A water flow vortex elimination device and vortex elimination method for a water jet propulsion pump device inlet flow channel

Abstract

The present invention relates to a water flow vortex elimination device for a water jet propulsion pump device inlet flow channel and a vortex elimination method thereof, wherein a pressure pulsation sensor for measuring the pressure of the water flow in the water jet flow channel on the wall surface of the water jet flow channel is arranged on the upper wall surface of the water jet flow channel; a plurality of guide grooves are provided on the water jet flow channel from the inlet of the water jet flow channel to the lower end of the pump shaft, and the guide grooves are penetrated by hydraulically liftable guide grids, which can move along the guide grooves; the guide grids are arranged on the outer wall surface of the water jet flow channel and are also provided with a hydraulic lift; through the present invention, the guide grooves can prevent the boundary layer separation of the water flow at the inclined wall surface of the water jet flow channel, and when the inlet flow rate of the water jet propulsion pump is reduced and a large-scale vortex is likely to occur, the hydraulically liftable guide grids can improve the flow field structure in a targeted manner according to whether the vortex is formed, break up the backflow vortex, prevent the formation of the vortex inside the water jet flow channel, thereby suppressing the formation of the vortex, and can effectively improve the flow state of the water jet flow channel.

Description

Technical Field

[0001] The invention relates to a water flow vortex elimination device for a water inlet channel of a water jet propulsion pump device and a vortex elimination method thereof, and belongs to the technical field of ship engineering and water conservancy engineering. Background Art

[0002] Waterjets are a new type of specialized propulsion system that utilizes the reaction force of water ejected from a pump to propel a vessel forward. They offer numerous advantages, including high propulsion efficiency and excellent maneuverability. They are widely used in quiet military vessels, vessels requiring dynamic positioning, high-performance vessels, large, heavy-load transport vessels, and shallow-draft vessels. However, due to the wide flow path and short impeller of waterjets, the complex internal flow field easily generates vortex structures during operation. The evolution of these vortex structures can also lead to numerous problems, such as internal flow field energy loss and rotational stall, and are a key factor limiting the thrust and propulsion efficiency of waterjets.

[0003] In order to effectively suppress the generation of vortexes in the pump device, improve the thrust and propulsion efficiency of the pump device under operating conditions, and improve the safety and stability of the pump station operation. At present, there are relevant patents involving relevant measures: the authorized invention patent CN212744450U discloses a new shaft sleeve with guide strips. The shaft sleeve is arranged outside the pump shaft of the water jet propulsion pump device, and the shaft sleeve is fixed to the water inlet channel of the water jet propulsion pump device; the center line of the pump shaft coincides with the center line of the shaft sleeve, and a gap is left between the pump shaft and the shaft sleeve, and the gap is sealed with lubricating oil; the shaft sleeve is hollow cylindrical, and a number of guide strips are distributed on its outer wall, which reduces the separation of water flow, and also plays the role of vortex elimination and diversion. The water flows into the water inlet channel, flows in parallel with the guide strips along the water inlet direction, and flows out horizontally through the guide strips of the new shaft sleeve, playing the role of diversion.

[0004] Currently, there are relatively few patents addressing vortex elimination methods for waterjet propulsion pumps. Instead, there are more patents addressing improvements to the pump's shaft sleeve to improve the water inlet flow pattern. However, there are no patents addressing the addition of vortex elimination measures at the inlet of the water inlet channel to improve the flow pattern of the pump's inlet channel. Summary of the Invention

[0005] The purpose of the present invention is to address the deficiencies of the above-mentioned prior art and to provide a water flow vortex elimination device and a vortex elimination method for a water jet propulsion pump device.

[0006] The object of the present invention is achieved in this way:

[0007] A water flow vortex elimination device for a water jet propulsion pump device in an inlet flow channel comprises a water jet propulsion pump body, a water inlet flow channel, and a drive motor. One end of the water jet propulsion pump body is provided with a water inlet communicating with the water inlet flow channel, and the other end is provided with a water outlet. A pump shaft of the drive motor extends into the water jet propulsion pump body, and an impeller is fixed to one end of the pump shaft of the drive motor disposed within the water jet propulsion pump body. The device is characterized by:

[0008] A pressure pulsation sensor is provided on the upper wall of the water inlet channel for measuring the pressure of the water flow in the water inlet channel on the wall surface of the water inlet channel;

[0009] A plurality of guide grooves are provided on the water inlet flow channel from the water inlet flow channel entrance to the lower end of the pump shaft. The guide grooves are penetrated by hydraulically movable guide gratings, which can move along the guide grooves.

