Static mixer with crescent notch

Abstract

The invention belongs to the field of mixing and mass transfer reinforcement, relates to a static mixer with a crescent notch, and aims to improve the fluid mixing performance, reduce the equipment maintenance cost and prolong the service life. The mixer is composed of a pipe body and mixing units axially arranged at intervals in the pipe body, and the mixing units are arranged in a staggered mode at the staggered angle of 0-90 degrees. The mixing unit is of a multi-layer composite structure and is formed by staggering and overlapping at least three base layer groups, and each base layer group comprises a plurality of crescent notch tubular elements which are distributed along the radial direction. A plurality of rows of crescent notches are uniformly formed in the circumferential direction of the tubular element, an included angle of 0-45 degrees is formed between the long axis of each notch and the axis of the element, and the chord length is 0.1-0.6 time of the diameter of the element. Every two notches are oppositely arranged to form an asymmetric flow guide surface, and when fluid flows through the notches, alternating hairpin vortexes are formed and a periodic expansion-contraction effect is generated, so that the chaotic mixing characteristic is enhanced. The multi-layer notch array structure can reduce damage caused by fluid impact, and the service life of equipment is prolonged.

Description

Technical Field

[0001] The present invention belongs to the field of enhanced mixing and mass transfer, and particularly relates to a static mixer with a crescent-shaped notch. Background Art

[0002] A static mixer is a device that achieves efficient fluid mixing through a fixed internal structure design. Its core principle is to enhance the mixing and mass transfer process between different fluids through processes such as splitting, shearing, rotating, and recombining. In fields such as chemical engineering, energy, environmental protection, food, and pharmaceuticals, static mixers have become an important technical means for enhanced mixing and mass transfer due to their advantages of no moving parts, low energy consumption, high efficiency, and easy integration.

[0003] However, in chemical production, there is no linear positive correlation between the enhancement of mixing performance and the improvement of operating economy. When the mixing performance increases to a certain threshold, the damage caused by the impact of the fluid on the internal components of the pipeline becomes more severe, significantly reducing the service life of the pipeline and increasing the maintenance cost of the equipment, resulting in poor economy. The present invention has high mixing ability and a long-life design at the same time. Its design concept conforms to the mainstream trend of the current development of static mixer technology, promoting the development of the process industry towards high efficiency, cleanliness, and low carbon. Summary of the Invention

[0004] The object of this invention is to design a static mixer with a crescent-shaped notch, which can effectively improve the fluid mixing ability while reducing the equipment maintenance cost and increasing the service life of the static mixer.

[0005] To solve the above problems, the technical solutions provided by this invention are as follows:

[0006] The static mixer with a crescent-shaped notch is characterized in that a number of mixing units (2) are axially spaced inside its pipe body (1), and the distance between adjacent mixing units is 0.5 - 2 times the pipe diameter, and adjacent mixing units are staggered, and the stagger angle is 0 - 90°.

[0007] Furthermore, the mixing unit (2) is a multi-layer composite structure, and its basic layer group is composed of an array of n tubular elements (2-1) with crescent-shaped notches distributed radially. The number of tubular elements (2-1) satisfies n = D / (d + δ), (D: pipe body diameter, d: tubular element diameter, δ: gap between adjacent tubular elements, n is an integer). At least 3 basic layer groups are stacked with a stagger of 0 - 90°, and then annular cutting is performed along the axial direction of the tubular element (2-1) at an angle of 0 - 90° with the inner diameter of the pipe body (1) as the diameter to form the mixing unit (2).

[0008] The tubular element (2-1) is a circular tube with crescent-shaped notches (2-2) on its wall. The major axis of the crescent-shaped notch (2-2) forms an angle of 0 to 45° with the axis of the tubular element (2-1), and the chord length L of the crescent-shaped notch (2-2) is 0.1d to 0.6d.

[0009] Further, the tubular element (2-1) is provided with 4 rows of crescent-shaped notches (2-2) along the circumferential direction. The distance between adjacent notches (2-2) in the same row is 0.1L to 1L. The 4 rows of notches are arranged in pairs along the circumferential direction, and the adjacent two rows of notches are distributed by rotating 0 to 90° along the major axis of the notch.

