Inner rib type heat exchange device based on acoustic black holes and design method of inner rib type heat exchange device

Abstract

The invention relates to the technical field of heat exchange equipment, and provides an inner rib type heat exchange device based on acoustic black holes and a design method of the inner rib type heat exchange device. Wherein the tube body is an inner ribbed tube, at least three inner ribs are evenly distributed on the inner wall of the inner ribbed tube in the circumferential direction, each inner rib is of a one-dimensional acoustic black hole structure, and the thickness of each inner rib is decreased progressively according to the power function rule in the direction away from one tube end; the baffle plate and the pass partition plate are of a one-dimensional acoustic black hole structure or a two-dimensional acoustic black hole structure, and if the baffle plate and the pass partition plate are of the one-dimensional acoustic black hole structure, the thicknesses of the baffle plate and the pass partition plate are gradually decreased in the single direction. If the acoustic black hole structure is a two-dimensional acoustic black hole structure, the thickness of the acoustic black hole structure is gradually reduced along any direction from the central position of the acoustic black hole or is designed into a variable-curvature curved surface. According to the scheme, the acoustic black hole structure and the inner finned tube type heat exchange device are combined, so that the problems of heat exchange efficiency, vibration noise and the like existing in a traditional heat exchange device are solved at the same time.

Description

Technical Field

[0001] This invention relates to the field of heat exchange equipment technology, and in particular to an internal ribbed heat exchange device based on acoustic black holes and its design method. Background Technology

[0002] Heat exchangers are devices that transfer part of the heat from a hot fluid to a cold fluid. They play an important role in chemical, petroleum, power, food and many other industrial productions. In chemical production, heat exchangers can be used as heaters, coolers, condensers, evaporators and reboilers, and are widely used.

[0003] Enhanced heat transfer technology in heat exchangers is of great significance for energy conservation and consumption reduction. Among them, passive enhanced heat transfer technology, which achieves enhanced heat transfer without requiring external high-quality energy, is an important research direction. Utilizing excitation to induce vibration in heat exchange pipes to enhance heat transfer is a form of passive enhanced heat transfer. This transforms the strict prevention of fluid vibration-induced factors within the heat exchanger into the effective and rational utilization of vibration, significantly improving the efficiency of the heat exchanger. Furthermore, vibration inhibits the adhesion of scale and other impurities on the surface of the heat exchange pipes, reducing the thermal resistance of the fouling and achieving highly efficient composite enhanced heat transfer.

[0004] Internally finned tube heat exchangers are widely used in industrial heat exchange applications because the internal fins increase the heat exchange area and enhance fluid turbulence within the tube. However, traditional internally finned tube heat exchangers have the following drawbacks: 1. It is difficult to balance heat exchange and noise reduction: Although the internal ribs can improve heat exchange efficiency, turbulent noise is easily generated when the fluid flows around the internal ribs. In addition, the vibration of the tube bundle and plate structure (baffles, partitions, etc.) during the operation of the device will aggravate the noise and affect the working environment. 2. Vibration causes component damage: Long-term vibration can easily cause cracking of the weld between the inner rib and the tube sheet, fatigue fracture, and collision and wear between the baffle and the tube bundle, thus shortening the service life of the equipment; 3. Limited Structural Optimization: Existing internal rib designs only focus on "increasing area / disturbance" without considering vibration and noise control requirements. Adding additional vibration damping and noise reduction components (such as sound insulation cotton) will increase the size, weight, and cost of the device, and will not solve the root cause of vibration. Summary of the Invention

[0005] The purpose of this invention is to solve at least one technical problem in the background art and to provide an internal ribbed heat exchange device based on acoustic black holes and its design method.

[0006] To achieve the above objectives, the present invention provides an internally ribbed heat exchange device based on an acoustic black hole, comprising: a shell, a tube body, a tube sheet, an end cap, a baffle plate, and a partition plate; Multiple tubes are arranged in a parallel array in space, and two tube sheets are respectively set at both ends of the multiple tubes. Each tube sheet is arranged with through holes corresponding to the ends of each tube, and the two ends of each tube are sealed and connected to the corresponding through holes. Each of the baffles is provided with a tube hole for the tube body to pass through, and each baffle is installed on the inner wall of the shell at intervals and in an alternating manner to guide the flow of shell-side fluid; The tube sheet and the tube body are fixedly installed in the housing with openings at both ends, and the end caps cover the openings at both ends of the housing; The partition plate is disposed between one of the tube sheets and the corresponding end cap, dividing the space between the end cap and the tube sheet into two media chambers for guiding the flow of fluid in the tube. The top and bottom of the end cap are respectively provided with a refrigerant inlet and a refrigerant outlet relative to the partition plate. The top of one end of the shell is provided with a heat medium outlet near the refrigerant inlet and relative to the pipe body. The bottom of the other end of the shell is provided with a heat medium inlet relative to the pipe body. The tube body is an internally ribbed tube, and at least three internal ribs are evenly distributed along the circumference of the inner wall of the internally ribbed tube. The internal ribs are a one-dimensional acoustic black hole structure, and their thickness decreases in a power function manner along the direction away from one of the tube ends. The baffle and the partition plate are either one-dimensional acoustic black hole structures or two-dimensional acoustic black hole structures. If it is a one-dimensional acoustic black hole structure, its thickness decreases along a single direction; if it is a two-dimensional acoustic black hole structure, its thickness decreases from the center of the acoustic black hole along any direction or is designed as a variable curvature surface.

