A multi-condition water jet propulsion device

Abstract

This invention relates to the technical field of waterjet propulsion devices, and more particularly to a multi-condition waterjet propulsion device, comprising a propeller body, which includes a water inlet channel, an impeller shaft, impeller blades, a guide vane, and a nozzle connected in sequence. The water inlet channel is used for water intake, and the nozzle is used for water spraying. One end of the impeller shaft passes through the water inlet channel, and the other end of the impeller shaft is connected to an impeller hub. The impeller blades are mounted on the impeller hub, and a guide vane is mounted on the end of the impeller hub away from the impeller shaft. The surfaces of the impeller blades and the guide vane are provided with a plurality of water outlets, which are used to replenish water into the propeller body when the propeller body is operating. The multi-condition waterjet propulsion device of this invention, by replenishing water into the propeller body, prevents its local pressure from dropping below the saturated steam pressure, thereby improving its anti-cavitation capability and maintaining the stability of the internal flow.

Description

Technical Field

[0001] This invention relates to the technical field of water jet propulsion devices, and in particular to a multi-condition water jet propulsion device. Background Technology

[0002] Waterjet propulsion is a unique type of ship propulsion equipment. When the waterjet propulsion system starts operating, it draws water into a specific internal structure and then accelerates the water through its internal power system. This acceleration process causes the water to be ejected at high speed from the nozzle of the waterjet propulsion system. Since forces are reciprocal, when the high-speed water jet is ejected from the waterjet propulsion system, it generates a reaction force of equal magnitude and opposite direction. This reaction force acts directly on the waterjet propulsion system, which is installed on the ship. Therefore, this reaction force is transmitted to the ship, and this reaction force transmitted to the ship becomes the thrust that propels the ship forward, thus propelling the ship on the water surface in a predetermined direction.

[0003] However, existing waterjet propulsion devices are prone to cavitation when operating at high speeds (i.e., when the pressure in a local area on the blade surface drops below the saturated steam pressure, cavitation bubbles are generated). Cavitation increases the area and intensity of high turbulent kinetic energy regions within the impeller flow channel, making it easier for vortices to form near the blade tip clearance and blade exit edge, affecting the conversion of kinetic energy to potential energy. At the same time, the development of cavitation bubbles can block the impeller flow channel, affecting its internal flow pattern. The generation of cavitation can also lead to changes in internal flow, generating vibration and noise, and affecting pump efficiency.

[0004] Therefore, there is a particular need for a highly efficient multi-condition water jet propulsion device to minimize cavitation. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-condition water jet propulsion device to solve the problems mentioned in the background art. Existing water jet propulsion devices are prone to cavitation when operating at high speeds. Cavitation increases the area and intensity of high turbulent kinetic energy regions in the impeller flow channel, making it easier for vortices to form near the blade tip clearance and blade exit edge, affecting the conversion of kinetic energy to potential energy. When the pressure in a local area on the blade surface drops below the saturated steam pressure, cavitation bubbles will be generated. The development of cavitation bubbles will block the impeller flow channel, affecting its internal flow state. The generation of cavitation will lead to changes in internal flow, resulting in vibration and noise, and affecting pump efficiency.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a multi-condition water jet propulsion device, comprising a propeller body, the propeller body comprising a water inlet channel, an impeller shaft, impeller blades, a guide vane, and a nozzle connected in sequence, wherein the water inlet channel is used for water intake, and the nozzle is used for water spraying;

[0007] One end of the impeller shaft passes through the water inlet channel, and the other end of the impeller shaft is connected to the impeller hub. The impeller blades are mounted on the impeller hub, and a guide vane is installed on the end of the impeller hub away from the impeller shaft.

[0008] The impeller blades and the guide vanes are provided with a number of water outlets. When the propeller body is working, the water outlets are used to replenish water into the propeller body.

[0009] Optionally, a first water inlet pipe is provided inside the impeller shaft. One end of the first water inlet pipe is used for water inlet, and the other end is connected to a plurality of first water outlet holes on the surface of the impeller blades for replenishing water to the surface of the impeller blades.

[0010] Optionally, the first water outlet is distributed on the blade edge and / or blade side surface of the impeller blade.

[0011] Optionally, the first water outlet holes are evenly distributed.

[0012] Optionally, the impeller shaft, impeller hub, and impeller blades are integrally formed.

[0013] Optionally, the air deflector includes an air deflector and air deflector blades, which are integrally formed.

