Front prerotation guide wheel

Abstract

The invention provides a front prewhirl guide wheel which comprises a first enclosure bulkhead structure arranged at the tail of a ship, second enclosure bulkhead structures are arranged between the two ends of the first enclosure bulkhead structure and a tail shaft pipe correspondingly, and the first enclosure bulkhead structure, the second enclosure bulkhead structures and the tail shaft pipe of the ship jointly define an enclosure bulkhead space; a guide vane is arranged on the first enclosure bulkhead structure; the first enclosure bulkhead structure comprises a left enclosure bulkhead body and a right enclosure bulkhead body, and the expansion angle of the left enclosure bulkhead body is larger than that of the right enclosure bulkhead body. According to the invention, after a water body passes through the enclosure bulkhead space, under the prerotation action of the guide vanes, incoming flow of the propeller is more uniform and stable, the speed is increased, the relative tangential speed between the incoming flow and the propeller is increased, and the efficiency of the propeller is improved; the influence caused by different screw pitches of the propeller at different radiuses is considered, the second enclosure bulkhead structure and the guide vanes are twisted to different degrees according to the screw pitches, the efficiency of the propeller is further improved, and the energy-saving effect is improved.

Description

Technical Field

[0001] The invention relates to the technical field of ships, and in particular to a front pre-rotation guide wheel. Background Art

[0002] The propeller is the main propulsion form of modern ships. Through the rotation of the propeller, work is done on the water and forward thrust is obtained. However, the existing ship propellers have the following problems when working: 1. The flow field at the tail of the ship, especially the flow field in the area in front of the propeller, is not uniform enough, and the incoming flow speed in the upper half of the propeller space is slow, which leads to a decrease in propeller efficiency, and the power generated by the engine cannot be converted into thrust to the maximum extent, resulting in the engine needing to provide more energy to maintain the same speed; 2. Since the pitch of the propeller is different at different radii, the previous design of the propeller front device did not consider the impact caused by the different pitches, so the maximum effect of the propeller front pre-rotation guide wheel cannot be exerted, reducing the energy saving effect. Summary of the invention

[0003] The purpose of the present invention is to solve the deficiencies in the prior art and provide a front pre-rotation guide wheel.

[0004] The objective of the present invention is achieved through the following technical solutions: a front pre-rotation guide wheel, comprising a first enclosure structure arranged at the stern of a ship, a second enclosure structure is respectively arranged between the two ends of the first enclosure structure and the stern tube, and the first enclosure structure, the second enclosure structure and the stern tube of the ship are jointly enclosed to form an enclosure space; a guide vane is arranged on the first enclosure structure, and water body pre-rotates after passing through the guide vane, and the pre-rotation direction of the water body is opposite to the rotation direction of the propeller;

[0005] The first surrounding wall structure includes a left surrounding wall body and a right surrounding wall body, and an expansion angle of the left surrounding wall body is greater than an expansion angle of the right surrounding wall body.

[0006] Preferably, the expansion angle of the right surrounding wall is 0-60°, and the expansion angle of the left surrounding wall is 90°-120°.

[0007] Preferably, the second surrounding wall structures at both ends of the first surrounding wall structure are airfoil structures with a twist angle, the second surrounding wall structure is connected to the first surrounding wall structure, and one end of the second surrounding wall structure is connected to the outer surface of the stern tube of the ship; the twist angle of the second surrounding wall structure from one end to the other end is 0-20 degrees.

[0008] Preferably, the outer surface of the first surrounding wall structure is a conical surface, and the taper range of the outer surface of the first surrounding wall structure is 1:5 to 1:20.

[0009] Preferably, the cross-sections of the first surrounding wall structure and the second surrounding wall structure are airfoil structures, and the chord length of the cross-sections is between 0.8 and 2.5 times the length of the propeller hub.

[0010] Preferably, 2-3 guide vanes are provided on the first surrounding wall structure, and the interval angle between two adjacent guide vanes is 25° to 45°.

[0011] Preferably, one end of the guide vane is connected to the stern tube of the ship, and the other end of the guide vane is fixed to the inner wall of the first surrounding wall structure, and the torsion angle of the guide vane from one end to the other end is 0° to 10°.

[0012] Preferably, one end of the guide vane is connected to the stern tube of the ship, the other end of the guide vane is higher than the outer side of the first surrounding wall structure, and the guide vane part is located in the surrounding wall space.