[0007] According to one aspect of the invention, the thickness expression of the inner rib is as follows: ,in, x is a constant, x1 is the distance from a point on one surface of the inner rib to the tip of its acoustic black hole region. When x reaches its maximum value, h(x) = h0, h0 is the thickness of the uniform thickness region of the inner rib, m1 is a power exponent and m1≥2, and the thickness of the tip of the acoustic black hole region of the inner rib approaches zero.

[0008] According to one aspect of the invention, if the baffle and the partition plate are one-dimensional acoustic black hole structures, the thickness of the baffle and the partition plate is proportional to the thickness of the baffle along a single direction. Decreasing, of which, x3 is a constant, x3 is the distance from a point on a surface of the baffle or partition plate to the thinnest point in its acoustic black hole region, and m3 is a power exponent. ; If it is a two-dimensional acoustic black hole structure, the thickness of the baffle and the partition plate is proportional to the fluid flow direction and the tube arrangement direction. Decreasing, of which, x2 is a constant, x2 is the distance from a point on one surface of the baffle or splitter plate to the thinnest point of its acoustic black hole region, and y is the perpendicular distance from that point to another surface. m2 is a power exponent and m2≥2; r c Rc is the cutoff radius of the acoustic black hole, and r0 is the radius of the acoustic black hole region; or it can be designed as a variable curvature surface.

[0009] According to one aspect of the invention, the number of inner ribs is 3-12, which are evenly spaced on the wall of the inner rib tube. The thickness of the starting end of the inner rib is 0.5-1.5 mm, and the minimum thickness of the tip of the acoustic black hole region of the inner rib is 0.05-0.1 mm.

[0010] According to one aspect of the present invention, the baffle is a two-dimensional acoustic black hole structure with variable thickness or variable thickness + variable curvature design; the partition is a one-dimensional acoustic black hole structure with the thickness decreasing along the fluid turning direction, and the decreasing length is 1 / 3 to 1 / 2 of the total length of the partition.

[0011] According to one aspect of the invention, the root surface of the inner rib of the one-dimensional acoustic black hole structure is provided with a transition rounded corner, and the edges of the baffle and the partition of the two-dimensional acoustic black hole are provided with an arc transition.

[0012] According to one aspect of the invention, the inner rib tube is made of copper alloy or stainless steel.

[0013] To achieve the above objectives, the present invention also provides a design method for an internally finned heat exchanger based on an acoustic black hole, used to design the aforementioned heat exchanger, comprising: S1: Determine operating parameters: Obtain the type, temperature range, pressure range, and flow rate requirements of the tube-side and shell-side fluids, and clarify the heat exchange power target and noise control requirements; S2: Design parameters of the inner ribs of a one-dimensional acoustic black hole: Determine the number and spacing of the inner ribs based on the diameter of the tube body, determine the power exponent based on the fluid viscosity and the inner rib material, and determine the starting end thickness and the minimum end thickness in combination with the processing technology. S3: Design of acoustic black hole structure types for baffles and partitions: If the shell-side fluid velocity is ≤1.5m / s, the baffle adopts a two-dimensional acoustic black hole structure with variable thickness and variable curvature; if the shell-side fluid velocity is >1.5m / s, the baffle adopts a two-dimensional acoustic black hole structure with variable thickness; if the tube-side pressure drop requirement is ≤0.3MPa, the partition adopts a one-dimensional acoustic black hole structure. S4: Multiphysics simulation verification: heat transfer efficiency is calculated through CFD simulation, and vibration modes and noise values ​​are analyzed through finite element simulation. S5: Prototype Manufacturing and Testing: Fabricate the inner rib tubes, baffles, and partition plates according to the design parameters and black hole structure type. After assembling the heat exchange device based on the design structure, conduct performance testing. If the performance does not meet the standards, return to steps S2 and S3 to adjust the parameters and black hole structure type respectively.