[0014] Optionally, the flow guide shroud is provided with several sets of second water inlet pipes, the inner surface of the flow guide shroud is provided with a second water outlet hole, and the surface of the flow guide blade is provided with a third water outlet hole; the second water inlet pipe passes through the flow guide shroud and is connected to the second water outlet hole and / or the third water outlet hole, the second water outlet hole is used to replenish water to the inner surface of the flow guide shroud, and the third water outlet hole is used to replenish water to the surface of the flow guide blade.

[0015] Optionally, the outlet direction of the second water outlet is toward the impeller blade, so that the second water outlet and the first water outlet work together to replenish water to the area of ​​the impeller blade.

[0016] Optionally, a guide nozzle is installed between the nozzle and the guide vane, the guide nozzle being used to cooperate with the guide vane to adjust the flow state of the water.

[0017] Optionally, the water inlet channel is a straight cylindrical or arc-shaped cylindrical channel;

[0018] When the water inlet channel is an arc-shaped cylindrical shape, the end of the impeller shaft away from the impeller blade passes through the pipe wall of the water inlet channel and is connected to an external power device to drive the impeller blade to rotate.

[0019] Compared with existing technologies, the beneficial effects of this invention are as follows: In this multi-condition waterjet propulsion device, when the power system drives the impeller shaft to rotate, the impeller blades also rotate. During rotation, the impeller blades perform work on the incoming water flow. The design of the impeller blade shape and angle allows the water flow to gain energy within the propeller body, increasing its velocity and changing its pressure. After being accelerated and energy-adjusted by the impeller blades, the water flow exits from the nozzle through the guide vane. The reaction force generated by the high-speed water flow propels the ship, thus realizing the propulsion function of the waterjet propulsion device. Through the design of the impeller blades and guide vane, during operation, after the water flow enters the impeller area through the inlet channel, the outlet on the impeller blade surface replenishes water to the impeller tip clearance and impeller inlet / outlet edges when cavitation occurs. This prevents the local pressure in these areas from dropping below the saturated steam pressure, thereby improving its anti-cavitation capability and maintaining the stability of the internal flow.

[0020] When water enters the guide vane area from the inlet channel, the outlet at the guide vane also replenishes water into the propeller body. By changing the direction and velocity distribution of the water flow, the turbulence of the water flow is reduced, and the stability of the water flow is improved, thereby optimizing the guiding effect. At the same time, it can also prevent the pressure in the local area at the guide vane from dropping below the saturated steam pressure and causing cavitation, thereby further improving the anti-cavitation capability, alleviating cavitation phenomena, and maintaining the stability of the internal flow. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the propeller body of a multi-condition water jet propulsion device according to the present invention;

[0022] Figure 2 for Figure 1 A schematic diagram of the thruster body from below;

[0023] Figure 3 for Figure 1 A partial cross-sectional view of the main body of the thruster is shown.

[0024] Figure 4 for Figure 1 A schematic diagram of the impeller shaft and impeller blades of the main body of the propeller is shown;

[0025] Figure 5 for Figure 1 The diagram shows the structure of the propeller body's shroud blades, impeller shaft, and impeller blades.

[0026] Figure 6 for Figure 1 A partial structural schematic diagram of the shroud vanes of the propeller body is shown;

[0027] Figure 7 for Figure 1The diagram shows the structure of the bearings, shaft seals, and fairing of the main thruster body;

[0028] Figure 8 This is a schematic diagram of the thruster body in another embodiment;

[0029] Figure 9 for Figure 8 A schematic diagram of the structure of the guide vane in the middle;

[0030] Figure 10 This is a structural schematic diagram of the thruster body in another embodiment.

[0031] In the diagram: Inlet channel 1,

[0032] 2. Impeller shaft, 3. Impeller blades

[0033] Flow guide vane 4, flow guide 41 and flow guide blade 42, second water inlet pipe 43,

[0034] Nozzle 5,

[0035] The propeller body 100 includes an impeller hub 21, a water outlet, a first water inlet pipe 22, a first water outlet 61, a third water outlet 63, and a second water outlet 62.

