Axial-thrust-free propeller anti-siltation device for sediment-laden waterways

Abstract

The present invention discloses a device for preventing sediment deposition of a shaftless thruster based on a sediment-laden waterway, which includes a filtering mechanism, a sediment discharge mechanism composed of three layers of discharge mechanisms, and a high-pressure water flushing mechanism. The filtering mechanism includes conical holes and grid filters arranged in groups. The first layer of the discharge mechanism is arranged on the outer edge of the first fixing ring and the epoxy resin layer of the stator assembly. The second layer of the discharge mechanism is arranged at one end of the second fixing ring. The third layer of the discharge mechanism is arranged at one end of the outer wall of the catheter hollow shell. The present invention accelerates the flow velocity of the filtered water, improves the filtering efficiency and the discharge efficiency, improves the cooling effect inside the shaftless thruster motor, can also prevent the outside sediment-laden water from flowing back into the catheter, reduces the energy loss and structural wear of the shaftless thruster in the sediment-laden waterway, and improves the operation efficiency and operation reliability of the shaftless thruster.

Description

Technical Field

[0001] The present invention relates to a shaftless thruster, in particular to a device that enables the shaftless thruster to operate normally in a multi-sediment waterway, belonging to the technical field of ship engineering. Background Art

[0002] The shaftless rim electric thruster (hereinafter referred to as the shaftless thruster), as a new type of ship propulsion type, has the advantages of compact structure, low construction difficulty, high propulsion efficiency, low vibration, low noise, and less space occupation. It is being continuously promoted and applied in the field of military and civilian ship thrusters. As Figure 1 and Figure 2 shown, the shaftless thruster is suspended under the stern of the ship through a boom 100, and includes a duct 10, a stator assembly 20, a permanent magnet rotor 30, and several blades 40. The duct 10 is a double-layer shell in a tubular shape, and both ends are closed by covers 101. The stator assembly 20 includes an iron core 201 and a coil 202. The annular stator assembly 20 and the permanent magnet rotor 30 are respectively coated and sealed by a stator assembly epoxy resin layer 203 and a permanent magnet rotor epoxy resin layer 301. The stator assembly 20 is fixed in the duct 10. The permanent magnet rotor 20 is installed in the inner hole of the stator assembly 10, and the gap between the two is 4-5 mm. Both ends of the permanent magnet rotor 30 are respectively supported in the inner ends of both ends of the duct 10 through thrust bearings 50. One end of the 4 blades 40 is evenly fixed on the middle part of the inner hole of the permanent magnet rotor 30. After being energized, the coil 202 of the stator assembly 20 induces a rotating magnetic field, causing the permanent magnet rotor 30 to generate a torque, thereby driving the permanent magnet rotor 30 to drive the blades 40 to rotate, generating the power for the ship to sail.

[0003] Due to the compact internal structure layout of the shaftless thruster, especially the radial gap between the stator assembly 20 and the permanent magnet rotor 30, and the axial and radial gaps between the moving ring 501 and the static ring 502 of the thrust bearing 50 are very small. When the ship sails in a multi-sediment waterway, it enters between the stator assembly 20 and the permanent magnet rotor 30, as well as between the moving ring 501 and the static ring 502 of the thrust bearing 50. The water flow flowing into the shaftless thruster deposits sediment therein due to the reduced flow velocity, increasing the resistance torque of the permanent magnet rotor 30, thereby increasing the operating resistance of the shaftless thruster, increasing the power consumption, and thus reducing its endurance mileage. In addition, due to the multi-sediment slowing down the flow velocity of the sediment-laden water coolant in the shaftless thruster, the heat inside the shaftless thruster cannot be efficiently dissipated, which has a great impact on the operating efficiency of the shaftless thruster and thus affects its overall performance. Summary of the Invention

[0004] The object of the present invention is to provide a sediment deposition prevention device for a shaftless thruster based on a multi-sediment waterway, which reduces excessive sediment deposition in the areas near the axial and radial gaps inside the shaftless thruster during operation, improves the operation efficiency of the shaftless thruster in a multi-sediment environment, and enhances its overall adaptability and operation level.

