Multi-working-condition water jet propulsion device

Abstract

The invention relates to the related technical field of water jet propulsion devices, in particular to a multi-working-condition water jet propulsion device which comprises a propeller body, the propeller body comprises a water inlet flow channel, an impeller shaft, impeller blades, flow guide cover blades and a nozzle which are sequentially connected, the water inlet flow channel is used for water inflow, and the nozzle is used for water spraying; one end of the impeller shaft penetrates through the water inlet flow channel, the other end of the impeller shaft is connected with the impeller hub, the impeller blades are installed on the impeller hub, and flow guide cover blades are installed at the end, away from the impeller shaft, of the impeller hub; a plurality of water outlets are formed in the surfaces of the impeller blades and the surfaces of the flow guide cover blades, and when the propeller body works, the water outlets are used for supplementing water into the propeller body. According to the multi-working-condition water jet propulsion device, water is supplemented into the propeller main body to prevent the local pressure of the propeller main body from being reduced to be lower than saturated steam pressure, so that the cavitation resistance of the propeller main body is improved, and the stability of the internal flow state is maintained.

Description

Technical Field

[0001] The present invention relates to the technical field related to water jet propulsion devices, and in particular to a multi-operating-mode water jet propulsion device. Background Art

[0002] A water jet propulsion device is a unique ship propulsion device. When the water jet propulsion device starts running, it will suck water into a specific internal structure, and then accelerate the sucked water through the internal power system. This acceleration process causes the water to be ejected from the nozzle of the water jet propulsion device at high speed. Since the action of force is mutual, when high-speed water flow is ejected from the water jet propulsion device, a reaction force of equal magnitude and opposite direction will be generated. This reaction force will directly act on the water jet propulsion device, and the water jet propulsion device is installed on the ship, so this reaction force will be transmitted to the ship. This reaction force transmitted to the ship becomes the thrust for the ship to sail forward, thereby pushing the ship to sail on the water in the predetermined direction.

[0003] However, existing water jet propulsion devices are prone to cavitation when running at high speeds (i.e., cavitation is generated when the pressure in a local area of ​​the blade surface drops below the saturated steam pressure). Cavitation will increase the area and intensity of the high turbulent kinetic energy area in the impeller flow channel, making it easier for vortices to form near the blade tip clearance and the blade outlet edge, affecting the conversion of kinetic energy into potential energy. At the same time, the development of cavitation will block the impeller flow channel and affect its internal flow state. The generation of cavitation will also cause changes in the internal flow to produce vibration and noise, affecting the efficiency of the pump.

[0004] Therefore, there is a particular need for an efficient multi-operating-mode water jet propulsion device to minimize the generation of cavitation. Summary of the invention

[0005] The object of the present invention is to provide a multi-operating-mode water jet propulsion device to solve the problem that the existing water jet propulsion device proposed in the above-mentioned background technology is prone to cavitation when running at high speed. Cavitation will increase the area and intensity of the high turbulent kinetic energy area in the impeller flow channel, making it easier to form vortices near the blade tip clearance and the blade outlet edge, affecting the conversion of kinetic energy into potential energy. When the pressure in the local area of ​​the blade surface drops below the saturated steam pressure, cavitation will occur. The development of cavitation will block the impeller flow channel and affect its internal flow state. The generation of cavitation will cause changes in the internal flow to produce vibration and noise, affecting the efficiency of the pump.

[0006] To achieve the above object, the present invention provides the following technical solution: a multi-operating-mode water jet propulsion device, comprising a propeller body, the propeller body comprising a water inlet flow channel, an impeller shaft, an impeller blade, a guide cover blade and a nozzle connected in sequence, the water inlet flow 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, 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 shroud blade is mounted on the end of the impeller hub away from the impeller shaft;

[0008] The surfaces of the impeller blades and the surfaces of the guide cover blades are provided with a plurality 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 intake, and the other end is connected to a plurality of first water outlet holes on the surface of the impeller blade to replenish water to the surface of the impeller blade.

[0010] Optionally, the first water outlet holes are 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 an integrally formed structure.

[0013] Optionally, the guide cover blade includes a guide cover and a guide vane, and the guide cover and the guide vane are an integrally formed structure.

[0014] Optionally, the guide cover is provided with several groups of second water inlet pipes, the inner surface of the guide cover is provided with second water outlet holes, and the surface of the guide blade is provided with third water outlet holes; the second water inlet pipe passes through the guide cover and is connected to the second water outlet holes and / or the third water outlet holes, the second water outlet holes are used to replenish water to the inner surface of the guide cover, and the third water outlet holes are used to replenish water to the surface of the guide blade.