[0010] The shape of the crescent-shaped notch can be one or a combination of new moon, crescent moon, half moon, and gibbous moon. The edge of the mixing unit fits the inner wall of the tube and is connected to the tube body by means such as welding.

[0011] Compared with the prior art, the present invention arranges a plurality of mixing units in the tube body. By changing the flow-facing angle of the mixing units in the tube body, a spiral flow can be formed in the tube body, enhancing the cutting and recombination effects on the fluid and improving the mixing and mass transfer efficiency between fluids.

[0012] The asymmetric flow guiding surface formed by the crescent-shaped notches arranged in pairs along the circumferential direction can cause many hairpin vortices with alternating directions to be formed when the fluid flows through the notches, strengthening the mixing performance of the fluid. Due to the different angular directions of the notches, the fluid will generate tangential velocity components with alternating directions and a periodic expansion-contraction effect when passing through the crescent-shaped notches, further enhancing the chaotic mixing characteristics of the fluid.

[0013] In the mixing unit, the array of multi-layer notch tubular elements forms a structure similar to a porous structure, which not only enables the fluid to be evenly mixed and increases the phase boundary area between fluids, but also can effectively disperse the shear force of the fluid on the crescent-shaped notch tubular element, thereby reducing the damage to the internal device of the mixer caused by impact, improving the service life, and reducing the manufacturing and maintenance costs. Description of the Drawings

[0014] Figure 1 is a schematic structural diagram of a static mixer with crescent-shaped notches;

[0015] Figure 2 is a schematic structural diagram of the mixing unit;

[0016] Figure 3 is a schematic structural diagram of a tubular element with crescent-shaped notches;

[0017] Figure 4 is a schematic diagram of the shape of a crescent-shaped notch perpendicular to the oncoming flow; Detailed Embodiments

[0018] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments:

[0019] A static mixer with a crescent-shaped notch includes the following parts: a pipe body, a mixing unit, a tubular element with a crescent-shaped notch, and a crescent-shaped notch.

[0020] Combined with Figure 1 , the crescent-shaped notch static mixer is composed of a number of mixing units arranged axially at intervals inside the pipe body.

[0021] The adjacent mixing units are arranged staggeredly at a stagger angle of 0 to 90°, and the distance between the mixing units is 0.5 to 2 times the pipe diameter. The number of mixing units, the diameter and length of the pipe body are designed according to actual working conditions as required.

[0022] Combined with Figure 2 , the mixing unit is a multi-layer composite structure, and its basic layer group is composed of an array of n tubular elements with crescent-shaped notches distributed radially. The number of tubular elements satisfies n = D / (d + δ), (D: pipe body diameter, d: tubular element diameter, δ: gap between adjacent tubular elements, n is an integer). At least 3 basic layer groups are superimposed after staggering 0 to 90° to form a mixing unit.

[0023] Combined with Figure 3 , the tubular element is a circular pipe with a crescent-shaped notch on the wall surface, and the major axis of the notch forms an angle of 0 to 45° with the axis of the tubular element. The chord length L of the crescent-shaped notch is 0.1d to 0.6d. The shape of the crescent-shaped notch can be crescent, crescent moon, half moon, convex moon.

[0024] Combined with Figure 3 , 4 rows of crescent-shaped notches are opened in the circumferential direction of the tubular element. The distance between adjacent notches in the same row is 0.1L to 1L. The 4 rows of notches are arranged in pairs in the circumferential direction, and the adjacent two rows of notches are distributed by rotating 0 to 90° along the major axis of the notch.

[0025] Combined with Figure 2 、 Figure 3 , the connection methods between the tubular elements in the basic layer group of the mixing unit and between multiple basic layer groups can adopt connection forms such as welding.

[0026] The connection between the pipe body and the mixing unit is achieved by cutting and grinding the edge of the mixing unit to make the edge of the mixing unit fit the inner wall of the pipe, and then welding the mixing unit to the pipe body.