[0005] The object of the present invention can be achieved by the following technical solutions:

[0006] A sediment deposition prevention device for a shaftless thruster based on a multi-sediment waterway, comprising a filtering mechanism arranged at both ends of the inner wall of the duct housing, a sediment discharge mechanism arranged inside the duct, and a high-pressure water scouring mechanism arranged inside and outside the stern of the ship and inside the duct. The filtering mechanism includes a set of frustum-shaped holes and a grid filter screen. The frustum-shaped holes are uniformly distributed on both ends of the inner wall of the duct housing with the outer part being large and the inner part being small, and the grid filter screen is fixed in the frustum-shaped holes; the large end diameter of the frustum-shaped hole is 60 - 90 mm, and the small end diameter is 50 mm; the grid filter screen includes two layers of grid bars that are fixedly connected vertically and horizontally, and the aperture of the grid mesh is less than 5 mm × 5 mm;

[0007] The sediment discharge mechanism includes a first-layer discharge mechanism, a second-layer discharge mechanism, and a third-layer discharge mechanism arranged in sequence from the inner wall of the duct housing towards the outer wall of the duct housing. The first-layer discharge mechanism is arranged on the first fixing ring and the outer edge of the epoxy resin layer of the stator assembly. Both ends of the first fixing ring are respectively fixed on the static ring support ring and the outer support ring, and the middle part of the first fixing ring covers the outer peripheral surface of the epoxy resin layer of the stator assembly; the second-layer discharge mechanism is arranged on one end of the second fixing ring. Both ends of the second fixing ring are respectively fixed on the middle part of the outer support ring, and the outer peripheral surface of the outer support ring is respectively fixed inside the port of the outer wall of the duct housing; the third-layer discharge mechanism is arranged on one end of the outer wall of the duct housing and corresponds to the position of the second-layer discharge mechanism;

[0008] The high-pressure water scouring mechanism is arranged on the stern cabin, the stern deck, and the second fixing ring.

[0009] The object of the present invention can also be further achieved by the following technical measures.

[0010] Furthermore, the first-layer discharge mechanism is arranged in a 120° fan-shaped manner on the radial upper and lower sides of the catheter, with the catheter axis as the symmetry axis, in the middle of the catheter cavity, and includes two groups of components that are symmetrical in the upper and lower directions. Each group of components includes multiple axial grooves and multiple asymmetric hourglass holes arranged on a first fixed ring made of stainless steel. The multiple axial grooves are also radially distributed in a 120° fan-shaped manner on the upper and lower sides of the outer edge of the epoxy resin layer of the stator assembly. The cross-sectional area of the axial grooves is 2-3 times the area of the grid mesh; the multiple asymmetric hourglass holes arranged axially at intervals along the first fixed ring correspond to the corresponding axial groove positions respectively; the third-layer discharge mechanism is arranged on one end of the outer wall of the catheter shell, and corresponds to the position of the second-layer discharge mechanism on one end of the second fixed ring.

[0011] Furthermore, the depths of the two hourglass frustum-shaped holes of the asymmetric hourglass hole are different, the ratio of the depth T1 of the first hourglass frustum-shaped hole facing the axial groove to the depth T of the asymmetric hourglass hole is: T1 / T=1 / 3, the cone angle α of the first hourglass frustum-shaped hole is greater than the second hourglass cone angle β away from the axial groove, the connected hole diameter D of the two hourglass frustum-shaped holes is 5-6 mm, and the hole spacing A of the spaced asymmetric hourglass holes is 20-40 mm.

[0012] Furthermore, the second-layer discharge mechanism includes a plurality of arc-shaped sediment flushing grooves and a plurality of second-layer drainage holes on a second stainless steel fixed ring. The arc-shaped sediment flushing grooves are radially concave away from the axis of the second fixed ring and are evenly distributed on one end of the second fixed ring. The radius R of the arc-shaped sediment flushing grooves is greater than 30 mm. The second-layer drainage holes are axially spaced in a group of two at the other end of the second fixed ring, and multiple groups of second-layer drainage holes are radially evenly arranged on the other end of the second fixed ring.

[0013] Furthermore, the second layer of drainage holes is an oblong hole, the longitudinal direction of the oblong hole is parallel to the axis of the second fixing ring, the longitudinal center section of the oblong hole is a parallelogram, and the inclined direction of the parallelogram is toward one end of the conduit; the inclined end of the bent fish-scale baffle is fixed on one end of the oblong hole, the inclined direction of the inclined end is consistent with the inclined direction of the parallelogram, the horizontal end of the fish-scale baffle is located on the upper side of the oblong hole and parallel to the oblong hole, and the oblong hole and the fish-scale baffle are evenly distributed along the radial end of the conduit; the third layer of discharge mechanism corresponds to the position of the second layer of discharge mechanism, and one end of the high-pressure water flushing mechanism is respectively arranged in one end of the arc-shaped mud and sand flushing groove.