[0013] Preferably, a transition connection structure is provided between the guide vane and the outer side of the first surrounding wall structure.

[0014] The beneficial effects of the present invention are:

[0015] 1. In the present invention, after the water body passes through the enclosed wall space, under the pre-rotation effect of the guide vane, the incoming flow of the propeller becomes more uniform and stable, the speed is improved, and the relative tangential speed between the incoming flow and the propeller is increased, thereby improving the efficiency of the propeller.

[0016] 2. The present invention takes into account the influence caused by the different pitches of the propeller at different radii. The second surrounding wall structure and the guide vanes are twisted to different degrees according to the pitch, which further improves the efficiency of the propeller and improves the energy-saving effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of Example 1 of the present invention.

[0018] Figure 2 It is a front view of embodiment 1 of the present invention.

[0019] Figure 3 It is a cross-sectional view of the first surrounding wall structure in Example 1 of the present invention.

[0020] Figure 4 It is a cross-sectional view of the guide vane in Example 1 of the present invention.

[0021] Figure 5 This is the velocity cloud diagram of the water flow along the propeller circumference at the propeller disk when no pre-swirl guide wheel is installed.

[0022] Figure 6 This is the velocity cloud diagram of the water flow along the propeller circumference at the propeller disk after setting the front pre-rotation guide wheel.

[0023] Figure 7 This is a schematic diagram of the structure of Example 2 of the present invention.

[0024] In the figure: 1. tail tube, 2. first surrounding wall structure, 2-1. left surrounding wall body, 2-2. right surrounding wall body, 3. second surrounding wall structure, 4. guide vane, 5. longitudinal center axis of tail tube, 6. transition connection structure. DETAILED DESCRIPTION

[0025] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0026] Those skilled in the art should understand that, in the disclosure of the present invention, the orientation or position relationship indicated by the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0027] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0028] Embodiment 1:

[0029] like Figures 1 to 6 As shown, a front pre-spin guide wheel comprises a first enclosure structure 2 arranged at the stern of a ship, a second enclosure structure 3 is respectively arranged between the two ends of the first enclosure structure 2 and the stern tube 1, and the first enclosure structure 2, the second enclosure structure 3 and the stern tube 1 of the ship are enclosed together to form an enclosure space; a guide vane 4 is arranged on the first enclosure structure; the guide vane 4 causes the water body to pre-spin, and the pre-spin direction of the water body is opposite to the rotation direction of the propeller;

[0030] The first surrounding wall structure 2 includes a left surrounding wall body 2-1 and a right surrounding wall body 2-2, and an expansion angle of the left surrounding wall body 2-1 is greater than an expansion angle of the right surrounding wall body 2-2.

[0031] The first enclosure structure 2 is in an arc shape as a whole. The left enclosure body 2-1 and the right enclosure body 2-2 are based on the longitudinal center axis 5 of the tail tube. When viewed from the stern, the portion of the first enclosure structure located on the left side of the longitudinal center axis 5 of the tail tube is the left enclosure body 2-1, and the portion of the first enclosure structure located on the right side of the longitudinal center axis 5 of the tail tube is the right enclosure body 2-2. The expansion angle of the left enclosure body 2-1 refers to the center angle between the end of the left enclosure body 2-1 and the longitudinal center axis 5 of the tail tube, and the expansion angle of the right enclosure body 2-2 refers to the center angle between the end of the right enclosure body 2-2 and the longitudinal center axis 5 of the tail tube.

[0032] The propeller shaft passes through the tail tube 1 at the stern of the ship, and the propeller is installed on the propeller shaft, and the propeller is located behind the guide vane 4. When the propeller is working, the incoming flow in front of the propeller enters the wall space, and the water body is pre-swirled by the guide vane 4, and then passes through the propeller disk and flows to the rear of the ship.

[0033] After the water body passes through the pre-swirl effect of the guide vane 4, the flow state of the water body in front of the propeller is more uniform and stable, reducing the turbulence and eddy current inside the water body, providing the propeller with a more uniform, more stable and faster inflow. Moreover, since the pre-swirl direction of the water body is opposite to the rotation direction of the propeller, the relative tangential speed between the water body and the propeller can be increased, which helps the propeller to achieve a higher propulsion efficiency; while maintaining the same speed, the power required by the propeller is reduced, thereby reducing energy consumption.

