A stirrer
By combining swept-back and axial-flow impellers, pressurized liquid is used to flush the deposited material, solving the problem of difficult start-up of agitators in high solids content systems and achieving smooth start-up and efficient mixing at low power.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HANGZHOU YUANZHENG CHEM ENG TECH EQUIP CO LTD
- Filing Date
- 2025-06-23
- Publication Date
- 2026-06-16
AI Technical Summary
Existing agitators are difficult to start in high solids content deposition systems, especially after high solids particles have been deposited.
The design employs a swept-back impeller, allowing pressurized liquid to exit from the cavity of the stirring shaft through the rear end of the swept-back impeller, directly flushing the deposited material, reducing starting resistance, and optimizing the fluid flow path in conjunction with axial-flow impellers.
It significantly reduces the power requirement for stirring start-up, improves the reliability and stability of stirring operation, reduces mechanical wear, and enhances equipment applicability and production efficiency.
Smart Images
Figure CN224358264U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of stirrer technology, and more specifically, to a stirrer. Background Technology
[0002] In numerous industrial sectors such as chemical, metallurgical, food, and pharmaceutical industries, solid-liquid suspension is a common and crucial type of stirring operation. Through the action of a stirrer, solid particles are dispersed into the liquid phase, forming a solid-liquid mixture, i.e., a suspension (slurry). This process not only increases the contact area between the solid and liquid phases but also generates strong turbulence in the suspension through stirring, effectively reducing the mass transfer resistance of the liquid film on the particle surface. This enhances the mass transfer process, creating favorable conditions for the smooth progress of chemical reactions and significantly improving equipment production efficiency.
[0003] Currently, research on solid-liquid suspension systems mainly focuses on the suspension characteristics of low-concentration suspensions. However, in actual industrial production processes, many processes involve high solid content, such as solution concentration and crystallization, melt crystallization, and the slurrying and washing of solid particles. These processes typically have high solid content, and once solid particle deposition occurs, restarting stirring becomes extremely difficult.
[0004] Therefore, how to solve the problem of difficulty in starting up existing agitators in high solids content deposition systems is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content
[0005] In view of this, the purpose of this utility model is to provide a stirrer that can be smoothly started in a high solids content deposition system.
[0006] To achieve the above objectives, this utility model provides the following technical solution:
[0007] A stirrer includes a swept-back impeller, which comprises a stirring shaft and swept-back impeller blades. The swept-back impeller blades are disposed circumferentially on the stirring shaft. Both the stirring shaft and the swept-back impeller blades are hollow structures, and the cavity of the stirring shaft is connected to the cavity of the swept-back impeller blades so that pressurized liquid flowing through the cavity of the stirring shaft is discharged from the tail end of the cavity of the swept-back impeller blades.
[0008] Preferably, the bottom of the tail end of the swept-back impeller is provided with an opening, which communicates with the cavity of the swept-back impeller.
[0009] Preferably, the swept-back impeller has three blades, which are evenly distributed around the circumference of the impeller shaft via a first bushing. The first bushing has a through hole for connecting the cavity of the impeller shaft and the cavity of the swept-back impeller.
[0010] Preferably, the cross-section of the swept-back impeller along the axial direction of the agitator shaft is triangular, and the liquid-facing angle of the swept-back impeller is 30 degrees to 75 degrees.
[0011] Preferably, the sweep angle of the swept-back impeller blades is 40-60 degrees.
[0012] Preferably, it also includes an axial flow impeller disposed on the stirring shaft, the axial flow impeller being located above the swept impeller.
[0013] Preferably, the axial flow impeller has three blades, which are evenly distributed around the circumference of the impeller shaft via impeller seats and a second shaft sleeve.
[0014] Preferably, the axial flow impeller is a curved impeller, and the angle between the curved surface of the axial flow impeller and its own centerline is 5 degrees to 20 degrees.
[0015] Preferably, the axial flow impeller is inclined, with the root inclination angle of the axial flow impeller being 25-30 degrees and the end inclination angle of the axial flow impeller being 35-55 degrees.