[0036] Drain nozzle 7 Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] Please see Figure 1-10This invention provides a multi-condition water jet propulsion device, which includes a propeller body 100. The propeller body 100 includes a water inlet channel 1, an impeller shaft 2, impeller blades 3, a guide vane 4, and a nozzle 5 connected in sequence. The water inlet channel 1 has a water inlet for water intake, allowing water to flow into the interior of the propeller body 100. The nozzle 5 has a spray nozzle with a gradually decreasing cross-section for spraying water from the interior of the propeller body 100 at high speed. One end of the impeller shaft 2 passes through the water inlet channel 1 and is then connected to an external power mechanism of the hull to drive the impeller shaft 2 to rotate. The other end of the impeller shaft 2 is connected to an impeller hub 21, and the impeller blades 3 are mounted on the impeller hub 21. The impeller hub 21, impeller shaft 2, and impeller blades 3 can be a separate structure or an integrally formed structure. The guide vane 4 is installed at the end of the impeller hub 21 away from the impeller shaft 2. The guide vane 4 includes a guide vane 41 and guide vanes 42. The guide vane 41 is located outside the guide vanes 42, and the guide vanes 42 are mounted on the end of the impeller hub 21 away from the impeller shaft 2 via bearings 8 and shaft seals 9. The guide vanes 42 are fixed and are used to change the flow direction and velocity distribution of the water flow, reduce the turbulence of the water flow, improve the stability of the water flow, and thus optimize the guiding effect. The surfaces of the impeller blades 3 and the guide vanes 4 are provided with several water outlets. When the propeller body 100 is working, the water outlets are used to replenish water into the propeller body 100 to prevent the local pressure inside the propeller body 100 from dropping below the saturated steam pressure, thereby improving its anti-cavitation capability and maintaining the stability of the internal flow.

[0039] The present invention provides a multi-condition water jet propulsion device, the working process of which is as follows: an external power mechanism (not shown in the figure) drives the impeller shaft 2 to rotate, and the impeller blades 3 rotate accordingly, thereby generating a suction force to draw water into the propeller body 100 and push the water flow at high speed to the guide vanes 42. Through the guidance of the guide vanes 42, the high-speed water flow is finally ejected through the nozzles 5, thereby generating a reverse thrust to drive the hull. At the same time, another water flow enters the impeller blades 3 and the guide vanes 4 through the water inlet pipe, and flows from the water outlet on the surface of the impeller blades 3 and the surface of the guide vanes 4 to the inside of the propeller body 100 to replenish the water inside the propeller body 100, thereby effectively reducing cavitation and cavitation bubbles, maintaining the stability of the internal flow state, and ultimately improving the propulsion efficiency.

[0040] In one specific embodiment, a first water inlet pipe 22 is provided inside the impeller shaft 2. Preferably, the first water inlet pipe 22 is coaxial with the impeller shaft 2. The inlet of the first water inlet pipe 22 is connected to an external water pumping device, so that one end of the first water inlet pipe 22 is used for water intake. The other end of the first water inlet pipe 22 is connected to a plurality of first water outlet holes 61 on the surface of the impeller blades 3. The first water outlet holes 61 are used to replenish water to the surface of the impeller blades 3.

[0041] Specifically, the first water outlet holes 61 can be distributed at any position on the impeller blade 3. These positions can be locations on the surface of the impeller blade 3 where cavitation or cavitation bubbles are easily generated, as determined by simulation experiments. The arrangement density of the first water outlet holes 61 is also designed according to the simulation experimental results. For example, if a certain position is more prone to cavitation or cavitation bubbles, more first water outlet holes 61 are distributed in that position area. Optionally, the first water outlet holes 61 are distributed in an array or uniformly. In a preferred embodiment, the first water outlet holes 61 can be distributed on the blade edge and / or blade side surface of the impeller blade 3. Preferably, the spacing of the first water outlet holes 61 on the blade edge is smaller than the spacing of the first water outlet holes 61 on the blade side surface.

[0042] In a preferred embodiment, the impeller shaft 2, impeller hub 21, and impeller blades 3 are integrally formed. This design simplifies the structure of the propeller body 100, extends its service life, and eliminates the connection gaps between the impeller shaft 2, impeller hub 21, and impeller blades 3. This prevents water from overflowing from the first inlet pipe 22 through any gaps, thus avoiding disturbance to the water flow inside the propeller body 100 by the gaps and overflowing water, thereby improving propulsion efficiency.

[0043] Similarly, in a preferred embodiment, the fairing 41 and the guide vane 42 are integrally formed. This integrally formed design simplifies the structure of the fairing vane 4, reduces manufacturing costs, increases service life, and also avoids unexpected overflow water from disturbing the water flow inside the propeller body 100, thereby improving propulsion efficiency.

