CN106440882A - Trapezoidal tilted baffle plate shell and tube type heat exchanger - Google Patents

Abstract

The invention provides a shell-and-tube heat exchanger with trapezoidal inclined baffles, which includes a shell, heat exchange tubes, tube sheets, pull rods and trapezoidal baffles, and two adjacent sets of trapezoidal baffles are orthogonal to each other. Arrangement, each group includes at least two parallel trapezoidal baffles, the trapezoidal baffles are uniformly distributed with a number of holes corresponding to the heat exchange tubes, the heat exchange tubes pass through the holes, the trapezoidal baffles The baffles are arranged obliquely; the edges of the trapezoidal baffles are evenly distributed with fixed pipe holes corresponding to the tie rods, the tie rods pass through the fixed pipe holes and are clamped with the housing, and the tie rods are covered with fixed pipes The fixed pipe distance is fixed on the pull rod by bolts. This type of shell-and-tube heat exchanger with trapezoidal inclined baffles can effectively improve heat exchange efficiency and is easy to process, and has broad application prospects.

Description

Quasi-trapezoidal inclined baffle shell and tube heat exchanger

technical field

The invention relates to the field of heat exchangers, in particular to a trapezoidal inclined baffle shell-and-tube heat exchanger.

Background technique

With the rapid development of economy and industry, countries all over the world are facing the problem of energy shortage, so how to efficiently use existing energy is the focus of people's increasing attention. Among them, the heat exchanger can not only reasonably adjust the temperature of the process medium to meet the needs of the process, but also an effective device for waste heat and waste heat recovery and utilization. At present, the most widely used heat exchanger is the shell and tube heat exchanger. However, due to structural reasons, there is a large flow dead zone and pressure drop along the shell side.

In order to solve the above problems, in recent years, some new shell-and-tube heat exchangers using spiral baffles have been developed in the industry. The disadvantage is that it not only reduces the flow resistance, but also promotes enhanced heat transfer. For example, there is a continuous spiral baffle heat exchanger with continuous curved surface. Compared with the arcuate baffle heat exchanger, this kind of heat exchanger can effectively reduce flow resistance and leakage. However, the processing technology of the continuous spiral baffle heat exchanger is relatively complicated and difficult to produce.

Contents of the invention

The purpose of the present invention is to address the shortcomings of the prior art, thereby providing a trapezoidal inclined baffle shell-and-tube heat exchanger with small flow resistance, high heat exchange efficiency and easy processing.

A shell-and-tube heat exchanger with trapezoidal inclined baffles, including a shell, heat exchange tubes, tube sheets, tie rods and multiple sets of trapezoidal baffles, and two adjacent sets of trapezoidal baffles are arranged orthogonally , each group includes at least two parallel trapezoidal baffles, the trapezoidal baffles are uniformly distributed with a number of holes corresponding to the heat exchange tubes, the heat exchange tubes pass through the holes, and the trapezoidal baffles The baffles are arranged obliquely; the trapezoidal baffles are fixed by pull rods, and the distances between various trapezoidal baffles are fixed by distance tubes.

Based on the above, the angle between the trapezoidal baffle and the heat exchange tube is , 20°≤ ≤70°.

Based on the above, each group includes two trapezoidal baffles, and the trapezoidal baffles are cut from the two ends of the long axis of the elliptical plate with a height of He Gaowei made of arcuate plates; where R is the radius of the shell, and the major axis of the elliptical plate is , the minor axis is 2R.

Based on the above, the distance between the quasi-trapezoidal baffles in each group is .

Based on the above, each group includes three trapezoidal baffles, and the trapezoidal baffles in the middle of each group are cut from the vertices at both ends of the long axis to a height of The bow-shaped plates are made; the trapezoidal baffles in the middle of each group are cut from the vertices of the two ends of the long axis of the elliptical plate with a height of He Gaowei made of arcuate plates; where R is the radius of the shell, and the major axis of the elliptical plate is , the minor axis is 2R.

Based on the above, the distance between the quasi-trapezoidal baffles in each group is .

Based on the above, two sets of alternate trapezoidal baffles are arranged in parallel or symmetrically.

Based on the above, the included angle between the heat exchange tube passing through the hole and the trapezoidal baffle is is 45°.