[0010] The guide grid bars are arranged on the outer wall of the water inlet flow channel and are further provided with a hydraulic lift, which is connected to the guide grid bars. The guide grid bars rise and fall as the hydraulic lift rises and falls, thereby the guide grid bars move along the guide groove, driving the guide grid bars to extend into the water inlet flow channel or exit from the water inlet flow channel;

[0011] A flexible water stop is provided at the connection between the guide groove and the guide grid bar on the water inlet flow channel;

[0012] A controller is also provided, which is connected to the pressure pulsation sensor and the hydraulic lift respectively. The pressure pulsation sensor transmits information on whether a vortex occurs to the controller in real time;

[0013] When the pressure pulsation sensor identifies the occurrence of a vortex, it sends a command to the hydraulic lift through the controller, controlling the hydraulic lift to drive the guide grid to rise and extend into the water inlet channel;

[0014] When the pressure pulsation sensor identifies that no vortex occurs, the controller controls the hydraulic lift to lower the guide grid bars and exit from the water inlet channel.

[0015] The specific setting method of the pressure pulsation sensor is:

[0016] From the upper wall of the water inlet channel to the lower end of the pump shaft in the water inlet channel The specific setting range is shown in the figure. Three pressure pulsation sensors are set on the water inlet flow channel section, and the pressure pulsation sensors are respectively located at -40°, 0°, and 40° to the plumb line on the section; this pressure pulsation sensor setting method is used to accurately determine whether a vortex is formed.

[0017] Assume that the diameter of the water outlet is D, along the water inlet to the lower end of the pump shaft There are several guide grooves on the water inlet channel;

[0018] The guide groove is wide high rectangular groove.

[0019] The guide grooves are arranged on the upper wall of the water inlet channel, one every 22.5°. A total of 9 guide grooves and guide bars are arranged, with 3 guide bars forming a group. Every 3 guide bars are connected to 1 hydraulic lift. There are a total of 3 hydraulic lifts to control the lifting of the guide bars.

[0020] A top plate is provided outside the water inlet flow channel, and a hydraulic lift is fixedly installed on the top plate.

[0021] A method for eliminating vortexes by a water flow vortex elimination device in a water inlet channel of a water jet propulsion pump device is characterized by comprising the following steps:

[0022] S1. Start the drive motor. The pump shaft of the drive motor rotates, driving the impeller to rotate. Water enters from the water inlet of the water inlet channel, flows into the pump body of the water jet propulsion pump through the water inlet channel, and is then sprayed out from the water spray port.

[0023] S2. The pressure pulsation sensor measures the pressure of the water flow on the water inlet channel wall. When the water flow breaks off and forms a vortex in the water inlet channel, the water flow rate decreases and the pressure on the upper wall of the water inlet channel increases. Therefore, the real-time sensing data of the pressure pulsation sensor can be used to determine whether a vortex has formed in the water inlet channel.

[0024] S3. When no vortex is formed in the water inlet channel, the guide groove has a stabilizing effect on the water flow inside the water inlet channel, which can alleviate the occurrence of boundary layer separation;

[0025] When a vortex forms in the water inlet channel, the pressure pulsation sensor sends a command to the hydraulic lift through the controller, controlling the hydraulic lift to rise, driving the guide grid bars to extend into the water inlet channel. As a result, the guide grid bars automatically rise after the pressure pulsation sensor detects the occurrence of the vortex, making the water flow velocity in the water inlet channel uniform, changing the flow field structure, disrupting the vortex structure, and greatly improving the flow pattern of the water in the water inlet channel.

[0026] When the vortex in the water inlet flow channel disappears, the pressure pulsation sensor recognizes that the pressure pulsation on the upper wall of the water inlet flow channel has decreased. The pressure pulsation sensor sends an instruction to the hydraulic lift through the controller to control the hydraulic lift to lower. At this time, the guide grid bars automatically lower to form a guide groove to stabilize the water flow inside the water inlet flow channel.

[0027] In step S3:

[0028] When the vortex in the water inlet channel occurs, the pressure pulsation sensor detects that the wall pressure rises, the guide grid rises, and the height of the guide grid in the water inlet channel is When water backflow occurs on the slope side, the guide grid bars can break up the vortex and effectively prevent the formation of vortex inside the water inlet channel, thereby inhibiting the occurrence and development of vortex and improving the operating efficiency of the water jet propulsion pump device.