[0034] The second enclosure structure serves as a connecting member between the first enclosure structure and the stern tube 1 of the ship, ensuring the formation of the enclosure space. At the same time, the second enclosure structure can also achieve a pre-swirl effect on the water body to a certain extent, playing the same role as the guide vane 4.

[0035] Among them, the expansion angle of the right surrounding wall body 2-2 is 0° to 60°, and the expansion angle of the left surrounding wall body 2-1 is 90° to 120°.

[0036] In the present invention, the expansion angle of the left side surrounding wall 2-1 is greater than the expansion angle of the right side surrounding wall 2-2, that is, the arc length of the left side surrounding wall 2-1 is greater than the arc length of the right side surrounding wall 2-2, so that the left side surrounding wall 2-1 has a larger flow area than the right side surrounding wall 2-2.

[0037] join Figure 5 and Figure 6 , Figure 5 This is the velocity cloud diagram of the water flow along the propeller circumference when the front pre-rotation guide wheel is not set. Figure 6 This is the velocity cloud diagram of the water flow along the propeller circumference at the propeller disk after the pre-rotation guide wheel is set. Figure 5 and Figure 6 The blue area represents the direction of rotation of the water body and the propeller, and the red area represents the direction of rotation of the water body and the propeller. Figure 5 It can be seen that when the front pre-rotation guide wheel is not set, about half of the water in the area in front of the propeller has a rotation direction that is consistent with the rotation direction of the propeller, which results in a small relative tangential speed between the water and the propeller, resulting in a low propeller propulsion efficiency; after the front pre-rotation guide wheel is set, the water in the surrounding wall space in front of the propeller has a tangential speed opposite to the rotation direction of the propeller, thereby increasing the relative tangential speed between the water and the propeller, and further improving the propeller propulsion efficiency.

[0038] The second wall structures 3 at both ends of the first wall structure 2 are airfoil structures with a twist angle, the second wall structure 3 is connected to the first wall structure 2, one end of the second wall structure is connected to the outer surface of the stern tube 1 of the ship; the twist angle of the second wall structure from one end to the other end is 0-20 degrees. In this embodiment, the end of the second wall structure 3 away from the stern tube 1 is fixedly connected to the inner side of the first wall structure 2.

[0039] The second surrounding wall structure 3 adopts an airfoil structure, one side of its cross section is straight and the other side is a convex arc. This structure has good fluid properties and can reduce the resistance of water when passing through the second surrounding wall structure. In addition, the second surrounding wall structure has a certain torsion angle, and the second surrounding wall structure is twisted around its own length direction. The setting of this torsion structure can make the second surrounding wall structure form different angles of attack at different radii. The closer the position of the second surrounding wall structure is to the tail tube 1, the smaller its angle of attack is, and the farther away from the tail tube 1, the larger its angle of attack is. The larger the angle of attack is, the greater the pre-swirl effect on the water body is. In this way, the overall efficiency of the propeller can be improved according to the distribution of the actual pitch of the propeller at different radii.

[0040] The attack angle of the second surrounding wall structure 3 is the angle between the plane where the second surrounding wall structure is located and the propeller disk.

[0041] The outer surface of the first surrounding wall structure 2 is a conical surface, and the taper range of the outer surface of the first surrounding wall structure 2 is 1:5 to 1:20. The diameter of one end of the outer surface of the first surrounding wall structure away from the propeller is larger than the diameter of the other end.

[0042] The cross-sections of the first surrounding wall structure 2 and the second surrounding wall structure 3 are airfoil structures, and the chord length of the cross-sections is between 0.8 and 2.5 times the length of the propeller hub.

[0043] The number of guide vanes 4 on the first surrounding wall structure 2 can be set according to actual needs. In this embodiment, 2-3 guide vanes 4 are arranged on the first surrounding wall structure 2, and the interval angle between two adjacent guide vanes 4 is 25° to 45°.

[0044] In this embodiment, one end of the guide vane 4 is connected to the stern tube 1 of the ship, and the other end of the guide vane 4 is fixed to the inner wall of the first surrounding wall structure 2. The torsion angle of the guide vane 4 from one end to the other end is 0° to 10°.

[0045] The guide vane 4 twists around its own length direction. The setting of this twisting structure can make the guide vane 4 form different angles of attack at different radii. The closer the guide vane 4 is to the tail tube 1, the smaller its angle of attack is, and the farther away from the tail tube 1, the larger its angle of attack is. The larger the angle of attack is, the greater the pre-swirl effect on the water body is. In this way, the overall efficiency of the propeller can be improved according to the distribution of the actual pitch of the propeller at different radii.