[0014] Furthermore, the distance B between the lower side of the horizontal end of the fish-scale baffle and the upper side of the second fixing ring is ≤5mm, the thickness C of the fish-scale baffle is not less than 1 / 5 of the thickness E of the second fixing ring, the axial distance F of the two second-layer drainage holes is 15-25mm, and the axial distance G of the two third-layer drainage holes is 90-110mm; the fish-scale baffle, the second-layer drainage holes and the third-layer drainage holes are all plated with an anti-corrosion metal layer.

[0015] Further, the third-layer discharge mechanism includes a plurality of third-layer drain holes, which are horizontally arranged oblong holes. Two horizontally arranged oblong holes arranged side by side are axially spaced in a group, and multiple groups of third-layer drain holes are evenly arranged on the other radial end of the outer wall of the conduit housing, and the positions of the third-layer drain holes correspond to those of the second-layer drain holes; the axes of the third-layer drain holes are perpendicular to the axes of the second-layer drain holes, and the horizontal central section of the third-layer drain holes is also a parallelogram, and the inclination directions of the parallelograms of the two third-layer drain holes are opposite.

[0016] Further, the high-pressure water scouring mechanism includes a water storage tank, a motor, a water pump, a high-pressure water sprayer, a water inlet pipe and a water outlet pipe. The water storage tank is fixed on the stern deck, and the motor and the water pump connected to each other through a coupling are fixed in the stern cabin; both ends of the water inlet pipe are respectively connected to the water storage tank and the input end of the water pump, one end of the water outlet pipe is connected to the output end of the water pump, and the other end of the water outlet pipe extends into the conduit and then winds around the conduit, and is respectively fixed on the middle part of the static ring support ring of the thrust bearing through a plurality of evenly distributed support blocks; a plurality of evenly distributed axial branch pipes are respectively connected to the input ends of the high-pressure water sprayers, and the middle parts of the high-pressure water sprayers are respectively fixed in one ends of the corresponding arc-shaped sediment scouring grooves through support plates.

[0017] Further, the support ring is fixed between the outer wall of the conduit housing and the outer circle of the second fixing ring, and is located at a position close to the second-layer discharge mechanism and the third-layer discharge mechanism.

[0018] The filtering mechanism of the present invention adopts a frustum-shaped hole and a grid bar structure fixedly connected in two layers vertically and horizontally, filters out sediment particles with a diameter greater than 5 mm, accelerates the flow rate of the filtered water, minimizes the possibility of sediment particles getting stuck in the filter holes and reduces the maintenance difficulty, and improves the filtering efficiency and economy. The multiple axial channels and multiple asymmetric hourglass holes of the first-layer discharge mechanism, the multiple oblong holes with fish-scale-shaped baffles, the multiple arc-shaped sediment scouring grooves of the second-layer discharge mechanism and the multiple horizontally arranged oblong holes of the third-layer discharge mechanism, as well as the scouring effect of the high-pressure water scouring mechanism on the sediment, can greatly increase the flow rate and discharge efficiency of the sediment water, improve the cooling effect inside the motor of the shaftless thruster, prevent the outside sediment water from flowing back into the conduit, avoid large-particle sediment deposition and blockage in the shaftless thruster motor, reduce the energy loss and structural wear of the shaftless thruster in a multi-sediment waterway, and improve the operation efficiency and reliability of the shaftless thruster.

[0019] The advantages and features of the present invention will be illustrated and explained through the non-restrictive description of the following preferred embodiments, which are given only as examples with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a structural schematic diagram of the present invention;

[0021] Figure 2 is Figure 1 the reduced sectional view taken along line A-A;

[0022] Figure 3 is Figure 1 the enlarged view of part I of

[0023] Figure 4 is Figure 3 the enlarged view of part II of

[0024] Figure 5 is Figure 3 the enlarged view of part III of

[0025] Figure 6 is Figure 1 the enlarged view of part IV of

[0026] Figure 7 is the structural schematic diagram of the high-pressure water scouring mechanism;

[0027] Figure 8 is Figure 1 the reduced sectional view taken along line B-B. Specific Embodiments

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0029] In the description of the present invention, terms indicating directions or positions such as "upper", "lower", "inner", "outer", "left", "right", etc. are based on the directions shown in the accompanying drawings, and are only for simplifying the description, rather than indicating or implying that the present invention must have a specific direction or position.