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

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

[0017] Optionally, the water inlet channel is in the shape of a straight cylinder or an arc cylinder;

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

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: when the power system drives the impeller shaft to rotate, the impeller blades also rotate accordingly. During the rotation process, the impeller blades do work on the incoming water flow. The blade shape and angle design of the impeller blades enable the water flow to obtain energy inside the propeller body, increase the flow rate, and change the pressure. The water flow accelerated and energy adjusted by the impeller blades flows out of the nozzle through the guide shroud blades. The reaction force generated by the outflowing high-speed water flow pushes the ship to sail, thereby realizing the propulsion function of the water jet propulsion device. Through the design of the impeller blades and the guide shroud blades, when in use, after the water flow enters the impeller area through the water inlet channel, the water outlet on the surface of the impeller blades replenishes water to the impeller top gap and the impeller inlet and outlet edges when cavitation occurs, so as to prevent the local pressure of this part from dropping below the saturated steam pressure, thereby improving its anti-cavitation ability and maintaining the stability of the internal flow state.

[0020] When water enters the guide shroud blade area from the water inlet channel, the water outlet arranged at the guide shroud blade also replenishes water into the propeller body, thereby changing the flow direction and flow velocity distribution of the water flow, reducing the turbulence of the water flow, and improving the stability of the water flow, thereby optimizing the diversion effect. At the same time, it can also prevent the local area pressure at the guide blade from dropping below the saturated steam pressure to cause cavitation, thereby further improving the anti-cavitation ability, alleviating the cavitation phenomenon, and maintaining the stability of the internal flow state. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of a propeller body of a multi-operating-mode water jet propulsion device of the present invention;

[0022] Figure 2 for Figure 1 A schematic diagram of the structure of the thruster body as viewed from above is shown;

[0023] Figure 3 for Figure 1 A partial cross-sectional structural schematic diagram of the thruster body shown;

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

[0025] Figure 5 for Figure 1 The schematic diagram of the structure of the guide shroud blades, impeller shaft and impeller blades of the propeller body shown;

[0026] Figure 6 for Figure 1 A schematic diagram of the partial structure of the guide shroud blade of the propeller body shown;

[0027] Figure 7 for Figure 1A schematic diagram of the structure of the bearing, shaft seal and fairing of the thruster body shown;

[0028] Figure 8 is a schematic structural diagram of a propeller body in another embodiment;

[0029] Fig. 9 for Figure 8 A schematic diagram of the structure of the guide shroud blade;

[0030] Fig.10 It is a schematic structural diagram of the thruster body in yet another embodiment.

[0031] In the figure: water inlet channel 1,

[0032] Impeller shaft 2, impeller blade 3,

[0033] The guide cover blade 4, the guide cover 41 and the guide blade 42, the second water inlet pipe 43,

[0034] Nozzle 5,

[0035] Propeller body 100, impeller hub 21, water outlet, first water inlet pipe 22, first water outlet hole 61, third water outlet hole 63, second water outlet hole 62,

[0036] Diversion nozzle 7 DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] See also Figure 1-10The present invention provides a multi-mode water jet propulsion device, which includes a propeller body 100. The propeller body 100 includes a water inlet channel 1, an impeller shaft 2, an impeller blade 3, a guide cover blade 4 and a nozzle 5 connected in sequence. The water inlet channel 1 has a water inlet for taking in water so that the water flow enters the interior of the propeller body 100. The nozzle 5 has a water spray port with a gradually decreasing cross-section for spraying the water flow inside the propeller body 100 at high speed. One end of the impeller shaft 2 passes through the water inlet channel 1, and then is connected to the external power mechanism of the hull to drive the impeller shaft 2 to rotate through the external power mechanism. The other end of the impeller shaft 2 is connected to the impeller hub 21, and the impeller blade 3 is installed on the impeller hub 21. The impeller hub 21, the impeller shaft 2 and the impeller blade 3 can be a split structure or an integrally formed structure. The impeller hub 21 is equipped with a guide cover blade 4 at one end away from the impeller shaft 2. The guide shroud blade 4 includes a guide shroud 41 and a guide vane 42. The guide shroud 41 is located on the outside of the guide vane 42. The guide vane 42 is installed on the end of the impeller hub 21 away from the impeller shaft 2 through the bearing 8 and the shaft seal 9. The guide vane 42 is fixed and is used to change the flow direction and flow velocity distribution of the water flow, reduce the turbulence of the water flow, and improve the stability of the water flow, thereby optimizing the diversion effect. A plurality of water outlets are provided on the surface of the impeller blade 3 and the surface of the guide shroud blade 4. When the propeller body 100 is working, the water outlet is used to add water to the inside of the propeller body 100 to prevent the local pressure inside the propeller body 100 from dropping below the saturated steam pressure, thereby enhancing its anti-cavitation ability and maintaining the stability of the internal flow state.