[0046] The attack angle of the guide vane 4 is the angle between the plane where the second surrounding wall structure is located and the propeller disk.

[0047] like Figure 4 As shown, the cross section of the guide vane 4 is an airfoil structure, the distance between the highest bulge position of its arc side and the front end of the guide vane 4 is L1, the chord length of the cross section of the guide vane 4 is L, and the length of L1 is 0.1-0.3 times the length of L.

[0048] Embodiment 2:

[0049] like Figure 7 As shown, the difference between Example 2 and Example 1 is that one end of the guide vane 4 is connected to the stern tube 1 of the ship, the other end of the guide vane 4 is higher than the outer side of the first surrounding wall structure, and the guide vane 4 is partially located in the surrounding wall space.

[0050] Furthermore, a transition connection structure 6 is provided between the guide vane 4 and the outer side of the first surrounding wall structure. The transition connection structure 6 can make a smooth transition between the portion of the guide vane 4 that is higher than the outer side of the first surrounding wall structure and the outer side surface of the first surrounding wall structure, thereby improving the connection strength between the guide vane 4 and the first surrounding wall structure and reducing the resistance of the water body when passing through this position.

[0051] In addition, one end of the second surrounding wall structure away from the tail tube 1 is also higher than the outer side of the first surrounding wall structure, and a transition connection structure 6 is provided between the second surrounding wall structure and the outer side of the first surrounding wall structure. The transition connection structure 6 can make a smooth transition between the part of the second surrounding wall structure that is higher than the outer side of the first surrounding wall structure and the outer side surface of the first surrounding wall structure.

[0052] The rest of the structure of Example 2 is the same as that of Example 1.

[0053] The present invention is not limited to the above-mentioned optimal implementation mode. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that are the same or similar to those of the present application fall within the protection scope of the present invention.

Claims

1. A front pre-rotation guide wheel, characterized in that: It comprises a first enclosure wall structure arranged at the stern of the ship, a second enclosure wall structure is respectively arranged between the two ends of the first enclosure wall structure and the stern tube, and the first enclosure wall structure, the second enclosure wall structure and the stern tube of the ship are jointly enclosed to form an enclosure wall space; the first enclosure wall structure is provided with a guide vane; The first surrounding wall structure includes a left surrounding wall body and a right surrounding wall body, and an expansion angle of the left surrounding wall body is greater than an expansion angle of the right surrounding wall body.

2. A pre-rotation guide wheel according to claim 1, characterized in that: The expansion angle of the right side surrounding wall body is 0-60°, and the expansion angle of the left side surrounding wall body is 90°-120°.

3. A pre-rotation guide wheel according to claim 1, characterized in that: The second surrounding wall structure is an airfoil structure with a twist angle. The second surrounding wall structure is connected to the first surrounding wall structure. One end of the second surrounding wall structure is connected to the outer surface of the stern tube of the ship. The twist angle of the second surrounding wall structure from one end to the other end is 0-20 degrees.

4. A pre-rotation guide wheel according to claim 1, characterized in that: The outer surface of the first surrounding wall structure is a conical surface, and the taper range of the outer surface of the first surrounding wall structure is 1:5 to 1:

20.

5. The front pre-spin guide wheel according to claim 1, characterized in that: The cross-sections of the first surrounding wall structure and the second surrounding wall structure are airfoil structures, and the chord length of the cross-sections is between 0.8 and 2.5 times the length of the propeller hub.

6. The front pre-spin guide wheel according to claim 1, characterized in that: The first surrounding wall structure is provided with 2-3 guide vanes, and the interval angle between two adjacent guide vanes is 25° to 45°.

7. The front pre-spin guide wheel according to claim 1, characterized in that: One end of the guide vane is connected to the stern tube of the ship, and the other end of the guide vane is fixed to the inner wall of the first surrounding wall structure. The torsion angle of the guide vane from one end to the other end is 0° to 10°.

8. The front pre-spin guide wheel according to claim 1, characterized in that: One end of the guide vane is connected to the stern tube of the ship, the other end of the guide vane is higher than the outer side of the first surrounding wall structure, and the guide vane part is located in the surrounding wall space.

9. A pre-rotation guide wheel according to claim 8, characterized in that: A transition connection structure is provided between the guide vane and the outer side of the first surrounding wall structure.

Images