[0030] As Figures 1 to 4 shown, this embodiment includes a filtering mechanism 1 provided at both ends of the inner wall 102 of the conduit housing, a sediment discharge mechanism 2 provided in the conduit 10, and a high-pressure water scouring mechanism 5 provided inside and outside the stern of the ship and in the conduit 10. As Figure 4 shown, the filtering mechanism 1 includes a group of frustum-shaped holes 11 and a grid filter 12. The frustum-shaped holes 11 are uniformly distributed at both ends of the inner wall 102 of the conduit housing with the outer large and the inner small, and the grid filter 12 is fixed in the frustum-shaped holes 11. The large end diameter of the frustum-shaped hole 11 is 60 - 90 mm, and the small end diameter is 50 mm. The grid filter 12 includes two inner and outer layers of grid bars 121 that are fixedly connected in a vertical and horizontal intersection, and the grid aperture is less than 5 mm × 5 mm; the structure combining the frustum-shaped hole 11 and the grid filter 12 filters sediment particles with a diameter greater than or equal to 5 mm, provides good filtering performance, improves the water flow velocity inside the shaftless thruster to a certain extent, accelerates the heat exchange inside the shaftless thruster, and better ensures the operating performance of the shaftless thruster.

[0031] The sediment discharge mechanism 2 includes a first-layer discharge mechanism 21, a second-layer discharge mechanism 22, and a third-layer discharge mechanism 23 arranged in sequence from the inner wall 102 of the conduit housing to the outer wall 103 of the conduit housing. The first-layer discharge mechanism 21 is arranged on the first fixing ring 3 and the outer edge of the stator assembly epoxy resin layer 203. The two ends of the first fixing ring 3 are respectively fixed between the stationary ring support ring 60 and the outer support ring 70, and the middle part of the first fixing ring 3 is covered on the outer peripheral surface of the stator assembly epoxy resin layer 203. The second-layer discharge mechanism 22 is arranged on the right end of the second fixing ring 4. The two ends of the second fixing ring 4 are respectively fixed on the middle part of the outer support ring 70, and the outer peripheral surface of the outer support ring 70 is respectively fixed inside the port of the outer wall 103 of the conduit housing; the third-layer discharge mechanism 23 is arranged on the right end of the outer wall 103 of the conduit housing and corresponds to the position of the second-layer discharge mechanism 22.

[0032] As Figure 3 and Figure 5 shown, the first-layer discharge mechanism 21 is on the upper and lower sides in the radial direction of the conduit 10 and is arranged in a 120° fan shape up and down with the axis of the conduit 10 as the axis of symmetry in the middle of the conduit cavity. It includes two groups of symmetrically arranged components. Each group of components includes multiple axial channels 211 and multiple asymmetric hourglass holes 32 arranged on the first fixing ring 3 made of stainless steel. 13 axial channels 211 are also radially evenly distributed in a 120° fan shape on the upper and lower sides of the outer edge of the stator assembly epoxy resin layer 203. The cross-sectional area of the axial channels 211 is 2-3 times that of the grid mesh area, which facilitates the rapid passage of the water flow entering the shaftless thruster and improves the cooling effect of the shaftless thruster. Multiple asymmetric hourglass holes 32 arranged at intervals along the axis of the first fixing ring 3 correspond to the positions of the corresponding axial channels 211 respectively. As Figure 3 and Figure 5 shown, the depths of the two hourglass frustum-shaped holes of the asymmetric hourglass hole 32 are not equal. The ratio of the depth T1 of the first hourglass frustum-shaped hole facing the axial channel 211 to the depth T of the asymmetric hourglass hole is: T1 / T = 1 / 3. The conical angle α of the first hourglass frustum-shaped hole is greater than the second hourglass conical angle hole β facing away from the axial channel. In this embodiment, α = 150° and β = 135°. The aperture D of the connecting hole of the two hourglass frustum-shaped holes is 5-6 mm, and the hole pitch A of the asymmetric hourglass holes 32 arranged at intervals is 20-40 mm. Such a structure enables the small-particle sediment mixture in the water to quickly flow to the second-layer discharge mechanism 22.