[0029] The present method is advanced and scientific. It addresses the following issues: The water inlet channel is a crucial component of a waterjet propulsion system. Its function, in addition to conveying water, is to transfer the incoming flow's energy to the propulsion pump. The waterjet pump inlet, constrained by the ship's structural layout, is typically curved. Due to the slope pressure gradient, the pump inlet flow is uneven, causing boundary layer flow separation and the formation of a recirculation zone on the slope side, accompanied by a degree of vortex. This results in significant hydraulic losses within the component piping, a decrease in pump efficiency, and even instability. While installing guide bars directly within the water inlet channel can mitigate vortex formation to some extent, the inclusion of guide bars reduces the channel's cross-sectional area and increases flow velocity, increasing hydraulic losses and reducing overall pump efficiency. Existing engineering practice and testing have shown that power losses in the water inlet pipe account for approximately 7% to 9% of the main engine's total power, and its interaction with the ship's hull can impact propulsion efficiency by as much as 20%.

[0030] Through the present invention, in order to effectively alleviate the occurrence of vortices inside the water inlet channel, avoid the further evolution of the internal vortex structure affecting the energy loss of the internal flow field, seriously restrict the thrust and propulsion efficiency of the water jet propulsion pump device, and suppress the formation of vortices when the water jet propulsion pump device is more prone to vortexes under low flow conditions. Therefore, a vortex elimination and diversion device is set at the inlet and upper wall of the water inlet channel of the water jet propulsion pump device. The diversion effect of the vortex elimination device reduces the flow velocity gradient between the water flow near the wall and the central water flow, uniformizes the flow velocity of the water flow in the water inlet channel, changes the flow field structure, and alleviates the occurrence of boundary layer separation. On the other hand, the hydraulically liftable guide grating device can monitor the upper wall pressure of the water inlet channel under low flow conditions to detect whether a vortex is formed. When the water flow on the slope side flows back and a vortex is formed, the guide grating can be raised to break up the vortex structure, effectively preventing the formation of vortices inside the water inlet channel, thereby suppressing the occurrence and development of vortices and improving the operating efficiency of the water jet propulsion pump device. The specific setting method is as follows:

[0031] 1. A pressure pulsation sensor is set on the upper wall of the water inlet channel to measure the pressure of the water flow on the water inlet channel wall. When the water flow is separated and a vortex is formed in the water inlet channel, the flow rate decreases and the pressure on the upper wall of the water inlet channel increases. Therefore, the real-time sensing data of the pressure pulsation sensor can be used to determine whether a vortex is formed in the water inlet channel. The specific sensor setting method is to use the upper wall of the water inlet channel from the water inlet channel inlet to the lower end of the water inlet channel pump shaft. The specific setting range is shown in the figure. Three pressure pulsation sensors are set on the water inlet channel section. The pressure pulsation sensors are respectively located at -40°, 0° and 40° from the vertical line. This sensor setting method can accurately determine whether a vortex is formed (such as Figure 1 , Figure 2 ).

[0032] 2. To improve the flow field of the water inlet channel, alleviate the occurrence of boundary layer separation, and suppress the occurrence of vortexes inside the water inlet channel, a A guide groove is set at the bottom of the guide groove, and a hydraulically liftable guide grid is set at the bottom of the guide groove. On the one hand, the guide groove has a certain stabilizing effect on the water flow inside the water inlet channel, which can alleviate the occurrence of boundary layer separation phenomenon; on the other hand, the hydraulically liftable guide grid can automatically rise after the pressure pulsation sensor recognizes the occurrence of vortex, so that the water flow velocity in the water inlet channel is uniform, the flow field structure is changed, and the vortex structure is disturbed, which greatly improves the flow state of the water flow inside the water inlet channel. When the vortex in the water inlet channel disappears, the pressure pulsation sensor recognizes that the pressure pulsation on the upper wall of the water inlet channel is reduced. At this time, the guide grid automatically drops to form a guide groove to stabilize the water flow inside the water inlet channel. The guide groove is wide high The bottom of the guide groove is a hydraulically liftable guide grating, which is arranged on the upper wall of the water inlet channel, one every 22.5°. There are 9 guide grooves and hydraulically liftable guide gratings in total. Every three guide gratings form a group. There are three hydraulic lifts to control the lifting of the guide gratings to ensure the stable and safe operation of the device. To effectively prevent water leakage at the connection between the guide grid and the guide groove and ensure the effective operation of the hydraulic system, a flexible water stop is installed at the connection between the outer side of the pump housing and the guide grid. To ensure the stable operation of the hydraulic lifting device, a reinforced connection between the top plate and the hull is set.