[0039] The present invention provides a multi-mode water jet propulsion device, and its working process 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 suck the water flow into the inside of the propeller body 100, and push the water flow to the guide vanes 42 at high speed. Through the guidance of the guide vanes 42, the high-speed water flow is finally ejected through the nozzle 5, thereby generating a reverse thrust to drive the hull to travel; while working, another water flow is passed into the impeller blades 3 and the guide cover blades 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 cover blades 4 to the inside of the propeller body 100, so as to replenish water inside the propeller body 100, so as to effectively reduce the occurrence of cavitation and cavitation, maintain the stability of the internal flow state, and finally achieve the effect of improving the propulsion efficiency.

[0040] In a 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 blade 3. The first water outlet holes 61 are used to replenish water to the surface of the impeller blade 3.

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

[0042] In a preferred embodiment, the impeller shaft 2, the impeller hub 21 and the impeller blades 3 are an integrally formed structure. This design makes the structure of the propeller body 100 simple and has a longer service life, and there is no connection gap between the impeller shaft 2, the impeller hub 21 and the impeller blades 3, which can prevent the water flow of the first water inlet pipe 22 from overflowing from the connection gap, and avoids the gap and the overflowing water flow from disturbing the water flow inside the propeller body 100, thereby improving the propulsion efficiency.

[0043] Similarly, in a preferred embodiment, the guide cover 41 and the guide blade 42 are an integrally formed structure. The design of the integrally formed structure makes the structure of the guide cover blade 4 simpler, reduces the manufacturing cost, and increases the service life. At the same time, it also has the above-mentioned function of avoiding the disturbance of the water flow inside the propeller body 100 by the unexpected overflow water flow, thereby improving the propulsion efficiency.

[0044] Of course, if Figure 5-7 As shown, the guide cover 41 and the guide blades 42 are of split design, which are connected through a water pipe joint and several groups of second water inlet pipes 43 in the guide cover 41, and then the water flow is dispersed to several second water outlet holes 62 and third water outlet holes 63, so that the inside of the propeller body 100 is replenished with water. It can also achieve the optimization of the diversion effect by changing the flow direction and flow velocity distribution of the water flow, reducing the turbulence of the water flow, and improving the stability of the water flow. At the same time, it can also avoid the occurrence of cavitation caused by the pressure in the local area of ​​the guide blade dropping below the saturated steam pressure, thereby further improving the anti-cavitation ability, alleviating the cavitation phenomenon, maintaining the stability of the internal flow state, and improving the propulsion efficiency.

[0045] In a specific embodiment, the air deflector 41 is provided with a plurality of groups of second water inlet pipes 43. The inner surface of the air deflector 41 is provided with a second water outlet hole 62, and the surface of the guide blade 42 is provided with a third water outlet hole 63. The outer end of the second water inlet pipe 43 is connected to an external water pumping device. The second water inlet pipe 43 passes through the air deflector 41 and is connected 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 air deflector 41, and the third water outlet hole 63 is used to replenish water to the surface of the guide blade 42, thereby preventing the pressure of a local area inside the propeller body 100 from dropping below the saturated steam pressure.

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

[0047] Preferably, if Fig. 9 As shown, the 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 close to the water inlet channel 1 and the side close to the nozzle 5). The direction of the third water outlet 63 is selected according to the simulation results of the water flow state inside the propeller body 100, and its purpose is to change the flow direction and flow velocity distribution of the water flow, reduce the turbulence of the water flow, and improve the stability of the water flow, thereby optimizing the diversion effect, and at the same time, avoiding the occurrence of local turbulence and vortex, thereby reducing energy loss.

[0048] Optionally, a guide nozzle 7 is installed between the nozzle 5 and the guide cover blade 4. The guide nozzle 7 is used to cooperate with the guide blade 42 to adjust the flow state of the water flow. The cross section of the nozzle 5 is gradually reduced so as to spray the water flow more efficiently.

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

[0050] Optionally, the water inlet channel 1 may be in a straight cylindrical shape or an arcuate cylindrical shape. When the water inlet channel 1 is in an arcuate cylindrical shape, the end of the impeller shaft 2 away from the impeller blades 3 passes through the pipe wall of the water inlet channel 1 and is connected to an external power device to drive the impeller blades 3 to rotate. When the water inlet channel 1 is in a straight cylindrical shape, the impeller shaft 2 may be coaxial with the water inlet channel 1.