[0033] As Figure 2 、 Figure 3 and Figure 6As shown, the second-layer drainage mechanism 22 is disposed on one end of the second fixing ring 4. The two ends of the second fixing ring 4 are respectively fixed to the middle portion of the outer support ring 70, the outer circumference of which is respectively fixed within the port of the outer wall 103 of the catheter housing. The second stainless steel fixing ring 4 comprises multiple arcuate sediment flushing grooves 41 and multiple second-layer drainage holes 42. The arcuate sediment flushing grooves 41 are radially concave away from the axis of the second fixing ring 4 and are evenly distributed on the left end of the second fixing ring 4. The radius R of the arcuate sediment flushing grooves 41 is greater than 30 mm. The second-layer drainage holes 42 are arranged in groups of two axially spaced apart on the right end of the second fixing ring 4, and multiple groups of second-layer drainage holes 42 are evenly distributed radially on the right end of the second fixing ring 4. The support ring 80 is fixed between the outer wall 103 of the catheter housing and the outer circumference of the second fixing ring 4, and is located near the second-layer drainage mechanism 22 and the third-layer drainage mechanism 23, thereby enhancing the support strength of the second fixing ring 4.

[0034] The second-layer drainage holes 42 are oblong holes, the longitudinal direction of which is parallel to the axis of the second fixing ring 4. The longitudinal center cross-section of the oblong holes is a parallelogram, and the inclination direction of the parallelogram is toward the right end of the conduit 10. The inclined end 431 of the bent fish-scale baffle 43 is fixed to the left end of the oblong hole, and the inclination direction of the inclined end is consistent with the inclination direction of the parallelogram. The horizontal end 432 of the fish-scale baffle 43 is located above the oblong hole and parallel to the oblong hole. The oblong hole and the fish-scale baffle 43 are evenly distributed along the radial right end of the conduit 10. The distance B between the lower side of the horizontal end 432 of the fish-scale baffle 43 and the upper side of the second fixing ring 4 is ≤5mm. The thickness C of the fish-scale baffle is not less than 1 / 5 of the thickness E of the second fixing ring. The axial distance F between the two second-layer drainage holes is 15-25mm.

[0035] The third-layer drainage mechanism 23 includes multiple third-layer drainage holes 231. These third-layer drainage holes are transversely arranged in groups of two, spaced axially apart. The multiple groups of third-layer drainage holes 231 are evenly spaced along the radially right end of the outer wall 103 of the conduit housing, corresponding to the second-layer drainage holes 42. The axes of the third-layer drainage holes 231 are perpendicular to the axes of the second-layer drainage holes 42. The transverse center cross-section of the third-layer drainage holes 231 also forms a parallelogram, with the two parallelograms of the third-layer drainage holes 231 tilted in opposite directions. The axial distance G between the two third-layer drainage holes is 90-110 mm. The fish-scale baffles 43, the second-layer drainage holes 42, and the third-layer drainage holes 231 are all coated with a corrosion-resistant metal layer. The fish-scale baffles 43 prevent sediment and water from outside the shaftless propeller from flowing back into the conduit 10.

[0036] like Figure 3 、 Figure 7 and Figure 8As shown in the figure, the high-pressure water flushing mechanism 5 is arranged on the stern cabin 201, the stern deck 202 and the second fixing ring 4, and includes a water storage tank 51, a motor 52, a water pump 53, a high-pressure water sprayer 54, a water inlet pipe 55 and a water outlet pipe 56. The water storage tank 51 is fixed on the stern deck 202, and the motor 52 and the water pump 53 connected to each other through a coupling 57 are fixed in the stern cabin 201. Both ends of the water inlet pipe 55 are respectively connected to the water storage tank 51 and the input end of the water pump 53, one end of the water outlet pipe 56 is connected to the output end of the water pump 53, and the other end of the water outlet pipe 56 extends into the conduit 10 and then winds around the conduit 10 for one circle, and is respectively fixed on the middle part of the stationary ring support ring 60 of the thrust bearing 50 through a plurality of uniformly distributed support blocks 58. A plurality of uniformly distributed axial branch pipes 561 are respectively connected to the input ends of the high-pressure water sprayers 54, and the middle parts of the high-pressure water sprayers 54 are respectively fixed on the left ends of the corresponding arc-shaped sediment flushing grooves 41 through support plates 541.