[0033] 3. When the vortex in the water inlet channel occurs, the pressure pulsation sensor detects that the wall pressure rises, the guide grating rises, and the height of the guide grating in the pump is The guide fence can break up the vortex when the water flow backflows on the slope side, effectively preventing the formation of vortex inside the water inlet channel, thereby inhibiting the occurrence and development of vortex and improving the operating efficiency of the water jet propulsion pump device.

[0034] Beneficial effects: Through the present invention, its guide groove can effectively prevent the boundary layer separation of water flow on the inclined wall of the water inlet channel. When the inlet flow of the water jet propulsion pump decreases and large-scale vortexes are prone to occur, its hydraulically liftable guide grid can improve the flow field structure in a targeted manner according to whether the vortex is formed, break up the backflow vortex, and prevent the formation of vortex inside the water inlet channel, thereby inhibiting the formation of vortex, which can effectively improve the flow state of the water inlet channel, improve the operating efficiency of the pump device, and increase the thrust and propulsion efficiency of the pump device.

[0035] With the widespread application of water jet propulsion technology in high-performance ships and military vessels, the use of this vortex elimination device can effectively suppress the occurrence of vortices in the water inlet flow channel, improve the propulsion efficiency of the pump device, and ensure the safety of ship operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Schematic diagram of the vortex flow in the water inlet channel of the water jet propulsion pump numerical simulation;

[0037] Figure 2 This is a schematic diagram of the vortex flow inside the water inlet channel of the water jet propulsion pump;

[0038] Figure 3 Schematic diagram of the pressure pulsation sensor placement (elevation diagram of the pressure pulsation sensor placement);

[0039] Figure 4 Schematic diagram of the placement of the pressure pulsation sensor (cross-sectional diagram of the placement of the pressure pulsation sensor);

[0040] Figure 5 This is the front view of the vortex elimination and diversion part;

[0041] Figure 6 This is the cross-sectional view of the vortex elimination and flow guidance part;

[0042] In the figure: 1 water jet propulsion pump body, 2 water inlet channel, 3 drive motor, 4 water nozzle, 5 pressure pulsation sensor, 6 guide groove, 7 guide grid, 8 hydraulic lift, 9 upper wall, 10 vortex, 11 pump shaft, 12 flexible water stop, 13 top plate. DETAILED DESCRIPTION

[0043] The present invention will be further described below with reference to specific embodiments.

[0044] A water jet pump device for eliminating vortexes in a water inlet channel comprises a water jet pump body, a water inlet channel 2, and a drive motor 3. One end of the water jet pump body 1 is provided with a water inlet that penetrates the water inlet channel 2, and the other end is provided with a water outlet 4. A pump shaft 11 of the drive motor 3 extends into the water jet pump body 1, and an impeller is fixed to one end of the pump shaft 11 of the drive motor 3 disposed within the water jet pump body 1. A pressure pulsation sensor 5 is provided on the upper wall surface of the water inlet channel 2 for measuring the pressure of the water flow in the water inlet channel 2 on the wall surface of the water inlet channel 2.

[0045] A plurality of guide grooves 6 are provided on the water inlet channel 2 from the inlet of the water inlet channel 2 to the lower end of the pump shaft. The guide grooves 6 are penetrated by hydraulically movable guide gratings 7, which can move along the guide grooves 6.

[0046] The guide bars 7 are arranged on the outer wall of the water inlet channel 2, and are further provided with a hydraulic lift 8, which is connected to the guide bars 7. The guide bars 7 rise and fall as the hydraulic lift 8 rises and falls, thereby moving the guide bars 7 along the guide groove 6, driving the guide bars 7 to extend into the water inlet channel 2 or exit from the water inlet channel 2;

[0047] A flexible water stop 12 is provided at the connection between the guide groove 6 and the guide grid bar 7 on the water inlet channel 2;

[0048] A controller is also provided, which is connected to the pressure pulsation sensor 5 and the hydraulic lift 8 respectively, and the pressure pulsation sensor 5 transmits information on whether a vortex occurs to the controller in real time;

[0049] When the pressure pulsation sensor 5 detects the occurrence of a vortex, the pressure pulsation sensor 5 sends a command to the hydraulic lift 8 through the controller, controlling the hydraulic lift 8 to drive the guide grid 7 to rise and extend into the water inlet channel 2;

[0050] When the pressure pulsation sensor 5 identifies that no vortex occurs, the controller controls the hydraulic lift 8 to lower the guide grid bars 7 and withdraw them from the water inlet channel 2.