Compared with the prior art, the present invention has substantive characteristics and progress, specifically, the present invention has the following advantages:

1. The adjacent two sets of trapezoidal-like baffles are arranged orthogonally, so that the shell-side fluid flows in one direction after one set of trapezoidal-like baffles flows through the next set of trapezoidal-like inclined baffles. The flow plate flows in another direction. This continuous periodical change of the fluid flow direction enhances the mixing degree of the shell-side fluid, which has a significant disturbance effect on the shell-side fluid, increases the average flow velocity and turbulence of the shell-side fluid, and improves the At the same time, the oblique flow of the trapezoidal baffle reduces the flow resistance compared with the lateral flow of the bow baffle, and the pressure drop of the shell side is greatly reduced, and it overcomes the continuous spiral baffle in terms of processing and manufacturing. The disadvantage that the heat exchanger is not easy to process.

2. After the numerical simulation calculation of the heat exchanger, when the shell-side mass flow rate is 3.5kg/s-16kg/s, the pressure drop of the trapezoidal baffle heat exchanger of the present invention is lower than that of the bow-shaped baffle heat exchanger. Reduced by 24.7% to 36.6%, the heat transfer coefficient increased by 1.3% to 2.4%, and the heat transfer coefficient under the unit shell side pressure drop increased by 26.8% to 36.9%; compared with the continuous spiral baffle heat exchanger, the pressure drop is reduced by 23% %~32.9%, the heat transfer coefficient is reduced by 1.6%~2.1%, and the heat transfer coefficient under the unit shell side pressure drop is increased by 20.5%~30%. Therefore, the trapezoidal baffle heat exchanger of the present invention can effectively reduce the pressure drop, Improve heat transfer coefficient and comprehensive performance.

3. The adjacent two groups of trapezoidal baffles are arranged orthogonally. The trapezoidal baffles are fixed by tie rods. Support and position in the vertical and longitudinal positions to avoid damage to the heat exchanger due to vibration.

Description of drawings

FIG. 1 is a schematic diagram of the internal structure of the trapezoidal inclined baffle shell-and-tube heat exchanger in Embodiment 1.

Fig. 2 is a front view of a set of quasi-trapezoidal baffles.

Fig. 3 is a right side view of Fig. 2 .

FIG. 4 is a schematic structural diagram of the orthogonal arrangement of two adjacent sets of trapezoidal baffles in Embodiment 1. FIG.

FIG. 5 is a structural schematic diagram expressing the positional relationship of four consecutive sets of trapezoidal baffles in Example 1. FIG.

Figure 6 is a schematic diagram of the fabrication of a quasi-trapezoidal baffle.

FIG. 7 is a structural schematic diagram expressing the positional relationship of four consecutive sets of trapezoidal baffles in Example 2. FIG.

Fig. 8 is a schematic diagram of the internal structure of the trapezoidal inclined baffle shell-and-tube heat exchanger in Embodiment 3.

FIG. 9 is a schematic diagram of the flow state of the shell-side fluid in Embodiment 1 when it flows through a set of trapezoidal baffles.

In the figure: 1. heat exchange tubes; 2. similar trapezoidal baffles; 3. first-class bow-shaped plates; 4. second-class bow-shaped plates; 5. holes.

detailed description

The technical solutions of the present invention will be described in further detail below through specific implementation methods.

Example 1

This embodiment provides a shell-and-tube heat exchanger with trapezoidal inclined baffles, including a shell, heat exchange tubes 1, tube sheets, tie rods and trapezoidal baffles 2, as shown in Figures 1 to 5, adjacent Two sets of trapezoidal baffles 2 are arranged orthogonally, and the alternate two sets of trapezoidal baffles 2 are arranged in parallel, each group includes two parallel trapezoidal baffles 2, and the trapezoidal baffles 2 correspond to the The heat exchange tubes 1 are evenly distributed with several holes 5, the heat exchange tubes 1 are arranged through the holes 5, the trapezoidal baffles 2 are arranged obliquely, the trapezoidal baffles 2 and the heat exchange tubes 1 Angle =45°, the schematic diagram of the flow state when the shell-side fluid flows through a set of trapezoidal baffles 2, as shown in Figure 9, the shell-side fluid flows in one direction after a set of trapezoidal baffles 2 , after flowing through the next set of trapezoidal inclined baffles 2, it flows in another direction. This continuous and periodic change of the fluid flow direction enhances the mixing degree of the shell-side fluid, and has an obvious effect on the disturbance of the shell-side fluid. Increase the average flow velocity and turbulence degree of the shell-side fluid, and improve the heat transfer efficiency.

The trapezoidal baffles 2 are fixed by pull rods, and the distance between various trapezoidal baffles 2 is fixed by a distance tube. The pull rod passes through the fixed tube hole and snaps into the shell, and the pull rod is covered with a distance tube, and the distance tube is fixed on the pull rod by bolts, so that the heat exchange tube 1 can be adjusted in the horizontal and vertical positions. Support and position on the ground to avoid damage to the heat exchanger due to vibration.