[0037] The working process of the present invention is as follows: When the shaftless thruster operates in a multi-sediment waterway, the structure in which the tapered holes 11 at both ends of the inner wall 102 of the conduit housing are combined with the grid filter 12 filters sediment particles with a diameter greater than or equal to 5 mm. The filtered water flows into the shaftless thruster in the direction indicated by the arrows in Figure 1 and Figure 3 and quickly cools the thrust bearing 50 through the gap flow path between the moving ring 501 and the stationary ring 502 of the thrust bearing 50. Then the water flow first passes through the plurality of axial channels 211 and the plurality of asymmetric hourglass holes 32 of the first-layer discharge mechanism 21 in sequence, and then passes through the second-layer drain holes 42 of the second-layer discharge mechanism 22 and the third-layer drain holes 231 of the third-layer discharge mechanism 23 in sequence. At the same time, the high-pressure water sprayed by the high-pressure water sprayer 54 respectively flushes into the corresponding arc-shaped sediment flushing grooves 41 to wash the sediment, and finally is discharged at high speed into the external water area. The three-stage discharge of the filtered water is completed.

[0038] This embodiment can enable technicians in the field to understand the present invention more comprehensively, but does not limit the present invention to the scope of the described embodiments. In addition to the above embodiments, the present invention can also have other implementation manners. Any technical solutions formed by equivalent replacement or equivalent transformation fall within the protection scope of the present invention.

Claims

1. An anti-sedimentation device for a shaftless thruster based on a multi-sediment channel, characterized in that: It includes a filtering mechanism arranged at both ends of the inner wall of the duct housing, a sediment discharging mechanism arranged in the duct, and a high-pressure water flushing mechanism arranged inside and outside the stern of the ship and in the duct. The filtering mechanism includes a set of frustum-shaped holes and a grid filter screen. The frustum-shaped holes are uniformly distributed at both ends of the inner wall of the duct housing with the outer part larger and the inner part smaller. The grid filter screen is fixed in the frustum-shaped holes. The large end diameter of the frustum-shaped hole is 60 - 90 mm, and the small end diameter is 50 mm. The grid filter screen includes two inner and outer layers of grid bars fixedly connected vertically and horizontally, and the aperture of the grid mesh is less than 5 mm × 5 mm. The sediment discharging mechanism includes a first-layer discharging mechanism, a second-layer discharging mechanism, and a third-layer discharging mechanism arranged in sequence from the inner wall of the duct housing towards the outer wall of the duct housing. The first-layer discharging mechanism is arranged on the first fixing ring and the outer edge of the epoxy resin layer of the stator assembly. Both ends of the first fixing ring are respectively fixed between the stationary ring support ring and the outer support ring, and the middle part of the first fixing ring covers the outer peripheral surface of the epoxy resin layer of the stator assembly. The second-layer discharging mechanism is arranged on one end of the second fixing ring. Both ends of the second fixing ring are respectively fixed on the middle part of the outer support ring, and the outer peripheral surface of the outer support ring is respectively fixed inside the port of the outer wall of the duct housing. The third-layer discharging mechanism is arranged on one end of the outer wall of the duct housing and corresponds to the position of the second-layer discharging mechanism. The high-pressure water flushing mechanism is arranged on the stern cabin, the stern deck, and the second fixing ring. The high-pressure water flushing mechanism includes a water storage tank, a motor, a water pump, a high-pressure water sprayer, a water inlet pipe, and a water outlet pipe. The water storage tank is fixed on the stern deck, and the motor and the water pump connected to each other through a coupling are fixed in the stern cabin. Both ends of the water inlet pipe are respectively connected to the water storage tank and the input end of the water pump, one end of the water outlet pipe is connected to the output end of the water pump, and the other end of the water outlet pipe extends into the duct and then winds around the duct for one circle, and is respectively fixed on the middle part of the stationary ring support ring of the thrust bearing through a plurality of uniformly distributed support blocks. A plurality of uniformly distributed axial branch pipes are respectively connected to the input end of the high-pressure water sprayer, and the middle part of the high-pressure water sprayer is respectively fixed in one end of the corresponding arc-shaped sediment flushing groove through a support plate. The first-layer discharging mechanism is arranged on the upper and lower sides in the radial direction of the duct, and is arranged in a 120° sector shape in the middle of the duct cavity with the duct axis as the symmetry axis. It includes two groups of symmetrically arranged components. Each group of components includes multiple axial channels and a plurality of asymmetric hourglass holes arranged on the first fixing ring made of stainless steel. The multiple axial channels are also radially uniformly distributed in a 120° sector shape on the upper and lower sides of the outer edge of the epoxy resin layer of the stator assembly. The cross-sectional area of the axial channel is 2 - 3 times the area of the grid mesh. A plurality of asymmetric hourglass holes arranged at intervals along the axis of the first fixing ring respectively correspond to the positions of the corresponding axial channels. It is arranged on one end of the outer wall of the duct housing and corresponds to the position of the second-layer discharging mechanism on one end of the second fixing ring. The second-layer discharge mechanism includes a plurality of arc-shaped sediment flushing grooves and a plurality of second-layer drainage holes on a second stainless steel fixing ring. The arc-shaped sediment flushing grooves are radially concave away from the axis of the second fixing ring and are evenly distributed on one end of the second fixing ring. The radius of the arc-shaped sediment flushing grooves R is greater than 30 mm. The second-layer drainage holes are axially spaced in groups of two at the other end of the second fixing ring, and multiple groups of second-layer drainage holes are radially evenly distributed on the other end of the second fixing ring. The third-layer discharge mechanism includes multiple third-layer drainage holes, which are transverse oblong holes. The transverse oblong holes arranged side by side are arranged in groups of two with axial spacing. Multiple groups of third-layer drainage holes are evenly arranged on the other radial end of the outer wall of the catheter shell, and the positions of the third-layer drainage holes and the second-layer drainage holes correspond to each other; the axis of the third-layer drainage hole is perpendicular to the axis of the second-layer drainage hole, the transverse center section of the third-layer drainage hole is also a parallelogram, and the inclination directions of the two third-layer drainage hole parallelograms are opposite.