[0016] Preferably, it also includes a drive device for driving the stirring shaft to rotate.
[0017] The agitator provided by this utility model includes a swept-back agitator, which comprises an agitator shaft and swept-back agitator blades. The swept-back agitator blades are arranged circumferentially on the agitator shaft. Both the agitator shaft and the swept-back agitator blades are hollow structures, and the cavity of the agitator shaft is connected to the cavity of the swept-back agitator blades. This allows pressurized liquid flowing through the cavity of the agitator shaft to be discharged from the rear end of the cavity of the swept-back agitator blades. Pressurized washing liquid is introduced from the cavity of the agitator shaft, passes through the cavity of the swept-back agitator blades, and then rushes out from the rear end of the cavity of the swept-back agitator blades. This allows the pressurized liquid to directly wash the deposited material around the swept-back agitator blades, thereby effectively loosening the deposited solid particles, reducing the resistance when the swept-back agitator blades start up, and enabling the swept-back agitator blades to start stirring smoothly with low power consumption. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.
[0019] Figure 1 This is a schematic diagram of the structure of the stirrer provided by this utility model;
[0020] Figure 2A schematic diagram of the swept-back stirring blade provided by this utility model;
[0021] Figure 3 This is a cross-sectional view of the swept-back stirring blade provided by this utility model.
[0022] Figure 4 This is a top view of the swept-back stirring blade provided by this utility model;
[0023] Figure 5 This is a top view of the axial flow stirring blade provided by this utility model;
[0024] Figure 6 This is a schematic diagram of the axial flow stirring blade provided by this utility model;
[0025] Figure 7 A schematic diagram showing the root inclination angle of the axial flow stirring blade provided by this utility model;
[0026] Figure 8 This is a schematic diagram showing the end inclination angle of the axial flow stirring blade provided by this utility model.
[0027] Figure label:
[0028] 1-Stirring shaft;
[0029] 2-Sweep-back impeller, 21-Opening;
[0030] 3-Axial flow type impeller blades;
[0031] 4-Drive unit;
[0032] 5-Rotary joint. Detailed Implementation
[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0034] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0035] It should be noted that the directional terms such as "up" and "down" in the following text are defined based on the accompanying drawings in the instruction manual.
[0036] The core of this invention is to provide a stirrer that can be smoothly started in a high solids content deposition system.
[0037] Please refer to Figure 1 An agitator includes a swept-back impeller.
[0038] Specifically, the swept-back impeller includes an impeller shaft 1 and swept-back impeller blades 2. The swept-back impeller blades 2 are located circumferentially around the impeller shaft 1. Both the impeller shaft 1 and the swept-back impeller blades 2 are hollow structures, and the cavity of the impeller shaft 1 is connected to the cavity of the swept-back impeller blades 2. This allows pressurized liquid flowing through the cavity of the impeller shaft 1 to be discharged from the rear end of the cavity of the swept-back impeller blades 2. Pressurized washing liquid is introduced from the cavity of the impeller shaft 1, passes through the cavity of the swept-back impeller blades 2, and then rushes out from the rear end of the cavity of the swept-back impeller blades 2. This allows the pressurized liquid to directly wash the deposited material around the swept-back impeller blades 2, thereby effectively loosening the deposited solid particles, reducing the resistance when the swept-back impeller blades 2 are started, and enabling the swept-back impeller blades 2 to start stirring smoothly with low power consumption.
[0039] The agitator designed in the above manner uses pressurized washing liquid to rush out from the tail end of the swept-back agitator blade 2, directly washing away the deposited material around the blade, effectively loosening the deposited solid particles, significantly reducing the resistance when the swept-back agitator blade 2 starts up, enabling the swept-back agitator blade 2 to start up smoothly with low power consumption, and improving the reliability and stability of the agitation operation.
[0040] The power required for start-up of the agitator is significantly reduced through the flushing action of pressurized liquid. Compared with traditional agitators, the ratio of start-up power to normal operating power is significantly lower. This not only solves the problem of requiring additional power to start up after the sedimentation of high-solids-content particles, but also improves the applicability and reliability of the agitator in high-solids-content systems.