The distance between the trapezoidal baffles 1 in each group is , as shown in Figure 6, the trapezoidal baffle 2 is cut from the two ends of the long axis by an elliptical plate with a height of The second type of arcuate plate 4 and the height is made of a class of arcuate plates 3, where R is the radius of the shell, and the major axis of the ellipse is , the minor axis is 2R; ensure that the shell fluid flows periodically under the guidance of the trapezoidal baffle 2 without leakage, and the oblique flow of the trapezoidal baffle 2 is compared with the transverse flow of the bow baffle The flow resistance is reduced, the shell side pressure drop is greatly reduced, and the disadvantage of continuous spiral baffle heat exchangers being difficult to process is overcome in terms of processing and manufacturing.

Example 2

As shown in Figure 7, the difference between this embodiment and Embodiment 1 is that two sets of alternate trapezoidal baffles 2 are arranged symmetrically;

Example 3

As shown in Figure 8, the difference between this embodiment and the above-mentioned embodiment is that each group includes three trapezoidal baffles 2, and the distance between the trapezoidal baffles 2 in each group is , the quasi-trapezoidal baffles 2 in the middle of each group are cut from the two ends of the long axis by elliptical plates, and the height is The bow-shaped plate is made; the quasi-trapezoidal baffle plate 2 in the middle of each group is cut from the two ends of the long axis of the elliptical plate with a height of He Gaowei made of a segmented plate, where R is the radius of the shell and the major axis of the ellipse is , the minor axis is 2R.

In other embodiments, the difference from the above embodiments lies in: the included angle between the trapezoidal baffle plate 2 and the heat exchange tube 1 Can be set according to needs.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: the present invention can still be The specific implementation mode of the invention is modified or some technical features are equivalently replaced; without departing from the spirit of the technical solution of the present invention, all of them shall be included in the scope of the technical solution claimed in the present invention.

Claims (8)

1. A shell-and-tube heat exchanger with trapezoidal inclined baffles, characterized in that: it includes a shell, heat exchange tubes, tube sheets, tie rods and multiple groups of trapezoidal baffles, and the adjacent two groups of the same type The trapezoidal baffles are arranged orthogonally, each group includes at least two parallel trapezoidal baffles, and the trapezoidal baffles are uniformly distributed with a number of holes corresponding to the heat exchange tubes, and the heat exchange tubes pass through the holes The trapezoidal-like baffles are arranged obliquely; the trapezoidal-like baffles are fixed by pull rods, and the distances between various trapezoidal baffles are fixed by distance tubes. 2. The shell-and-tube heat exchanger with trapezoidal inclined baffles according to claim 1, wherein the included angle between the trapezoidal baffles and the heat exchange tubes is , 20°≤ ≤70°. 3. The shell-and-tube heat exchanger with trapezoidal inclined baffles according to claim 2, characterized in that: each group includes two trapezoidal baffles, and the trapezoidal baffles are composed of elliptical plates from the length The heights of the two ends of the shaft are respectively cut off as He Gaowei made of arcuate plates; where R is the radius of the shell, and the major axis of the elliptical plate is , the minor axis is 2R. 4. The shell-and-tube heat exchanger with trapezoidal inclined baffles according to claim 3, wherein the distance between the trapezoidal baffles in each group is . 5. The shell-and-tube heat exchanger with trapezoidal inclined baffles according to claim 2, wherein each group includes three trapezoidal baffles, and the trapezoidal baffles in the middle of each group are formed from the length The heights of the vertices at both ends of the axis are respectively cut off as The bow-shaped plates are made; the trapezoidal baffles in the middle of each group are cut from the vertices of the two ends of the long axis of the elliptical plate with a height of He Gaowei made of arcuate plates; where R is the radius of the shell, and the major axis of the elliptical plate is , the minor axis is 2R. 6. The shell-and-tube heat exchanger with trapezoidal inclined baffles according to claim 5, wherein the distance between the trapezoidal baffles in each group is . 7. The shell-and-tube heat exchanger with trapezoidal inclined baffles according to any one of claims 2 to 6, characterized in that two sets of trapezoidal baffles are arranged in parallel or symmetrically. 8. The shell-and-tube heat exchanger with trapezoidal inclined baffles according to claim 7, wherein the heat exchange tube passes through the hole and forms an angle with the trapezoidal baffles is 45°.