2. The anti-siltation device for the shaftless thruster based on the multi-silt waterway according to claim 1, wherein: The two hourglass frustum-shaped holes of the asymmetric hourglass hole have different depths. The ratio of the depth T1 of the first hourglass frustum-shaped hole facing the axial groove to the depth T of the asymmetric hourglass hole is: T1 / T=1 / 3. The cone angle α of the first hourglass frustum-shaped hole is greater than the cone angle β of the second hourglass hole facing away from the axial groove. The diameter D of the connected hole of the two hourglass frustum-shaped holes is 5-6 mm. The hole spacing A of the spaced asymmetric hourglass holes is 20-40 mm.

3. The anti-siltation device for a shaftless thruster based on a multi-silt channel according to claim 1, wherein: The second layer of drainage holes is an oblong hole, the longitudinal direction of the oblong hole is parallel to the axis of the second fixing ring, the longitudinal center section of the oblong hole is a parallelogram, and the inclination direction of the parallelogram is toward one end of the conduit; the inclined end of the bent fish-scale baffle is fixed on one end of the oblong hole, the inclination direction of the inclined end is consistent with the inclination direction of the parallelogram, the horizontal end of the fish-scale baffle is located on the upper side of the oblong hole and parallel to the oblong hole, and the oblong hole and the fish-scale baffle are evenly distributed along the radial end of the conduit; the third layer of discharge mechanism corresponds to the position of the second layer of discharge mechanism, and one end of the high-pressure water flushing mechanism is respectively arranged in one end of the arc-shaped sediment flushing groove.

4. The anti-siltation device for a shaftless thruster based on a multi-silt channel according to claim 3, characterized in that: The distance B between the lower side of the horizontal end of the fish-scale baffle and the upper side of the second fixing ring is ≤5mm, the thickness C of the fish-scale baffle is not less than 1 / 5 of the thickness E of the second fixing ring, the axial distance F between the two second-layer drainage holes is 15-25mm, and the axial distance G between the two third-layer drainage holes is 90-110mm; the fish-scale baffle, the second-layer drainage holes, and the third-layer drainage holes are all plated with an anti-corrosion metal layer.

5. The anti-siltation device for a shaftless thruster based on a multi-silt channel according to claim 1, characterized in that: The support ring is fixed between the outer wall of the conduit housing and the outer circle of the second fixing ring, and is located near the second-layer discharge mechanism and the third-layer discharge mechanism.

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