[0051] Furthermore, the specific configuration of the pressure pulsation sensor 5 is as follows:

[0052] From the upper wall of the water inlet channel 2 to the lower end of the pump shaft in the water inlet channel 2 The specific setting range is shown in the figure. Three pressure pulsation sensors 5 are set on the cross section of the water inlet channel 2, and the pressure pulsation sensors 5 are respectively located at -40°, 0°, and 40° to the plumb line on the cross section; the arrangement of the pressure pulsation sensors 5 is used to accurately determine whether a vortex is formed.

[0053] Assume that the diameter of the water outlet 4 is D, along the inlet of the water inlet channel 2 to the lower end of the pump shaft A plurality of guide grooves 6 are provided on the water inlet channel 2;

[0054] The guide groove is wide high rectangular groove.

[0055] Furthermore, the guide groove 6 is arranged on the upper wall of the water inlet channel 2, one is arranged every 22.5°, and a total of 9 guide grooves 6 and guide bars 7 are arranged, with every 3 guide bars 7 forming a group, and every 3 guide bars 7 are connected to 1 hydraulic lift 8. There are a total of 3 hydraulic lifts 8 to control the lifting and lowering of the guide bars 7.

[0056] Furthermore, a top plate 13 is provided outside the water inlet channel 2 , and the hydraulic lift 8 is fixedly installed on the top plate 13 .

[0057] A method for eliminating vortexes by a water flow vortex elimination device in a water inlet channel of a water jet propulsion pump device comprises the following steps:

[0058] S1. Start the drive motor 3. The pump shaft of the drive motor 3 rotates, driving the impeller to rotate. Water enters from the water inlet of the water inlet channel 2, flows into the water jet propulsion pump body 1 through the water inlet channel 2, and is then ejected from the water outlet 4.

[0059] S2. The pressure pulsation sensor 5 measures the pressure of the water flow in the water inlet channel 2 on the wall surface of the water inlet channel 2. When the water flow is separated and a vortex is formed in the water inlet channel 2, the water flow velocity decreases and the pressure on the upper wall surface of the water inlet channel 2 increases. Therefore, the real-time sensing data of the pressure pulsation sensor 5 can be used to determine whether a vortex has formed in the water inlet channel 2.

[0060] S3. When no vortex is formed in the water inlet channel 2, the guide groove 6 has a stabilizing effect on the water flow in the water inlet channel 2, which can alleviate the occurrence of boundary layer separation;

[0061] When a vortex forms in the water inlet channel 2, the pressure pulsation sensor 5 sends a command to the hydraulic lift 8 through the controller, controlling the hydraulic lift 8 to rise, driving the guide bars 7 to extend into the water inlet channel 2. As a result, the guide bars 7 automatically rise after the pressure pulsation sensor 5 detects the occurrence of a vortex, making the flow velocity of the water in the water inlet channel 2 uniform, changing the flow field structure, disrupting the vortex structure, and greatly improving the flow state of the water in the water inlet channel 2.

[0062] When the vortex in the water inlet channel disappears, the pressure pulsation sensor 5 recognizes that the pressure pulsation on the upper wall of the water inlet channel 2 is reduced. The pressure pulsation sensor 5 sends an instruction to the hydraulic lift 8 through the controller to control the hydraulic lift 8 to descend. At this time, the guide grid 7 automatically descends to form a guide groove 6 to stabilize the water flow inside the water inlet channel 2.

[0063] In step S3: When a vortex occurs in the water inlet channel 2, the pressure pulsation sensor 5 detects that the wall pressure rises, and the guide grating 7 rises. The height of the guide grating 7 in the water inlet channel 2 is When water flow backflows on the slope side, the guide grid bars 7 can break up the vortex, effectively preventing the formation of vortex inside the water inlet channel 2, thereby inhibiting the occurrence and development of vortex and improving the operating efficiency of the water jet propulsion pump device.

