CN101915514A - A semi-open rotor - Google Patents

Abstract

The invention provides a semi-open rotor, which includes a hollow shaft, main blades and auxiliary blades, the main blades and auxiliary blades are arranged on the outer surface of the hollow shaft, the axial length of the main blades is relatively long, and the main blades at the rear end of the rotor are suspended , forming a semi-open structure, overlapping with the front end of the adjacent rotor in use axially, and having a gap or fit in the radial direction, the radial width of the front part of the main blade on the hollow shaft is smaller than the radial width of the rear part, and the front part of the main blade The rotating diameter is small, the rotating outer diameter of the rear end of the main blade is larger, and the auxiliary blade is arranged at the front end of the rotor, and the axial length is relatively short. The rotating diameter of the front part of the main blade of the rotor of the present invention is small, which plays the role of disturbing the central fluid of the heat exchange tube, and disperses the central fluid to the surroundings. The fluid turbulence effect is better, and the axial length of the auxiliary vane can be adjusted to adjust the driving torque of the fluid to the rotor, which enhances the performance of the rotor adapting to the fluid.

Description

A semi-open rotor

technical field

The invention relates to an interpolation element for enhancing heat transfer, anti-scaling and descaling in heat exchange tubes of equipment such as shell-and-tube heat exchangers and heat exchange reactors.

Background technique

At present, energy saving and emission reduction is a key technology that the whole world attaches great importance to. It is applied to many heat exchangers in many fields such as petroleum, chemical industry, thermal power, nuclear power, metallurgy, light industry, aviation devices and ship vehicles. Among them The most widely used is the shell-and-tube heat exchanger, but the inner wall of these heat exchange tubes generally has layered dirt, which leads to an increase in the resistance of the fluid in the pipeline, and in severe cases, the pipeline will be blocked, and the heat transfer performance will be greatly reduced; The dirt in the heat pipe will seriously reduce the heat transfer efficiency and cause a major waste of energy. At the same time, the dirt is generally corrosive, and the pipe wall will be corroded. If the fluid leaks, it will cause a major safety hazard. Therefore, the traditional treatment method is forced Taking stop-production cleaning will not only delay the production progress of the factory, but also need to pay expensive cleaning fees; in order to better solve these problems, people have been studying the use of non-stop on-line automatic heat transfer and descaling and anti-scaling. methods and devices. In recent years, many anti-scaling and descaling methods and devices have appeared, one of which uses fluid to drive the rotation of the spiral bond to realize the online automatic descaling method. The Chinese patent application number of the spiral bond is: ZL95236063. Scale and anti-scaling cleaning device "invention and creation, the technical solution of this invention is composed of a bond that is roughly equal to the length of the heat exchange tube in the heat exchange tube. The radial dimension of the bond is smaller than the inner diameter of the heat exchange tube. There is an axial fixing frame at the liquid inlet, and there is a liquid inlet hole in the middle part. There is a shaft hole at the head of the axial fixing frame, and a pin shaft is installed in it, and the tail of the pin shaft is connected with a tie; the invention name is " Double-disturbance spiral type enhanced heat exchange and automatic descaling device", the Chinese patent application publication number is CN1424554, the device is used to enhance heat transfer and automatic descaling, including a spiral tie, a fixing frame, and the spiral tie is set in the spiral tube , using the fluid flow through the heat exchange tube to drive the spiral bond to rotate. Since the spiral bond is a whole belt, the heat exchange tube is not straight enough after processing and installation, and there will be uneven gaps between the spiral bond and the inner wall of the heat exchange tube, so the descaling effect of the bond is small and uneven, and the descaling effect not ideal. In the spiral bond method descaling device, the spiral bond is fixed at one end, and the other end is free to swing, and the radial dimension of the bond is smaller than the inner diameter of the heat transfer tube. To sum up, the spiral bond has the following main disadvantages: (1) The bond is a whole, which directly scratches the heat transfer tube and damages the inner wall of the heat transfer tube; (2) When the fluid flows to push the bond to rotate, it requires a large driving torque and consumes more (3) The service life of the bearing used for single-end fixing is short; (4) The field synergy enhanced heat transfer effect generated by the bond is not significant. Afterwards, the Chinese patent number is ZL200520127121.9, which discloses a patent application titled "rotor type self-cleaning enhanced heat transfer device". This device is composed of a fixed frame, a rotor, a flexible shaft and a support tube. The two ends of the heat exchange tube; the outer surface of the rotor has helical ribs, and the rotor has a central hole; the supporting frame is arranged between the rotor and the fixed frame, and the flexible shaft passes through the central hole of the rotor and the supporting tube and is fixed on the two fixed frames. The device has the functions of online automatic scale prevention and descaling and enhanced heat transfer. When the fluid flows in the heat transfer tube along or against the flow, it has the functions of anti-scaling and descaling and enhanced heat transfer. But the disadvantage is that when a certain fluid passes through, the rotation speed of the rotor is determined by the helix angle of the flight. When the flight lead is small, the rotation speed of the rotor is fast, and the resistance to the fluid increases accordingly; in order to solve this problem , Chinese patent application number 200620172805.5, the title of the invention is "low flow resistance rotor with self-cleaning and enhanced heat transfer in the heat transfer tube", the device is composed of a rotor, a support frame and a connecting axis. The two ends of the axis are respectively fixed on the support frame, and multiple rotors are mounted on the connecting axis. The rotor is composed of a hollow shaft and blades. Each blade is inclined in the same shape as the hollow shaft. Adjacent blades are connected end to end. The fluid resistance of the structure is reduced, and the fluid passing performance is good, but its rotation speed is high, and the superposition of the axial force of the rotor exerts a large force on the pendant and the shaft, and the life of the shaft will be reduced. The degree of turbulence of the fluid is not high enough, the temperature difference between the central fluid in the heat exchange tube and the fluid in the boundary layer of the heat exchange tube is large, and it has not been realized that all the fluid in the heat exchange tube can have a good heat exchange effect with the shell medium. The radial width does not change in the axial direction, and the mixing degree of the central layer fluid and the laminar layer fluid in the heat exchange tube is not good enough, which limits the effect of enhancing heat transfer and anti-scaling and descaling capabilities of the rotor.