[0051] like Figure 6 As shown, a plurality of grooves are also provided on the inner surface of the guide cover 41. Through the provision of the grooves, when water enters the guide cover blade area from the water inlet channel 1, the water flow entering the guide blade 42 passes through the grooves on the inner surface. The grooves change the flow direction and velocity distribution of the water flow, reduce the degree of turbulence of the water flow, and improve the stability of the water flow, thereby optimizing the diversion effect. This is because the grooves can guide the water flow to flow along a specific path, avoid local turbulence and vortexes, and thus reduce energy loss. The structure of the grooves cooperates with the water replenishment at the outlet to further enhance its anti-cavitation ability, thereby improving the propulsion efficiency.

[0052] Compared with the prior art, the beneficial effects of the present invention are as follows: when the power system drives the impeller shaft 2 to rotate, the impeller blade 3 also rotates accordingly. During the rotation process, the impeller blade 3 performs work on the incoming water flow. The blade shape and angle design of the impeller blade 3 enable the water flow to obtain energy inside the propeller body 100, increase the flow rate, and change the pressure. The water flow accelerated and energy adjusted by the impeller blade 3 flows out of the nozzle 5 through the guide cover blade 4. The reaction force generated by the outflowing high-speed water flow pushes the ship to sail, thereby realizing the propulsion function of the water jet propulsion device. Through the design of the impeller blade 3 and the guide cover blade 4, when the water flow enters the impeller area through the water inlet channel 1, the water outlet on the surface of the impeller blade 3 replenishes water to the impeller blade top gap and the impeller inlet and outlet edges when cavitation occurs, so as to prevent the local pressure of this part from being reduced to below the saturated steam pressure, thereby improving its anti-cavitation ability and maintaining the stability of the internal flow state.

[0053] When water enters the area of ​​the guide shroud blade 4 from the water inlet channel, the water outlet arranged at the guide shroud blade 4 also replenishes water into the propeller body 100, thereby changing the flow direction and flow velocity distribution of the water flow, reducing the turbulence of the water flow, and improving the stability of the water flow, thereby optimizing the diversion effect. At the same time, it can also prevent the pressure in the local area of ​​the guide blade 42 from dropping below the saturated steam pressure to generate cavitation, thereby further improving the anti-cavitation ability, alleviating the cavitation phenomenon, maintaining the stability of the internal flow state, and ultimately improving the propulsion efficiency.

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

Claims

1. A multi-operating-mode water jet propulsion device, characterized in that: including the propeller body, The propeller body comprises a water inlet channel, an impeller shaft, impeller blades, a guide cover blade 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, 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 shroud blade is mounted on the end of the impeller hub away from the impeller shaft; The surfaces of the impeller blades and the surfaces of the guide cover blades are provided with a plurality of water outlets. When the propeller body is working, the water outlets are used to replenish water into the propeller body.

2. A multi-operating-mode water jet propulsion device according to claim 1, characterized in that: A first water inlet pipe is arranged inside the impeller shaft, one end of which is used for water intake, and the other end of which is connected to a plurality of first water outlet holes on the surface of the impeller blades to replenish water to the surface of the impeller blades.

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

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

5. A multi-mode water jet propulsion device according to any one of claims 1 to 4, characterized in that: The impeller shaft, impeller hub and impeller blades are an integrally formed structure.

6. A multi-mode water jet propulsion device according to any one of claims 1 to 4, characterized in that: The guide cover blade comprises a guide cover and a guide vane, and the guide cover and the guide vane are an integrally formed structure.

7. The multi-operating-mode water jet propulsion device according to claim 6, characterized in that: The guide cover is provided with a plurality of groups of second water inlet pipes, the inner surface of the guide cover is provided with second water outlet holes, and the surface of the guide blade is provided with third water outlet holes; the second water inlet pipe passes through the guide cover and is connected to the second water outlet holes and / or the third water outlet holes, the second water outlet holes are used to replenish water to the inner surface of the guide cover, and the third water outlet holes are used to replenish water to the surface of the guide blade.

8. The multi-mode water jet propulsion device according to claim 7, characterized in that: The outlet direction of the second water outlet hole is toward the impeller blade, so that the second water outlet hole and the first water outlet hole cooperate to replenish water to the area of ​​the impeller blade.

9. A multi-operating-mode water jet propulsion device according to any one of claims 1-4, 7-8, characterized in that: A guide nozzle is installed between the nozzle and the guide cover blade, and the guide nozzle is used to cooperate with the guide blade to adjust the flow state of the water flow.

10. A multi-operating-mode water jet propulsion device according to any one of claims 1-4, 7-8, characterized in that: The water inlet channel is in the shape of a straight cylinder or an arc cylinder; When the water inlet channel is in an arc-shaped cylinder, one end of the impeller shaft away from the impeller blade passes through the tube 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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