[0064] The present invention provides a water flow vortex elimination device for the water inlet channel of a water jet propulsion pump device. Its guide groove can effectively prevent the water flow from boundary layer separation on the inclined wall surface of the water inlet channel. When the inlet flow rate of the water jet propulsion pump decreases and a large-scale vortex is prone to occur, its hydraulically liftable guide grid can improve the flow field structure in a targeted manner according to whether a vortex is formed, break up the backflow vortex, and prevent the formation of vortices inside the water inlet channel, thereby suppressing the formation of vortices. It can effectively improve the flow state of the water inlet channel, improve the operating efficiency of the pump device, and increase the thrust and propulsion efficiency of the pump device. The main implementation steps are as follows:

[0065] (1) A pressure pulsation sensor is set on the upper wall of the water inlet channel to measure the pressure of the water flow on the water inlet channel wall. When the water flow is separated from the water inlet channel and a vortex is formed, the water flow rate decreases and the pressure on the upper wall of the water inlet channel increases. Therefore, the real-time sensing data of the pressure pulsation sensor can be used to determine whether a vortex is formed in the water inlet channel. The specific sensor setting method is to use the upper wall of the water inlet channel from the water inlet channel inlet to the lower end of the water inlet channel pump shaft. The specific setting range is shown in the figure. Three pressure pulsation sensors are set on the water inlet flow channel section, and the pressure pulsation sensors are respectively located at -40°, 0°, and 40° to the plumb line on the section.

[0066] (2) When the water flows into the water inlet channel, it will flow obliquely upward along the upper wall of the water inlet channel. Due to the diversion effect of the guide groove, the water flow reduces the boundary layer separation phenomenon, so that the velocity gradient between the water flow near the wall and the center water flow is reduced, the water flow velocity in the water inlet channel is uniformed, and the flow field structure is improved.

[0067] (3) When the water flow rate in the water inlet channel decreases, boundary layer separation is more likely to occur in the water inlet channel, forming backflow and vortex. At this time, the pressure on the wall of the water inlet channel rises. After being monitored and identified by the pressure pulsation sensor, the hydraulically movable guide grid rises, which can break up the vortex structure and effectively prevent the formation of vortex inside the water inlet channel, thereby suppressing the occurrence and development of vortex and improving the operating efficiency of the water jet propulsion pump device.

Claims

1. A water jet pump device for eliminating vortexes in a water inlet flow channel, comprising a water jet pump body (1), a water inlet flow channel (2), and a drive motor (3); one end of the water jet pump body (1) is provided with a water inlet communicating with the water inlet flow channel (2), and the other end is provided with a water outlet (4); a pump shaft (11) of the drive motor (3) extends into the water jet pump body (1), and an impeller is fixed to one end of the pump shaft (11) of the drive motor (3) disposed in the water jet pump body (1); and the device is characterized in that: A pressure pulsation sensor (5) for measuring the pressure of the water flow in the water inlet flow channel (2) on the wall surface of the water inlet flow channel (2) is provided on the upper wall surface of the water inlet flow channel (2); A plurality of guide grooves (6) are provided on the water inlet channel (2) from the inlet of the water inlet channel (2) to the lower end of the pump shaft. Hydraulically movable guide gratings (7) are passed through the guide grooves (6). The guide gratings (7) are movable along the guide grooves (6). The guide grating (7) is arranged on the outer wall of the water inlet channel (2) and is further provided with a hydraulic lift (8). The hydraulic lift (8) is connected to the guide grating (7). The guide grating (7) rises and falls as the hydraulic lift (8) rises and falls, thereby moving the guide grating (7) along the guide groove (6), driving the guide grating (7) to extend into the water inlet channel (2) or exit from the water inlet channel (2); A flexible water stop (12) is provided at the connection between the guide groove (6) and the guide grid bar (7) on the water inlet channel (2); A controller is also provided, which is connected to the pressure pulsation sensor (5) and the hydraulic lift (8) respectively, and the pressure pulsation sensor (5) transmits information on whether a vortex occurs to the controller in real time; When the pressure pulsation sensor (5) identifies the occurrence of a vortex, the pressure pulsation sensor (5) sends a command to the hydraulic lift (8) through the controller, controlling the hydraulic lift (8) to drive the guide grid (7) to rise and extend into the water inlet channel (2); When the pressure pulsation sensor (5) identifies that no vortex has occurred, the controller controls the hydraulic lift (8) to lower the guide grid (7) and withdraw it from the water inlet channel (2).

