

7. The transverse-axis tidal current energy water turbine as set forth in claim 1, further comprising a generator and a transmission mechanism, which are disposed inside the nacelle (7) and connected to the hub (2).

8. A transverse-axis tidal current energy water turbine according to claim 1, characterized in that the connecting rods (8) are telescopic connecting rods.

9. A transverse-axis tidal current energy turbine according to claim 1, characterized in that the regulating blades (9) are made of corrosion-resistant material.

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