Contents of the invention

The purpose of this invention is to design a rotor with a new structure, which adopts the combination of main blades and auxiliary blades of different lengths arranged on the hollow shaft, so as to ensure that the central fluid in the heat exchange tube flows to the inner wall of the heat exchange tube, and greatly improve the enhanced heat transfer and performance of the rotor. Anti-scaling and descaling properties.

The specific content of the technical solution of the present invention is: a semi-open rotor, which includes a hollow shaft, main blades and auxiliary blades, the inner diameter of the hollow shaft is larger than the outer diameter of the rotating shaft, the main blades and auxiliary blades are arranged on the outer surface of the hollow shaft, The axial length of the blade is long, and the main blade at the rear end of the rotor is suspended, forming a semi-open structure, which overlaps with the front end of the adjacent rotor in use axially, and has a gap or fit in the radial direction, and the front part of the main blade on the hollow shaft The radial width is smaller than the radial width of the rear part, and the rotating diameter of the front part of the main blade is small, which plays the role of disturbing the central fluid of the heat exchange tube and dispersing the central fluid to the surroundings. The rotating outer diameter of the rear part of the main blade is larger, and The distance between the inner walls of the heat exchange tubes is smaller, which can better destroy the laminar fluid, strengthen the effect of anti-scaling and descaling, and enhance heat transfer. The auxiliary blades are arranged at the front end of the rotor with a short axial length. The role of the central fluid makes the central fluid disperse to the surroundings, increasing the degree of turbulence of the fluid, and the temperature difference between the inner wall fluid of the heat exchange tube and the central fluid in the heat exchange tube is small, thereby improving the heat exchange intensity of the fluid in the heat exchange tube.

The cross-section shape of the hollow shaft of a semi-open rotor of the present invention is hollow conical, hollow cylindrical, hollow nodular or hollow polygonal, and the main blade and auxiliary blade can be provided with a through-hole structure to reduce the impact of the blade on the fluid. Flow resistance saves energy and at the same time saves material.

The two ends of the hollow shaft of a semi-open rotor in the present invention are provided with a coaxial structure, and several rotors are mounted on the rotating shaft between two pendants, and the two ends of the hollow shaft of the rotor are provided with a coaxial structure. The tail of the hollow shaft of one of the adjacent rotors is combined with the head of the hollow shaft of the other rotor. The hollow-shaft coaxial structure of the rotor can be in the form of a ball socket, a cone, a buckle or a universal joint.

The main vane, auxiliary vane and hollow shaft of a semi-open rotor of the present invention are made of polymer material, polymer-based composite material, metal or ceramic material.

The shape of the cross-section of the main blade and the auxiliary blade of the semi-open rotor of the present invention is rectangle, trapezoid, or circular arc, and the main blade and the auxiliary blade can be helical edges.