[0041] Please refer to Figure 2 The bottom of the rear end of the swept-back stirring blade 2 is provided with an opening 21, which is connected to the cavity of the swept-back stirring blade 2.
[0042] It should be noted that the opening 21 at the bottom of the swept-back impeller 2 allows pressurized liquid to be directly ejected from the bottom of the impeller's tail end. This enhances the scouring force of the liquid on the surrounding deposited material. Compared to discharging liquid from the side of the impeller or other locations, the opening 21 at the bottom of the tail end can more directly impact the solid particles deposited below and around the impeller. The impact force of the pressurized liquid can more effectively loosen tightly packed solid particles, making it easier for the deposits to be redispersed into the liquid phase. This significantly reduces the resistance during the start-up of the swept-back impeller 2, ensuring that the swept-back impeller 2 can start up smoothly with low power consumption.
[0043] Furthermore, the design of the bottom opening 21 at the tail end of the swept-back impeller 2 reduces the resistance experienced by the impeller during startup and operation, reduces the wear of mechanical parts, and thus effectively reduces the additional mechanical load on the impeller caused by sediment accumulation, reduces the probability of mechanical failure, and improves the reliability of the equipment. This not only reduces the maintenance cost of the equipment but also reduces downtime and improves production efficiency.
[0044] In the above case, the swept-back stirring blade 2 is provided with three blades. The three swept-back stirring blades 2 are evenly arranged around the stirring shaft 1 through the first bushing. The first bushing is provided with a through hole for connecting the cavity of the stirring shaft 1 and the cavity of the swept-back stirring blade 2.
[0045] Understandably, the three swept-back impeller blades 2 are evenly distributed around the stirring shaft 1 via the first bushing. This arrangement makes the overall structure of the impeller more stable. Compared to single or double-blade designs, the three blades can more effectively transmit the stirring force to all areas of the liquid phase, reducing dead zones and ensuring that the solid-liquid suspension reaches an ideal mixing state. Moreover, the synergistic effect of the three swept-back impeller blades 2 can generate a more complex turbulent structure, which not only enhances the mixing effect between solid particles and the liquid phase but also makes the particles more evenly distributed in the liquid phase. This is particularly suitable for suspensions with high solid content, effectively preventing local particle aggregation and thus improving stirring efficiency.
[0046] Furthermore, the first bushing not only fixes the position of the impeller but also ensures the connectivity between the stirring shaft 1 and the impeller cavity through the through hole. This effectively reduces vibration and impact caused by liquid flow during stirring, improving the structural stability of the impeller. The design of the three swept-back impeller blades 2 allows the liquid to form a more optimized flow path during stirring. The liquid enters the cavity of the swept-back impeller blades 2 from the cavity of the stirring shaft 1 through the through hole of the first bushing and exits from the tail end of the blades. This flow path not only improves the flow efficiency of the liquid but also enhances the scouring and dispersion effect of the liquid on solid particles, further optimizing the stirring effect.
[0047] The first bushing is welded to the swept-back impeller 2. In practical applications, there are no restrictions on the connection method between the first bushing and the swept-back impeller 2.
[0048] Furthermore, the swept-back impeller 2 has a triangular cross-section along the axial direction of the stirring shaft 1, and the liquid-facing angle of the swept-back impeller 2 is 30 degrees to 75 degrees.
[0049] It should be noted that the angle A of the liquid-facing surface is as follows: Figure 3 As shown, the design of the liquid-facing angle A optimizes the fluid flow path, improves stirring efficiency, and reduces fluid resistance. The range of liquid-facing angle A is 30 degrees to 75 degrees to ensure that the stirrer achieves optimal stirring performance under different operating conditions. In high-solids-content systems, the design of the liquid-facing angle A helps pressurized liquids more effectively dislodge deposited solid particles, reduces starting resistance, and reduces starting power, thereby enabling the stirrer to achieve efficient mixing and suspension with low power consumption, making it particularly suitable for high-solids-content systems.