[0014] According to one aspect of the present invention, in step S2, the length L of the inner rib satisfies L=l1+l2, where l1 is the length of the acoustic black hole segment, l2 is the length of the equal-thickness segment, L is consistent with the effective heat transfer length of the inner rib tube, and the thickness of the equal-thickness segment is the same as the thickness h0 at the starting end of the inner rib.

[0015] According to one aspect of the present invention, the CFD simulation adopts the RNG turbulence model, the finite element simulation adopts the modal superposition method to calculate the vibration response, and the noise simulation adopts the boundary element method to calculate the sound pressure level.

[0016] According to the solution of the present invention, the following beneficial effects can be obtained compared with the prior art: 1. Significantly improved heat exchange efficiency: The variable thickness structure of the inner rib of the one-dimensional acoustic black hole further divides the flow channel inside the pipe, and together with the two-dimensional acoustic black hole, it achieves the vibration energy accumulation effect at different locations, strengthens the fluid turbulence disturbance, and increases the heat exchange area to improve heat exchange efficiency. 2. Effective vibration and noise control: The acoustic black hole structure can concentrate and dissipate vibration energy, reduce the operating noise of the device, and easily meet industrial noise standards; 3. Extended equipment lifespan: The vibration reduction design reduces the collision and wear between the tube bundle and the plate structure, which can significantly reduce the risk of weld cracking and extend the equipment lifespan; 4. Significant cost advantage: No external vibration damping and noise reduction components are required. The acoustic black hole design of the internal ribs, baffles, and partition plates can be achieved through existing processes, resulting in only a small increase in manufacturing costs, which is far lower than the cost of "ordinary heat exchangers + vibration damping and noise reduction components". Attached Figure Description

[0017] Figure 1 A schematic perspective view of an internally ribbed heat exchange device based on an acoustic black hole according to an embodiment of the present invention. Figure 2 A schematic diagram illustrating the arrangement of tube sheet and tube body structures according to one embodiment of the present invention; Figure 3 A schematic perspective view of a tube according to an embodiment of the present invention; Figure 4 A schematic perspective view of an inner rib according to an embodiment of the present invention; Figure 5 A schematic cross-sectional view of the inner rib portion according to an embodiment of the present invention; Figure 6A schematic perspective view of a baffle plate according to an embodiment of the present invention; Figure 7 A schematic front view of a baffle plate according to an embodiment of the present invention; Figure 8 A schematic cross-sectional view of a baffle plate according to an embodiment of the present invention is shown. Figure 9 A schematic front view of a tube sheet according to an embodiment of the present invention; Figure 10 The schematic diagram shows a front view of a partition plate according to an embodiment of the present invention. Detailed Implementation

[0018] The invention will now be discussed with reference to exemplary embodiments. It should be understood that the described embodiments are merely intended to enable those skilled in the art to better understand and thus implement the invention, and are not intended to imply any limitation on the scope of the invention.

[0019] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment".

[0020] Figure 1 A schematic perspective view of an internally ribbed heat exchange device based on an acoustic black hole according to an embodiment of the present invention. Figure 2 A schematic diagram illustrating the arrangement of tube sheet and tube body structures according to one embodiment of the present invention; Figure 3 A schematic perspective view of a tube according to an embodiment of the present invention; Figure 4 A schematic perspective view of an inner rib according to an embodiment of the present invention; Figure 5 A schematic cross-sectional view of the inner rib portion according to an embodiment of the present invention; Figure 6 A schematic perspective view of a baffle plate according to an embodiment of the present invention; Figure 7 A schematic front view of a baffle plate according to an embodiment of the present invention; Figure 8 A schematic cross-sectional view of a baffle plate according to an embodiment of the present invention is shown. Figure 9 A schematic front view of a tube sheet according to an embodiment of the present invention; Figure 10 This schematic diagram shows a front view of a partition plate according to one embodiment of the present invention. Figures 1-10 As shown, in this embodiment, an internally ribbed heat exchange device based on an acoustic black hole includes: a shell 1, a tube body 2, a tube sheet 3, a head 4, a baffle plate 5, and a partition plate 6. Multiple tube bodies 2 are arranged in a parallel spatial array, and two tube sheets 3 are respectively set at both ends of the multiple tube bodies 2. Each tube sheet 3 is arranged with through holes 7 corresponding to the ends of each tube body 2, and the two ends of each tube body 2 are sealed and connected to the corresponding through holes 7. Multiple baffles 5 are provided with pipe holes 8 for the tube body 2 to pass through. Each baffle 5 is installed on the inner wall of the shell 1 at intervals and in an alternating manner to guide the flow of shell-side fluid. The tube sheet 3 and the tube body 2 are fixedly installed in the shell 1 which has openings at both ends, and the end caps 4 cover the openings at both ends of the shell 1; The partition plate 6 is disposed between one of the tube sheets 3 and the corresponding end cap 4, dividing the space between the end cap 4 and the tube sheet 3 into two media chambers for guiding the flow of tube-side fluid; The top and bottom of the end cap 4 are respectively provided with a refrigerant inlet 9 (for pipe-side fluid) and a refrigerant outlet 10 (for pipe-side fluid) relative to the partition plate 6. The top of one end of the shell 1 is near the refrigerant inlet 9 and is provided with a heat medium outlet 11 (for shell-side fluid) relative to the pipe body 2. The bottom of the other end of the shell 1 is provided with a heat medium inlet 12 (for shell-side fluid) relative to the pipe body 2. like Figure 3 , Figure 4 and Figure 5 As shown, in this embodiment, the tube body 2 is an inner rib tube, and at least three inner ribs 13 are evenly distributed along the circumferential direction on the inner wall of the inner rib tube. The inner ribs 13 are one-dimensional acoustic black hole structures, and their thickness decreases in a power function law along the direction away from one of the tube ends. like Figure 6 , Figure 7 , Figure 8 and Figure 10 As shown, in this embodiment, the baffle 5 and the partition 6 are either one-dimensional acoustic black hole structures or two-dimensional acoustic black hole structures. If it is a one-dimensional acoustic black hole structure, its thickness decreases along a single direction; if it is a two-dimensional acoustic black hole structure, its thickness decreases along any direction from the center of the acoustic black hole or is designed as a variable curvature surface.