2. The water jet propulsion pump device according to claim 1, wherein the device comprises: The specific configuration of the pressure pulsation sensor (5) is as follows: The upper wall surface of the water inlet flow channel (2) is used to pass through the inlet of the water inlet flow channel (2) to the lower end of the pump shaft in the water inlet flow channel (2). The specific setting range is shown in the figure. Three pressure pulsation sensors (5) are arranged on the cross section of the water inlet flow channel (2), and the pressure pulsation sensors (5) are respectively located at positions of -40°, 0°, and 40° relative to the vertical line on the cross section; the arrangement of the pressure pulsation sensors (5) is used to accurately determine whether a vortex is formed; wherein D is the diameter of the water outlet.

3. The water flow vortex elimination device for the water inlet channel of a water jet propulsion pump device according to claim 1, characterized in that: set up The diameter of the water outlet (4) is D, and it extends from the inlet of the water inlet channel (2) to the lower end of the pump shaft. A plurality of guide grooves (6) are provided on the water inlet channel (2); The guide groove is wide high rectangular groove.

4. The water flow vortex elimination device for the water inlet channel of a water jet propulsion pump device according to claim 3, characterized in that: The guide grooves (6) are arranged on the upper wall surface of the water inlet channel (2), one is arranged every 22.5 degrees, and a total of 9 guide grooves (6) and guide gratings (7) are arranged. Every three guide gratings (7) form a group, and every three guide gratings (7) are connected to a hydraulic lift (8). A total of three hydraulic lifts (8) control the lifting of the guide gratings (7).

5. The water flow vortex elimination device for the water inlet channel of a water jet propulsion pump device according to claim 1, characterized in that: A top plate (13) is provided outside the water inlet channel (2), and the hydraulic lift (8) is fixedly mounted on the top plate (13).

6. A method for eliminating vortexes by a water flow vortex elimination device in a water inlet channel of a water jet propulsion pump device according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Start the driving motor (3). The pump shaft of the driving motor (3) rotates to drive the impeller to rotate. Water enters from the water inlet of the water inlet channel (2), flows into the water jet propulsion pump body (1) through the water inlet channel (2), and is then ejected from the water outlet (4). S2, the pressure pulsation sensor (5) measures the pressure of the water flow in the water inlet channel (2) on the wall surface of the water inlet channel (2). When the water flow is separated and forms a vortex in the water inlet channel (2), the water flow velocity decreases and the pressure on the upper wall surface of the water inlet channel (2) increases. Therefore, the real-time sensing data of the pressure pulsation sensor (5) can be used to determine whether a vortex is formed in the water inlet channel (2); S3. When no vortex is formed in the water inlet channel (2), the guide groove (6) has a stabilizing effect on the water flow in the water inlet channel (2), which can alleviate the occurrence of boundary layer separation; When a vortex is formed in the water inlet channel (2), the pressure pulsation sensor (5) sends a command to the hydraulic lift (8) through the controller, controlling the hydraulic lift (8) to rise, thereby driving the guide grid (7) to extend into the water inlet channel (2); thus, the guide grid (7) automatically rises after the pressure pulsation sensor (5) recognizes the occurrence of the vortex, thereby making the flow velocity of the water flow in the water inlet channel (2) uniform, changing the flow field structure, disrupting the vortex structure, and improving the flow state of the water flow in the water inlet channel (2) to a great extent; When the vortex in the water inlet flow channel disappears, the pressure pulsation sensor (5) recognizes that the pressure pulsation on the upper wall of the water inlet flow channel (2) decreases, and the pressure pulsation sensor (5) sends a command to the hydraulic lift (8) through the controller to control the hydraulic lift (8) to descend. At this time, the guide grid (7) automatically descends to form a guide groove (6) to stabilize the water flow inside the water inlet flow channel (2).

7. The method according to claim 6, wherein: In step S3: When a vortex occurs in the water inlet channel (2), the pressure pulsation sensor (5) detects that the wall pressure rises, and the guide grating (7) rises. The height of the guide grating (7) in the water inlet channel (2) is The guide bars (7) can break up the vortex when the water flow on the slope side flows back, effectively preventing the formation of the vortex inside the water inlet channel (2), thereby inhibiting the occurrence and development of the vortex and improving the operating efficiency of the water jet propulsion pump device.

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