[0050] Among them, the swept-back impeller 2 has a triangular cross-section along the axial direction of the stirring shaft 1. This shape can efficiently guide fluid flow. During rotation, the triangular cross-section of the impeller allows the fluid to form a stable flow path along the impeller surface, reducing turbulence and eddy current losses. Compared with impellers of other shapes, it can more effectively convert the kinetic energy of the fluid into the useful work required for stirring, improving stirring efficiency. During rotation, it can more evenly distribute the shear force of the fluid, reducing local stress concentration, effectively reducing the mechanical load on the impeller during operation, reducing mechanical wear, and extending the service life of the impeller. Moreover, the triangular cross-section of the impeller structure is more stable and can withstand greater fluid pressure and mechanical load, enabling the impeller to maintain a stable operating state even under complex conditions of high solids content suspensions.
[0051] In the above embodiment, the sweep angle of the swept-back impeller 2 is 40 degrees to 60 degrees.
[0052] It is understandable that the sweep angle B of the swept hollow blade is as follows: Figure 4As shown, the sweep angle B refers to the angle between the longitudinal centerline of the impeller and its leading or trailing edge. The leading edge of the impeller is the front edge of the impeller in the direction of fluid flow; the trailing edge is the rear edge of the impeller in the direction of fluid flow. A swept-back impeller with a sweep angle B of 40-60 degrees can significantly enhance mixing efficiency, allowing the impeller to more effectively guide fluid flow during rotation, generating stronger turbulence and shear force, resulting in a more uniform distribution of solid particles in the liquid phase and improving solid-liquid mixing. This is particularly suitable for mixing suspensions with high solid content. In practical agitator design, the sweep angle B can optimize the fluid flow path, reduce energy loss and eddies during mixing, and improve mixing efficiency. The specific value of the sweep angle B can be adjusted according to the size of the agitator, the viscosity of the mixing medium, and the purpose of mixing.
[0053] Please refer to Figure 1 , Figure 5 , Figure 6 , Figure 7 and Figure 8 It also includes an axial flow type impeller 3 disposed on the stirring shaft 1, the axial flow type impeller 3 being located above the swept-back impeller 2.
[0054] It should be noted that the combined design of the swept-back impeller 2 and the axial-flow impeller 3 achieves a synergistic effect of multi-stage mixing. The swept-back impeller 2 is mainly responsible for the efficient dispersion and mixing of high-solids-content suspensions, while the axial-flow impeller 3, located above it, guides the fluid upward along the stirring shaft 1, forming a more optimized fluid flow path. This combination allows solid particles to be more evenly distributed in the liquid phase, improving stirring efficiency and mixing effect. This design not only enhances the fluid circulation effect but also reduces dead zones, significantly improving mixing uniformity.
[0055] In the above embodiment, the axial flow stirring blade 3 is provided with three blades, and the three axial flow stirring blades 3 are evenly arranged around the stirring shaft 1 through the blade seat and the second shaft sleeve.
[0056] Understandably, the three axial-flow impeller blades 3 are evenly distributed around the stirring shaft 1 via impeller seats and a second shaft sleeve. This arrangement makes the overall structure of the impeller more stable, allowing the stirring force to be evenly distributed across the entire liquid surface. Compared to single or double-blade designs, three blades can more effectively transfer the stirring force to all areas of the liquid phase, reducing dead zones and improving mixing uniformity. The synergistic effect of the three axial-flow impeller blades 3 generates a more complex turbulent structure, which not only enhances the mixing effect of the liquid but also makes the liquid more evenly distributed within the mixing tank. Furthermore, the three axial-flow impeller blades 3 are fixed to the stirring shaft 1 via impeller seats and a second shaft sleeve, making the installation and removal of the blades more convenient. Operators can easily replace or repair individual blades without disassembling the entire stirring shaft 1, simplifying the maintenance process and reducing the time and labor required for maintenance.
[0057] The design of the three axial-flow impeller 3 not only optimizes its own mixing performance, but also forms a highly efficient multi-stage mixing system with the swept-back impeller 2. This system can better adapt to the mixing requirements under different working conditions, improve the stability and reliability of the entire mixing system, and ensure the efficient operation of the mixing process.