[0021] The above configuration allows the inner rib tube, which incorporates a one-dimensional acoustic black hole structure, to absorb structural vibrations and enhance fluid disturbances. The baffles and partitions of the one-dimensional or two-dimensional acoustic black hole structure can absorb the vibration energy of the tube and shell and transfer it to the fluid, thereby enhancing fluid disturbances and increasing the heat exchange area and improving heat exchange efficiency.

[0022] Furthermore, according to one embodiment of the present invention, the thickness expression of the inner rib is as follows: ,in, x is a constant, and x1 is one surface of the inner rib ( Figure 3 and Figure 4 A point on the bottom surface of the black hole (from the tip of its acoustic black hole region) to the tip of its acoustic black hole region ( Figure 3and Figure 4 The distance from the left endpoint (i.e., the thinnest point in the acoustic black hole region) is such that when x reaches its maximum value, h(x) = h0, where h0 is the uniform thickness region of the inner rib ( Figure 3 and Figure 4 The thickness of the maximum thickness region in the middle is m1, which is a power exponent and m1≥2. The thickness of the acoustic black hole region tip of the inner rib approaches zero.

[0023] Furthermore, according to one embodiment of the present invention, if the baffle 5 and the partition plate 6 are one-dimensional acoustic black hole structures, their thickness is such that... Decreasing, of which, x3 is a constant, and x3 is one surface of the baffle or partition plate. Figure 6 The bottom surface of the baffle or Figure 1 The distance from a point on the bottom surface of the mid-section partition to the thinnest point of its acoustic black hole region, m3 being a power exponent. ; If it is a two-dimensional acoustic black hole structure, the thickness of the baffle 5 and the partition plate 6 is along the fluid flow direction and the tube arrangement direction according to... Decreasing, of which, x2 is a constant, and x2 is one surface of the baffle or splitter plate. Figure 6 The bottom surface of the baffle or Figure 1 The distance from a point on the bottom surface of the middle partition to the thinnest point in its acoustic black hole region, and y is the perpendicular distance from that point to another surface; m2 is a power exponent and m2≥2; r c r0 is the cutoff radius of the acoustic black hole and r0 is the radius of the acoustic black hole region; or vibration energy can be concentrated and fluid disturbance can be enhanced through the design of a variable curvature surface (the curvature of the surface increases along the fluid direction).

[0024] In this embodiment, there are 3-12 inner ribs, which are evenly spaced on the wall of the inner rib tube. The thickness of the starting end of the inner rib is 0.5-1.5mm, and the thickness of the tip of the acoustic black hole region of the inner rib is close to zero. The actual minimum thickness is 0.05-0.1mm (to avoid processing breakage). At the same time, the root of the inner rib of the one-dimensional acoustic black hole structure (the side that contacts the wall of the inner rib tube) is provided with a transition radius of 0.1-0.3mm. This setting can effectively reduce the fluid flow resistance and avoid stress concentration.

[0025] In this embodiment, the baffle 5 is disposed within the shell to guide the shell-side fluid to laterally scour the tube 2. The baffle 5 is a two-dimensional acoustic black hole structure, employing a variable thickness or variable thickness + variable curvature design, with a maximum thickness of 5-10 mm and a minimum thickness of 0.1-0.3 mm. The partition plate 6 is a one-dimensional acoustic black hole structure, with its thickness decreasing along the fluid turning direction. The decreasing length is 1 / 3-1 / 2 of the total length of the partition plate, reducing vibration and impact during fluid turning. The edges of the baffle 5 of the two-dimensional acoustic black hole have rounded transitions to reduce fluid resistance and stress concentration.