[0044] Of course, such as Figure 5-7 As shown, the guide vane 41 and the guide blade 42 are designed separately. They are connected to several sets of second water inlet pipes 43 inside the guide vane 41 through water pipe joints. The water flow is then dispersed to several second water outlet holes 62 and third water outlet holes 63, so as to replenish water inside the propeller body 100. Similarly, by changing the direction and velocity distribution of the water flow, the degree of water flow turbulence can be reduced and the stability of the water flow can be improved, thereby optimizing the guiding effect. At the same time, it can also prevent the local pressure at the guide blade from dropping below the saturated steam pressure and generating cavitation, thereby further improving the anti-cavitation capability, alleviating cavitation phenomenon, maintaining the stability of the internal flow, and thus improving the propulsion efficiency.

[0045] In one specific embodiment, the guide shield 41 is provided with several sets of second water inlet pipes 43. The inner surface of the guide shield 41 is provided with second water outlet holes 62, and the surface of the guide vanes 42 is provided with third water outlet holes 63. One outer end of the second water inlet pipe 43 is connected to an external pumping device. The second water inlet pipe 43 passes through the guide shield 41 and connects to the second water outlet hole 62 and / or the third water outlet hole 63. The second water outlet hole 62 is used to replenish water to the inner surface of the guide shield 41, and the third water outlet hole 63 is used to replenish water to the surface of the guide vanes 42, thereby preventing the pressure in local areas inside the propeller body 100 from dropping below the saturated steam pressure.

[0046] Preferably, the outlet direction of the second water outlet 62 is towards the impeller blade 3, so that the second water outlet 62 and the first water outlet 61 work together to replenish water to the area of ​​the impeller blade 3, thereby further improving its water replenishment capacity. By adjusting the outlet direction of the second water outlet 62, the stability of the water flow in the impeller blade area can also be adjusted.

[0047] Preferably, such as Figure 9 As shown, a third water outlet 63 is provided on both the front and rear sides of the guide vane 42 (the front and rear sides refer to the side of the guide vane 42 closest to the water inlet channel 1 and the side closest to the nozzle 5). The direction of the third water outlet 63 is selected based on the simulation results of the water flow state inside the propeller body 100. Its purpose is to change the flow direction and velocity distribution of the water flow, reduce the degree of turbulence in the water flow, improve the stability of the water flow, thereby optimizing the guiding effect. At the same time, it avoids the occurrence of local turbulence and vortices, thereby reducing energy loss.

[0048] Optionally, a guide nozzle 7 is installed between the nozzle 5 and the guide vane 4. The guide nozzle 7 is used to cooperate with the guide vane 42 to adjust the flow state of the water. The cross-section of the nozzle 5 is gradually reduced to facilitate more efficient water jetting.

[0049] It is necessary to understand that, such as Figure 8-10 As shown, the present invention provides a multi-condition water jet propulsion device, which can be used in axial flow water jet propulsion devices or other types of water jet propulsion devices. Its principle is to supplement water to the position inside the propulsion body that is prone to cavitation or cavitation bubbles, thereby improving the local pressure at that position, reducing the probability of cavitation or cavitation bubbles in that position, and ultimately maintaining the stability of the internal flow state to improve the propulsion efficiency of the propulsion device.

[0050] Optionally, the inlet channel 1 can be a straight cylinder or an arc-shaped cylinder. When the inlet channel 1 is an arc-shaped cylinder, the end of the impeller shaft 2 away from the impeller blades 3 passes through the wall of the inlet channel 1 and is connected to an external power unit to drive the impeller blades 3 to rotate. When the inlet channel 1 is a straight cylinder, the impeller shaft 2 can be coaxial with the inlet channel 1.

[0051] like Figure 6 As shown, several grooves are also provided on the inner surface of the guide vane 41. Through the design of these grooves, when water enters the guide vane blade area from the inlet channel 1, the water flowing into the guide vane 42 passes through the grooves on the inner surface. The grooves change the direction and velocity distribution of the water flow, reducing turbulence and improving its stability, thereby optimizing the guiding effect. This is because the grooves can guide the water flow along a specific path, avoiding localized turbulence and vortices, thus reducing energy loss. The structure of the grooves, in conjunction with the water supply at the outlet, can further enhance its anti-cavitation capability, thereby improving propulsion efficiency.