[0058] Please refer to Figure 5 and Figure 6 The axial-flow impeller 3 is a curved impeller, with the angle between the curved surface and its centerline ranging from 5 to 20 degrees. The axial-flow impeller 3 is a variable-angle, variable-section impeller; the impeller twists along its diameter, constantly changing its angle and cross-section. By using a variable cross-section, the axial-flow impeller 3 achieves maximum levitation force with minimal power consumption, resulting in low power consumption.
[0059] It should be noted that the curved surface design of the axial flow impeller 3 guides the fluid to flow in a specific direction, reducing the generation of eddies and turbulence. The curvature angle I of the axial flow impeller 3 is the angle between the curved surface and its own centerline. Setting the curvature angle I to 5-20 degrees optimizes the fluid flow characteristics and mixing efficiency. The curvature angle I remains consistent throughout the entire length of the impeller to ensure uniform fluid flow and efficient mixing on the impeller surface. However, the curvature angle I can have different values at different positions on the impeller, but all within the range of 5-20 degrees, to adapt to different mixing requirements and fluid characteristics. Specifically, in the mixing of low-viscosity fluids, a smaller value of I, such as 5-10 degrees, can be used; in the mixing of high-viscosity fluids, a larger value of I, such as 15-20 degrees, can be used. The design of the blade's curved surface with an angle I enables the agitator to generate more uniform axial flow during operation, improving mixing efficiency while reducing energy consumption. It also reduces eddies and shear forces generated during mixing, thereby minimizing damage to the mixing medium.
[0060] Wherein, the width F of the axial flow impeller 3 is (0.12-0.18)E; the total length G of the axial flow impeller 3 is (0.35-0.55)E; the root length H of the axial flow impeller 3 is (0.12-0.18)E; E is the diameter of the axial flow impeller 3. By setting the width, total length and root length of the axial flow impeller 3 to the above range, the maximum levitation force can be generated with the minimum power consumption.
[0061] Please refer to Figure 7 and Figure 8 The axial flow impeller 3 is inclined, with the root inclination angle of the axial flow impeller 3 being 25-30 degrees and the end inclination angle of the axial flow impeller 3 being 35-55 degrees.
[0062] Understandably, the root inclination angle C refers to the angle between the line connecting the inner edges of the blade root section and the blade centerline, while the tip inclination angle D refers to the angle between the line connecting the inner edges of the blade tip section and the blade centerline. The design of the root inclination angle C and the tip inclination angle D optimizes fluid flow characteristics and mixing efficiency. The root inclination angle C and the tip inclination angle D gradually change along the entire length of the blade to achieve a twisting motion along the diameter, thereby optimizing the fluid flow path and mixing effect. The design of the root inclination angle C and the tip inclination angle D enables the agitator to generate more uniform axial flow during operation, improving mixing efficiency while reducing energy consumption.
[0063] Furthermore, the root inclination angle C and the tip inclination angle D of the impeller range from 25° to 35° and 35° to 55°, respectively. The smaller root inclination angle ensures smooth fluid entry at the impeller root, while the larger tip inclination angle effectively guides rapid fluid discharge at the impeller tip, reducing the generation of eddies and turbulence. This design enables the impeller to generate more uniform axial flow in the fluid, making the fluid flow on the impeller surface smoother and reducing the generation of eddies and turbulence, thereby improving the axial flow efficiency of the fluid. It is particularly suitable for high solids content systems, effectively preventing the deposition and aggregation of solid particles and improving the mixing effect.
[0064] In stirring low-viscosity fluids, the root angle C can be relatively small, such as 25-30 degrees, while the tip angle D can be relatively large, such as 45-55 degrees. In stirring high-viscosity fluids, the root angle C can be relatively large, such as 30-35 degrees, while the tip angle D can be relatively small, such as 35-45 degrees. The specific values of the root angle C and tip angle D can be adjusted according to the size of the agitator, the viscosity of the stirring medium, and the purpose of stirring to achieve the best stirring effect.