[0026] Furthermore, according to one embodiment of the present invention, the inner ribbed tube is made of copper alloy (T2 / T3 copper, H62 brass) or stainless steel (304 / 316L). The shell is made of stainless steel, and the inner diameter is determined according to the number of tubes (usually 100-500mm); the tube sheet is made of forged steel with a thickness of 20-40mm, and is fixed to the inner ribbed tube by expansion joint and welding to ensure sealing performance.

[0027] The internal finned heat exchange device based on acoustic black holes according to the present invention can achieve the following beneficial effects compared with the prior art: 1. Significantly improved heat exchange efficiency: The variable thickness structure of the inner rib of the one-dimensional acoustic black hole further divides the flow channel inside the pipe, and together with the two-dimensional acoustic black hole, it achieves the vibration energy accumulation effect at different locations, strengthens the fluid turbulence disturbance, and increases the heat exchange area to improve heat exchange efficiency. 2. Effective vibration and noise control: The acoustic black hole structure can concentrate and dissipate vibration energy, reduce the operating noise of the device, and easily meet industrial noise standards; 3. Extended equipment lifespan: The vibration reduction design reduces the collision and wear between the tube bundle and the plate structure, which can significantly reduce the risk of weld cracking and extend the equipment lifespan; 4. Significant cost advantage: No external vibration damping and noise reduction components are required. The acoustic black hole design of the internal ribs, baffles, and partition plates can be achieved through existing processes, resulting in only a small increase in manufacturing costs, which is far lower than the cost of "ordinary heat exchangers + vibration damping and noise reduction components".

[0028] Furthermore, to achieve the above objectives, the present invention also provides a design method for an internally ribbed heat exchanger based on an acoustic black hole, used to design the aforementioned heat exchanger, comprising: S1: Determine operating parameters: Obtain the type (physical properties, including viscosity, thermal conductivity, density), temperature range, pressure range, and flow requirements of the tube-side and shell-side fluids, and clarify the heat exchange power target and noise control requirements; S2: Design parameters of the inner ribs of the one-dimensional acoustic black hole: Determine the number of inner ribs (6-8 for inner diameter 8-15mm, 10-12 for 15-25mm) and the spacing between inner ribs (3-8mm) based on the pipe diameter of the tube. Avoid excessively small spacing which can lead to scaling. Determine the power exponent based on the fluid viscosity and the inner rib material. Combine the processing technology to determine the thickness at the beginning and the minimum thickness at the end. In this embodiment, when the low-frequency vibration noise is large, the power exponent is 3-4 to enhance energy concentration and achieve broadband vibration reduction. When the vibration noise energy is concentrated in the mid-to-high frequency range, the power exponent is 2, resulting in less reflection at the edge of the acoustic black hole and lower processing difficulty. In this embodiment, the thickness expression of the inner rib is: ,in, x is a constant, and x1 is one surface of the inner rib ( Figure 3 and Figure 4 A point on the bottom surface of the black hole (from the tip of its acoustic black hole region) to the tip of its acoustic black hole region ( Figure 3 and Figure 4 The distance from the left endpoint (i.e., the thinnest point in the acoustic black hole region) is such that when x reaches its maximum value, h(x) = h0, where h0 is the uniform thickness region of the inner rib ( Figure 3 and Figure 4 The thickness of the region with the maximum thickness in the middle is m1, where m1 is a power exponent and m1≥2, and the thickness of the acoustic black hole region tip of the inner rib approaches zero. The length L of the inner rib satisfies L = l1 + l2, ​​where l1 is the length of the acoustic black hole section, l2 is the length of the equal-thickness section, L is consistent with the effective heat transfer length of the inner rib tube, and the thickness of the equal-thickness section is the same as the thickness h0 at the beginning of the inner rib. That is, the total length of the inner rib is consistent with the effective heat transfer length of the inner rib tube (usually 500-20000mm), divided into the "acoustic black hole section" (10-20mm, with decreasing thickness) and the "equal-thickness section" (the remaining length, thickness = h0), ensuring that the effective heat transfer area does not decrease.

[0029] S3: Design of acoustic black hole structure types for baffles and partitions: If the shell-side fluid velocity is ≤1.5m / s, the baffle adopts a two-dimensional acoustic black hole structure with variable thickness and variable curvature to enhance fluid disturbance; if the velocity is >1.5m / s, the baffle adopts only a two-dimensional acoustic black hole structure with variable thickness to avoid excessive pressure drop; if the tube-side pressure drop requirement is ≤0.3MPa, the partition adopts a one-dimensional acoustic black hole structure; the length of the partition is determined according to the number of tube passes (2-4 passes), and the length of the decreasing section of the one-dimensional acoustic black hole is 10-15mm to ensure smooth fluid diversion.