The blade combined rotor with different axial lengths in the heat exchange tubes involved in the present invention is a semi-open rotor. The internal diameter of the tube, the medium flow rate and temperature in the tube and other working conditions, as well as the manufacturing and processing costs, etc. are determined. The adjacent rotors can adopt synchronous rotation or independent rotation structure.

The beneficial effects of the present invention are: 1, the radial width of the front part of the main blade on the hollow shaft is smaller than the radial width of the rear part, and the rotation diameter of the front part of the main blade is small, which plays the role of disturbing the central fluid of the heat exchange tube, and the central fluid Scattered around, the rear part of the main blade rotates with a larger outer diameter, which has a better turbulence effect on the laminar boundary layer fluid in the heat exchange tube, and has the effect of enhancing heat transfer and anti-scaling and descaling; 2. The auxiliary blade is set on The first half of the hollow shaft of the rotor cooperates with the main blades to improve the effect of the rotor spoiling the central fluid, disperse the central fluid in the heat exchange tube to the surroundings of the heat exchange tube, and enhance the heat exchange effect of the central fluid; 3. The axial length of the auxiliary blade is small , reduces the resistance of the rotor to the fluid, and saves the material cost of the rotor; 4. The axial length of the auxiliary blade can be adjusted to adjust the driving torque of the fluid to the rotor, which enhances the performance of the rotor to adapt to the fluid.

A semi-open rotor of the present invention is installed in the heat exchange tube. According to the specific length of the heat exchange tube, several rotors are connected in series with a rotating shaft and passed through the heat exchange tube. At the same time, the pendant fixed at the end of the heat exchange tube is The two ends of the heat exchange tube are axially fixed to the shaft. When the fluid flows through the main blade and the auxiliary blade, there is a tangential force perpendicular to the radial direction on the rotor, so that the rotor rotates around the shaft, and the rotor will be on the inner wall of the heat exchange tube. It has the effect of anti-scaling and descaling; the hollow shaft of the rotor is equipped with main blades and auxiliary blades with different lengths, and the radial width of the main blades changes in the axial length, and the small-diameter blades disturb the heat exchange The central fluid in the tube, the large-diameter blade spoils the flow of the laminar boundary layer fluid on the inner wall of the heat exchange tube, and the suspended part of the main blade cooperates with the rotor head of the small-diameter blade, which increases the degree of disturbance of the rotor to the fluid. The temperature difference between the fluid in the center of the heat exchange tube and the fluid on the inner wall of the heat exchange tube becomes very small, and the effect of enhancing scale prevention and descaling and enhancing heat transfer is achieved. At the same time, according to actual needs, a hollow structure can be provided on the main blade and the auxiliary blade to reduce the resistance of the rotor to fluid flow, and save the material and price cost of the rotor.

Description of drawings

Fig. 1 is a schematic diagram of the structure of a semi-open rotor of the present invention—a four-leaf rotor.

Fig. 2 is a right side view of Fig. 1 .

Fig. 3 is a schematic diagram of the structure of a semi-open rotor of the present invention—a six-bladed rotor (3 main blades and 3 auxiliary blades).

Fig. 4 is a schematic diagram of the structure of a semi-open rotor of the present invention—a six-blade rotor (2 main blades and 4 auxiliary blades).

Fig. 5 is a schematic diagram of the structure of a semi-open rotor of the present invention—a six-bladed rotor (4 main blades and 2 auxiliary blades).

Fig. 6 is a schematic diagram of a semi-open rotor of the present invention—a four-leaf rotor with a hollow structure.

Fig. 7 is a schematic diagram of the installation and application of a semi-open rotor of the present invention.

In the figure: 1-main blade, 2-auxiliary blade, 3-hollow shaft, 4-ball-socket convex platform, 5-ball-socket concave platform, 6-suspension part, 7-permeable structure, 8-heat exchange tube, 9 -Pendant, 10-rotating shaft, 11-liquid film.

Detailed ways

As shown in Figure 7, the present invention relates to an implementation example of a semi-open rotor. A semi-open rotor of the present invention, a pendant 9 and a rotating shaft 10 are installed in the heat exchange tube 8, and several of the rotors are worn through On the rotating shaft 10 between the two hanging parts 9, the hanging parts 9 are fixed on both ends of the heat exchange tube 8, and the two ends of the rotating shaft 10 are respectively fixed on the hanging parts 9. The rotor is composed of main blades 1 and auxiliary blades 2 with different lengths. Fixed on the hollow shaft 3, the radial width of the main blade 1 changes in the axial direction, and the main blade 1 at the rear part of the rotor is provided with a suspended part 6, which can cooperate with the front end of the adjacent rotor.