[0052] Compared with the prior art, the beneficial effects of this invention are as follows: When the power system drives the impeller shaft 2 to rotate, the impeller blades 3 also rotate. During the rotation, the impeller blades 3 perform work on the incoming water flow. The design of the blade shape and angle of the impeller blades 3 allows the water flow to gain energy inside the propeller body 100, increasing the flow velocity and changing the pressure. After being accelerated and energy-adjusted by the impeller blades 3, the water flow flows out of the nozzle 5 through the guide vane 4. The reaction force generated by the high-speed water flow propels the ship, thus realizing the propulsion function of the water jet propulsion device. Through the design of the impeller blades 3 and the guide vane 4, when the water flow enters the impeller area through the inlet channel 1, the outlet on the surface of the impeller blades 3 replenishes water to the impeller blade tip gap and the impeller inlet and outlet edges when cavitation occurs, preventing the local pressure in this area from dropping below the saturated steam pressure, thereby improving its anti-cavitation capability and maintaining the stability of the internal flow.

[0053] When water enters the guide vane 4 area from the inlet channel, the outlet at the guide vane 4 also replenishes water into the propeller body 100. By changing the direction and velocity distribution of the water flow, the degree of turbulence in the water flow is reduced, and the stability of the water flow is improved, thereby optimizing the guiding effect. At the same time, it can also prevent the local pressure at the guide vane 42 from dropping below the saturated steam pressure and causing cavitation, thereby further improving the anti-cavitation capability, alleviating the cavitation phenomenon, maintaining the stability of the internal flow, and ultimately improving the propulsion efficiency.

[0054] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A multi-condition water jet propulsion device, characterized in that, Including the main body of the thruster, The propeller body includes a water inlet channel, an impeller shaft, impeller blades, a guide vane, and a nozzle connected in sequence. The water inlet channel is used for water intake, and the nozzle is used for water spraying. One end of the impeller shaft passes through the water inlet channel, and the other end of the impeller shaft is connected to the impeller hub. The impeller blades are mounted on the impeller hub, and a guide vane is installed on the end of the impeller hub away from the impeller shaft. The guide vane includes a guide vane and guide vanes. The guide vane is located outside the guide vanes, and the guide vanes are mounted on the end of the impeller hub away from the impeller shaft via bearings and shaft seals. The surface of the impeller blades and the surface of the guide vanes are provided with a number of water outlets. When the propeller body is working, the water outlets are used to replenish water into the propeller body. The impeller blades have a plurality of first water outlet holes on their surface for replenishing water to the impeller blades; the inner surface of the flow guide shroud has a second water outlet hole, and the surface of the flow guide blades has a third water outlet hole. The second water outlet hole is used to replenish water to the inner surface of the flow guide shroud, and the third water outlet hole is used to replenish water to the surface of the flow guide blades. The outlet direction of the second water outlet is towards the impeller blade, so that the second water outlet and the first water outlet work together to replenish water to the area of ​​the impeller blade.

2. The multi-condition water jet propulsion device according to claim 1, characterized in that, The impeller shaft is provided with a first water inlet pipe. One end of the first water inlet pipe is used for water inlet, and the other end is connected to several first water outlet holes on the surface of the impeller blades.

3. A multi-condition water jet propulsion device according to claim 2, characterized in that, The first water outlet is distributed on the blade edge and / or blade side surface of the impeller blade.

4. A multi-condition water jet propulsion device according to claim 3, characterized in that, The first water outlet holes are evenly distributed.

5. A multi-condition waterjet propulsion device according to any one of claims 1-4, characterized in that, The impeller shaft, impeller hub, and impeller blades are integrally formed.

6. A multi-condition water jet propulsion device according to claim 5, characterized in that, The flow guide is provided with several sets of second water inlet pipes, which pass through the flow guide and are connected to the second water outlet and the third water outlet.

7. A multi-condition waterjet propulsion device according to any one of claims 1-4 and 6, characterized in that, A guide nozzle is installed between the nozzle and the guide vane. The guide nozzle is used to cooperate with the guide vane to adjust the flow state of the water.

8. A multi-condition waterjet propulsion device according to any one of claims 1-4 and 6, characterized in that, The water inlet channel is either straight or curved. When the water inlet channel is an arc-shaped cylindrical shape, the end of the impeller shaft away from the impeller blade passes through the pipe wall of the water inlet channel and is connected to an external power device to drive the impeller blade to rotate.

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