[0030] In this embodiment, if the baffle 5 and the partition plate 6 are one-dimensional acoustic black hole structures, their thickness is determined along a single direction (fluid direction) according to... Decreasing, of which, x3 is a constant, and x3 is one surface of the baffle or partition plate. Figure 6The bottom surface of the baffle or Figure 1 The distance from a point on the bottom surface of the mid-section partition to the thinnest point of its acoustic black hole region, m3 being a power exponent. ; If it is a two-dimensional acoustic black hole structure, the thickness of the baffle 5 and the partition plate 6 is along the fluid flow direction and the tube arrangement direction according to... Decreasing, of which, x2 is a constant, and x2 is one surface of the baffle or splitter plate. Figure 6 The bottom surface of the baffle or Figure 1 The distance from a point on the bottom surface of the middle partition to the thinnest point in its acoustic black hole region, and y is the perpendicular distance from that point to another surface; m2 is a power exponent and m2≥2; r c r0 is the cutoff radius of the acoustic black hole and r0 is the radius of the acoustic black hole region; or vibration energy can be concentrated and fluid disturbance can be enhanced through variable curvature surface design (the curvature of the surface increases along the fluid direction); The baffle 5 is a two-dimensional acoustic black hole structure with a maximum thickness of 5-10 mm and a minimum thickness of 0.1-0.3 mm. The partition plate 6 is a one-dimensional acoustic black hole structure with a thickness that decreases along the fluid turning direction. The decreasing length is 1 / 3 to 1 / 2 of the total length of the partition plate, reducing vibration and impact during fluid turning. The edges of the baffle 5 of the two-dimensional acoustic black hole have rounded transitions to reduce fluid resistance and stress concentration.

[0031] S4: Multiphysics simulation verification: heat transfer efficiency is calculated through CFD simulation, and vibration modes and noise values ​​are analyzed through finite element simulation. In this embodiment, CFD software (such as Fluent) is used, and the RNG (k-ε) turbulence model is selected to calculate the tube-side / shell-side heat transfer coefficient, which is required to be ≥10% higher than that of ordinary internally finned tubes. Finite element software (such as ANSYS) is used to calculate the vibration response of the tube bundle and plate structure through modal superposition method (the resonant frequency avoids the operating frequency ±10%), and the sound pressure level is calculated by combining the boundary element method (it should be ≤85dB). It is ensured that the tube-side pressure drop is ≤0.3MPa and the shell-side pressure drop is ≤0.2MPa to avoid exceeding the head of the delivery pump.

[0032] S5: Prototype Manufacturing and Testing: Fabricate the inner rib tubes, baffles, and partition plates according to the design parameters and black hole structure type. After assembling the heat exchange device based on the design structure, conduct performance testing. If the performance does not meet the standards, return to steps S2 and S3 to adjust the parameters and black hole structure type respectively.

[0033] In this embodiment, a cold rolling forming process (one-dimensional acoustic black hole inner ribs are extruded through a special mold) is used to ensure that the thickness tolerance is ≤ ±0.05mm; a milling process is used to process the variable thickness structure, followed by a polishing process (surface roughness Ra≤1.6μm); the assembly is carried out according to the conventional internal rib tube heat exchanger assembly process, and the heat exchange efficiency and noise value are tested. If the standards are not met, the process returns to steps S2 and S3 to adjust the parameters and black hole structure type respectively.

[0034] The heat exchange device designed according to the above-described design method of the acoustic black hole-based internal finned heat exchange device of the present invention can achieve the following beneficial effects compared with the prior art: 1. Significantly improved heat exchange efficiency: The variable thickness structure of the inner rib of the one-dimensional acoustic black hole further divides the flow channel inside the pipe, and together with the two-dimensional acoustic black hole, it achieves the vibration energy accumulation effect at different locations, strengthens the fluid turbulence disturbance, and increases the heat exchange area to improve heat exchange efficiency. 2. Effective vibration and noise control: The acoustic black hole structure can concentrate and dissipate vibration energy, reduce the operating noise of the device, and easily meet industrial noise standards; 3. Extended equipment lifespan: The vibration reduction design reduces the collision and wear between the tube bundle and the plate structure, which can significantly reduce the risk of weld cracking and extend the equipment lifespan; 4. Significant cost advantage: No external vibration damping and noise reduction components are required. The acoustic black hole design of the internal ribs, baffles, and partition plates can be achieved through existing processes, resulting in only a small increase in manufacturing costs, which is far lower than the cost of "ordinary heat exchangers + vibration damping and noise reduction components".