As shown in Fig. 1 to Fig. 6, the cross section shape of the hollow shaft 3 of the rotor of the present invention is a hollow cylinder; in Fig. 1 and Fig. 2, two main blades 1 and two auxiliary blades 2 are arranged on the rotor hollow shaft 3; Fig. 3 Shown is a schematic structural diagram of six blades with three main blades 1 and three auxiliary blades 2 arranged on the rotor hollow shaft 3; as shown in Figure 4, it is a six-blade rotor with two main blades 1 and four auxiliary blades 2 Schematic diagram of the structure; FIG. 5 is a schematic diagram of the structure of a six-blade rotor with four main blades 1 and two auxiliary blades 2 . Both ends of the hollow shaft 3 of the rotor are provided with a coaxial structure. In this example, the coaxial structure is provided with a ball socket boss 4 and a ball socket concave table 5 at the head and tail of each hollow shaft 3 respectively. The rotor is mounted on the rotating shaft 10 between the two pendants 9, and the two ends of the hollow shaft 3 are provided with a ball-socket boss 4 and a ball-socket concave table 5, and the head of the hollow shaft 3 of one of the two adjacent rotors The ball-socket boss 4 is combined with another ball-socket recess 5, and the liquid film 11 formed between the joint surfaces reduces the friction between the rotors, thereby reducing the mutual wear of the rotors when they rotate. In addition, another purpose of the coaxial structure It is to keep the adjacent rotors coaxial during operation, and at the same time have a flexible connection structure that adapts to the bending of the heat exchange tube 8. In addition to the ball and socket structure, the coaxial structure can also be conical, buckle or universal joint. When the axiality requirement is not high, the planar structure can be directly adopted. The main blade 1 of the rotor shown in FIG. 6 has a hollow structure 7 .

When the fluid in the heat exchange tube flows through the small-diameter blades of the front part of the semi-open rotor of the present invention, the fluid is acted by the rotor blades to form a swirl flow, and the fluid in the center of the heat exchange tube is dispersed to the periphery of the rotor, increasing the turbulence of the fluid The distance between the center fluid and the fluid near the heat exchange tube 8 is promoted, and the distance between the outer diameter surface of the blades at the rear of the rotor and the inner wall of the heat exchange tube is small, which can effectively disturb the laminar flow boundary layer on the inner wall of the heat exchange tube and improve Anti-scaling and descaling and enhanced heat transfer effects. At the same time, the suspended part 6 of the rear part of the rotor can cooperate with the front part of the adjacent rotor, and further use the rotor to increase the degree of turbulence of the fluid and improve the effect of the enhanced heat transfer of the rotor.

Claims (8)

1. semi-open-type rotor, comprise hollow shaft, primary blades and auxilliary blade, the hollow shaft internal diameter is greater than the external diameter of rotating shaft, primary blades and auxilliary blade are arranged on the hollow shaft outer surface, it is characterized in that: the primary blades axial length is longer, the primary blades of rotor rear end is unsettled, form the semi-open-type structure, axially go up overlaid with the front end of adjacent rotor in the use, the footpath upwards has gap or cooperation, and primary blades forward part radial width is less than the radial width of rear section on the hollow shaft, and primary blades forward part rotating diameter is little, primary blades rear end part rotation external diameter is bigger, less with heat exchanger tube inwall distance, auxilliary blade is arranged on the rotor front end, and axial length is shorter.

2. a kind of semi-open-type rotor according to claim 1 is characterized in that: the hollow shaft cross sectional shape of rotor is open circles taper, hollow cylinder, hollow nodal figure or hollow many prismatics.

3. a kind of semi-open-type rotor according to claim 1 is characterized in that: the hollow shaft two ends of rotor are provided with coaxial configuration, and the head of the afterbody of the hollow shaft of two one of them rotors of adjacent rotors and the hollow shaft of another rotor combines.

4. a kind of semi-open-type rotor according to claim 3 is characterized in that: coaxial configuration can be ball-and-socket mode, circular cone mode, buckle mode or universal joint mode.

5. a kind of semi-open-type rotor according to claim 1 is characterized in that: the primary blades of rotor, auxilliary blade and hollow shaft are by macromolecular material, polymer-based composite, metal or ceramic material.

6. a kind of semi-open-type rotor according to claim 1 is characterized in that: the shape of the cross section of primary blades and auxilliary blade is rectangle, trapezoidal or circular arc.

7. a kind of semi-open-type rotor according to claim 1 is characterized in that: on primary blades and the auxilliary blade hollow structure can be set.

8. a kind of semi-open-type rotor according to claim 1 is characterized in that: primary blades and auxilliary blade can be scroll.

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