[0027] In practical applications, in order to facilitate connection with other pipelines or equipment, the inlet and outlet connectors can use flange connections with bolts, or process V-shaped grooves at the ends of the pipe body for seamless butt joints, or also adopt direct welding connection methods.

[0028] Example 1:

[0029] In this example, the static mixer with crescent-shaped notches uses a DN100 steel pipe with a length of 1000 mm and a pipe wall thickness of 4 mm. The mixing unit is composed of 3 layers of basic layer groups that are stacked and welded after being staggered by 90°. The basic layer group is composed of 5 tubular elements that are welded together after being closely attached radially. The outer diameter of the crescent-shaped notch tubular element is 24 mm, and the wall thickness is 1 mm. There are 4 rows of semi-circular notches opened along the axial direction of the pipe, and the chord length L of the notch is 8 mm. The major axis of the notch forms a 45° angle with the axis of the tubular element. The adjacent notches in the same row are spaced 4 mm apart. The 4 rows of notches are arranged in pairs in the circumferential direction of the pipe, and the adjacent two rows of notches are distributed by rotating 90° along the major axis of the notch. A circular cut with a diameter of 100 mm is made along the 45° angle of the axial direction of the tubular element to form the mixing unit. 3 mixing units are placed at intervals along the axial direction of the pipe body, and the interval distance between the mixing units is 180 mm, and the adjacent mixing units are staggered, and the stagger angle is 90°.

[0030] Example 2:

[0031] The pipe body and the mixing unit used in this example are basically the same as those in Example 1. The difference is that the basic layer groups are stacked in parallel and a circular cut with a diameter of 100 mm is made along the 90° angle of the axial direction of the tubular element to form the mixing unit. In this example, since the ports of the tubular elements are closely attached to the pipe wall surface, the fluid can only flow in and out through the crescent-shaped notches, so the shearing effect on the fluid will be better. Therefore, the strengthening effect on mixing is particularly obvious under the "gas-gas" working condition.

Claims

1. The static mixer with crescent-shaped notch is characterized in that: A plurality of mixing units (2) are arranged in an axially spaced relationship inside the tube body (1), the spacing between adjacent mixing units being 0.5 to 2 times the tube diameter, and adjacent mixing units being arranged in a staggered manner with a staggered angle of 0 to 90 degrees. Furthermore, the mixing unit (2) is a multi-layer composite structure, wherein the basic layer group is composed of an array of n tubular elements (2-1) with crescent-shaped notches distributed in the radial direction, and the number of the tubular elements (2-1) satisfies n=D / (d+δ), (D: diameter of the tube body, d: diameter of the tubular element, δ: gap between adjacent tubular elements, n is an integer). At least three basic layer groups are staggered 0 to 90 degrees and then cut into a ring shape with the inner diameter of the tube body (1) as the diameter along the axial direction of the tubular element (2-1) at an angle of 0 to 90 degrees to form the mixing unit (2).

2. A static mixer with a crescent-shaped notch according to claim 1, characterized in that: The tubular element (2-1) is a circular tube with a crescent-shaped notch (2-2) on the wall, the long axis of the crescent-shaped notch (2-2) and the axis of the tubular element (2-1) form an angle of 0 to 45 degrees, and the chord length L of the crescent-shaped notch (2-2) is 0.1d to 0.6d. Furthermore, the tubular element (2-1) is provided with four rows of crescent-shaped slots (2-2) along the circumferential direction, the spacing between adjacent slots (2-2) in the same row is 0.1L to 1L, the four rows of slots are arranged opposite to each other in pairs along the circumferential direction, and the slots in two adjacent rows are distributed rotated 0 to 90 degrees along the long axis of the slots.

3. The static mixer with crescent-shaped notch is characterized in that: The shape of the crescent-shaped notch can be one or a combination of a new moon, a meniscus, a half moon, a convex moon, and the edge of the mixing unit is connected to the tube body (1) by welding or the like.

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