[0035] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely one preferred embodiment of the invention and are only used to explain the invention. They do not limit the scope of protection of the invention. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0036] Example 1 like Figure 1 As shown, this embodiment provides an internally ribbed heat exchanger based on an acoustic black hole, including a shell 1, a tube body 2, a tube sheet 3, an end cap 4, a baffle plate 5, and a partition plate 6, which are assembled into one unit in the order of shell 1-baffle plate 5-tube body 2-tube sheet 3-partition plate 6-end cap 4. The tube body 2 passes through a through hole in the tube sheet 3 and is fixed inside the shell. The end cap 4 is sealed to the outside of the tube sheet. The baffle plate 5 and the partition plate 6 are disposed inside the shell to guide the flow of fluid in the tube side and the shell side.

[0037] In this embodiment, the fluid in the inner pipe of pipe 2 is diesel engine cooling water (water + ethylene glycol, volume ratio 1:1), with an inlet temperature of 85 degrees Celsius, an outlet temperature of 65 degrees Celsius, a pressure of 1 MPa, and a flow rate of 15 m³ / s. 3 / h.

[0038] The shell-side fluid inside shell 1 is industrial circulating water, with an inlet temperature of 30 degrees Celsius, an outlet temperature of 40 degrees Celsius, a pressure of 0.4 MPa, and a flow rate of 25 m³ / s. 3 / h.

[0039] Tube 2 is an internally ribbed tube made of T2 copper, with an inner diameter of 16mm and a wall thickness of 1.5mm. It contains 8 internal ribs spaced 5mm apart. The internal ribs form a one-dimensional acoustic black hole structure with a power of 2. The initial thickness h0 = 1.0mm, the length of the acoustic black hole segment is 15mm, and the truncated thickness is 0.05mm. The thickness expression is... for.

[0040] The baffle 5 is made of H62 brass, with a diameter of 300mm (fitting a housing inner diameter of 320mm), and adopts a two-dimensional acoustic black hole structure. Its thickness is expressed as follows: ,in, r c R0 is the cutoff radius of the acoustic black hole, and r0 is the radius of the acoustic black hole region.

[0041] The partition plate 6 is made of forged steel, 200mm in length and 8mm in thickness. The decreasing section is 12mm long and adopts a one-dimensional acoustic black hole structure; its thickness is expressed as follows: , m3≥2.

[0042] The inner rib tube is formed by cold rolling, and the one-dimensional acoustic black hole inner rib is extruded through a special spiral die. After annealing (350 degrees Celsius, 1 hour) to soften it, the thickness tolerance of the inner rib is ensured to be ±0.03mm.

[0043] The baffle plate 5 is a two-dimensional variable thickness structure machined by a five-axis milling machine and then electrolytically polished.

[0044] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this application.

[0045] It should be understood that the sequence number of each step in the invention and its embodiments does not absolutely imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

Claims

1. An internally finned heat exchanger based on an acoustic black hole, comprising: Shell, tube body, tube sheet, end caps, baffles and partition plates; Multiple tubes are arranged in a parallel array in space, and two tube sheets are respectively set at both ends of the multiple tubes. Each tube sheet is arranged with through holes corresponding to the ends of each tube. The two ends of each tube are sealed and connected to the corresponding through holes. Each of the baffles is provided with a tube hole for the tube body to pass through, and each baffle is installed on the inner wall of the shell at intervals and in an alternating manner to guide the flow of shell-side fluid; The tube sheet and the tube body are fixedly installed in the housing with openings at both ends, and the end caps cover the openings at both ends of the housing; The partition plate is disposed between one of the tube sheets and the corresponding end cap, dividing the space between the end cap and the tube sheet into two media chambers for guiding the flow of fluid in the tube. The top and bottom of the end cap are respectively provided with a refrigerant inlet and a refrigerant outlet relative to the partition plate. The top of one end of the shell is provided with a heat medium outlet near the refrigerant inlet and relative to the pipe body. The bottom of the other end of the shell is provided with a heat medium inlet relative to the pipe body. The tube is characterized in that it is an internally ribbed tube, and at least three internal ribs are evenly distributed along the circumferential direction on the inner wall of the internally ribbed tube. The internal ribs are one-dimensional acoustic black hole structures, and their thickness decreases in a power function manner along the direction away from one of the tube ends. The baffle and the partition plate are either one-dimensional acoustic black hole structures or two-dimensional acoustic black hole structures. If it is a one-dimensional acoustic black hole structure, its thickness decreases along a single direction; if it is a two-dimensional acoustic black hole structure, its thickness decreases along any direction from the center of the acoustic black hole or is designed as a variable curvature surface.