[0065] This tilted blade design effectively reduces fluid resistance on the blade surface, making the fluid flow more smoothly and improving the axial flow efficiency of the fluid, thereby enhancing the mixing effect. It can also effectively promote fluid mixing, allowing solid particles to be more evenly dispersed in the fluid. It is particularly suitable for high solid content systems, effectively preventing the deposition and aggregation of solid particles and improving the mixing effect.
[0066] In the above embodiments, a drive device 4 for driving the stirring shaft 1 to rotate is also included.
[0067] It should be noted that the stirring shaft 1 is driven to rotate by the driving device 4, which in turn drives the swept-back stirring blade 2 and the axial-flow stirring blade 3 on the stirring shaft 1 to rotate synchronously, so as to achieve the stirring operation.
[0068] In summary, the stirrer provided by this utility model introduces pressurized liquid through the rotary joint 5 at the top of the stirring shaft 1, allowing the pressurized liquid to flow through the inner cavity of the stirring shaft 1 and finally rush out through the tail and opening 21 of the swept-back stirring blade 2, which loosens the solid particles around the blade and reduces the starting power of the stirring blade. After the swept-back stirring blade 2 is started, the high solid content solid particles are stirred and suspended, which, together with the axial flow stirring blade 3 above, makes the solid particles quickly and evenly suspended.
[0069] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.
[0070] The stirrer provided by this utility model has been described in detail above. Specific examples have been used to illustrate the principle and implementation of this utility model. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core idea of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made to this utility model without departing from the principle of this utility model, and these improvements and modifications also fall within the protection scope of this utility model.
Claims
1. A stirrer, characterized in that, include: A swept-back impeller, comprising an impeller shaft (1) and swept-back impeller blades (2), wherein the swept-back impeller blades (2) are disposed circumferentially on the impeller shaft (1), both the impeller shaft (1) and the swept-back impeller blades (2) are hollow structures, and the cavity of the impeller shaft (1) is connected to the cavity of the swept-back impeller blades (2) so that pressurized liquid flowing through the cavity of the impeller shaft (1) is discharged from the end of the cavity of the swept-back impeller blades (2).
2. The stirrer according to claim 1, characterized in that, The swept-back stirring blade (2) has an opening (21) at the bottom of its tail end, and the opening (21) is connected to the cavity of the swept-back stirring blade (2).
3. The stirrer according to claim 2, characterized in that, The swept-back stirring blade (2) has three blades. The three swept-back stirring blades (2) are evenly arranged around the stirring shaft (1) through a first bushing. The first bushing has a through hole for connecting the cavity of the stirring shaft (1) and the cavity of the swept-back stirring blade (2).
4. The stirrer according to claim 1, characterized in that, The swept-back impeller (2) has a triangular cross section along the axial direction of the stirring shaft (1), and the liquid-facing angle of the swept-back impeller (2) is 30 degrees to 75 degrees.
5. The stirrer according to claim 4, characterized in that, The sweep angle of the swept-back impeller (2) is 40-60 degrees.
6. The stirrer according to any one of claims 1-5, characterized in that, It also includes an axial flow type impeller (3) disposed on the stirring shaft (1), the axial flow type impeller (3) being located above the swept impeller (2).
7. The stirrer according to claim 6, characterized in that, The axial flow type stirring blade (3) is provided with three blades, and the three blades are evenly arranged around the stirring shaft (1) through the blade seat and the second shaft sleeve.
8. The stirrer according to claim 7, characterized in that, The axial flow stirring blade (3) is a curved blade, and the angle between the curved surface of the axial flow stirring blade (3) and its own center line is 5 degrees to 20 degrees.
9. The stirrer according to claim 8, characterized in that, The axial flow stirring blade (3) is inclined, the root inclination angle of the axial flow stirring blade (3) is 25 degrees to 30 degrees, and the end inclination angle of the axial flow stirring blade (3) is 35 degrees to 55 degrees.
10. The stirrer according to claim 1, characterized in that, It also includes a drive device (4) for driving the stirring shaft (1) to rotate.