2. The internal finned heat exchanger based on an acoustic black hole according to claim 1, characterized in that, The thickness expression of the inner rib is as follows: ,in, x is a constant, x1 is the distance from a point on one surface of the inner rib to the tip of its acoustic black hole region. When x reaches its maximum value, h(x) = h0, h0 is the thickness of the uniform thickness region of the inner rib, m1 is a power exponent and m1≥2, and the thickness of the tip of the acoustic black hole region of the inner rib approaches zero.

3. The internal finned heat exchanger based on an acoustic black hole according to claim 1, characterized in that, If the baffle and the partition plate are one-dimensional acoustic black hole structures, the thickness of the baffle and the partition plate is proportional to the thickness of the baffle along a single direction. Decreasing, of which, x3 is a constant, x3 is the distance from a point on a surface of the baffle or partition plate to the thinnest point in its acoustic black hole region, and m3 is a power exponent. ; If it is a two-dimensional acoustic black hole structure, the thickness of the baffle and the partition plate is proportional to the fluid flow direction and the tube arrangement direction. Decreasing, of which, x2 is a constant, x2 is the distance from a point on one surface of the baffle or splitter plate to the thinnest point of its acoustic black hole region, and y is the perpendicular distance from that point to another surface. m2 is a power exponent and m2≥2; r c Rc is the cutoff radius of the acoustic black hole, and r0 is the radius of the acoustic black hole region; or it can be designed as a variable curvature surface.

4. The internal finned heat exchanger based on an acoustic black hole according to claim 1, characterized in that, The number of inner ribs is 3-12, and they are evenly spaced on the wall of the inner rib tube. The thickness of the starting end of the inner rib is 0.5-1.5mm, and the minimum thickness of the tip of the acoustic black hole region of the inner rib is 0.05-0.1mm.

5. The internal finned heat exchanger based on an acoustic black hole according to claim 1, characterized in that, The baffle is a two-dimensional acoustic black hole structure with variable thickness or variable thickness + variable curvature design; the partition is a one-dimensional acoustic black hole structure with thickness decreasing along the fluid turning direction, and the decreasing length is 1 / 3 to 1 / 2 of the total length of the partition.

6. The internal finned heat exchanger based on an acoustic black hole according to claim 1, characterized in that, The root surface of the inner rib of the one-dimensional acoustic black hole structure is provided with a transition rounded corner, and the edges of the baffle and the partition of the two-dimensional acoustic black hole are provided with an arc transition.

7. The internal finned heat exchanger based on an acoustic black hole according to claim 1, characterized in that, The inner rib tube is made of copper alloy or stainless steel.

8. A design method for an internally finned heat exchanger based on an acoustic black hole, used to design the heat exchanger according to any one of claims 1-6, characterized in that, include: S1: Determine operating parameters: Obtain the type, temperature range, pressure range, and flow rate requirements of the tube-side and shell-side fluids, and clarify the heat exchange power target and noise control requirements; S2: Design parameters of the inner ribs of a one-dimensional acoustic black hole: Determine the number and spacing of the inner ribs based on the diameter of the tube body, determine the power exponent based on the fluid viscosity and the inner rib material, and determine the starting end thickness and the minimum end thickness in combination with the processing technology. S3: Design of acoustic black hole structure types for baffles and partitions: If the shell-side fluid velocity is ≤1.5m / s, the baffle adopts a two-dimensional acoustic black hole structure with variable thickness and variable curvature; if the shell-side fluid velocity is >1.5m / s, the baffle adopts a two-dimensional acoustic black hole structure with variable thickness; if the tube-side pressure drop requirement is ≤0.3MPa, the partition adopts a one-dimensional acoustic black hole structure. S4: Multiphysics simulation verification: heat transfer efficiency is calculated through CFD simulation, and vibration modes and noise values ​​are analyzed through finite element simulation. S5: Prototype Manufacturing and Testing: Process the inner rib tubes, baffles, and partition plates according to the design parameters and black hole structure type. After assembling the heat exchange device based on the design structure, conduct performance testing. If the performance does not meet the standards, return to steps S2 and S3 to adjust the parameters and black hole structure type respectively.

9. The design method of the internal finned heat exchanger based on acoustic black holes according to claim 8, characterized in that, In step S2, the length L of the inner rib satisfies L=l1+l2, where l1 is the length of the acoustic black hole segment, l2 is the length of the equal-thickness segment, L is consistent with the effective heat transfer length of the inner rib tube, and the thickness of the equal-thickness segment is the same as the thickness h0 at the starting end of the inner rib.

10. The design method of the internal finned heat exchanger based on acoustic black holes according to claim 8, characterized in that, The CFD simulation uses the RNG turbulence model, the finite element simulation uses the modal superposition method to calculate the vibration response, and the noise simulation uses the boundary element method to calculate the sound pressure level.

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