Self-adaptive flow distribution method and device for double-pipe heat exchanger

Abstract

The invention relates to the technical field of heat conversion flow distribution, in particular to a self-adaptive flow distribution method and device for a double-pipe heat exchanger, and the method comprises the following steps: S1, equipment assembly: installing a plurality of groups of flow pipes in the middle of a shell, and installing two groups of flow adjusting assemblies on one side of the input end of each of the plurality of groups of flow pipes; s2, arranging a plurality of groups of flow tubes in the shell in an annular matrix or a square matrix, establishing a plane-coordinate system by taking the center of the matrix as a coordinate origin, and numbering and marking each flow tube; s3, flow grade judgment; according to the scheme, the flow grade of the flow pipe is determined, the higher the flow grade is, the faster the flow speed is and the larger the flow is, then the flow channel area of the high-grade flow pipe is adjusted to decelerate and reduce the flow, the redundant quantity is distributed to the low-grade flow pipe, and it is guaranteed that the flow speed and the flow difference value of all the flow pipes are smaller than the set threshold value through comprehensive adjustment. Therefore, the effect of reasonable flow distribution is achieved, and the thermal conversion efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of heat conversion flow distribution technology, and particularly to an adaptive flow distribution method and apparatus for shell-and-tube heat exchangers. Background Technology

[0002] Shell-and-tube heat exchangers are common heat exchange devices in industrial production. They transfer heat through fluid flow between inner and outer tubes and are widely used in chemical, energy, and refrigeration industries. Adaptive flow distribution is a key technology for improving the overall heat exchange efficiency and operational stability of shell-and-tube heat exchangers. Its goal is to dynamically adjust the flow rate of each flow path according to real-time operating conditions, ensuring uniform fluid distribution on the heat exchange surface, avoiding localized overheating or flow dead zones, thereby maximizing heat exchange efficiency and extending equipment life.

[0003] Traditional flow distribution methods often rely on fixed mechanical structures such as guide vanes, orifice plates, or static distributors. Once installed, these structures are difficult to adjust and cannot respond to dynamic changes in fluid parameters or flow differences in different pipelines, which can easily lead to uneven flow in each branch and reduce overall heat exchange efficiency.

[0004] To address this, the present invention proposes an adaptive flow distribution method and device for shell-and-tube heat exchangers. By setting up regular octagonal flow channels with continuously adjustable areas composed of annularly arranged blades at the input ends of multiple sets of flow tubes, and cooperating with staggered flow baffles and speed limiting plates, multi-level fine buffering and control of fluid flow velocity is achieved. Summary of the Invention

[0005] The technical problem to be solved: Traditional mechanical structures cannot respond to dynamic changes in fluid parameters or flow differences in different pipelines.

[0006] To address the shortcomings of existing technologies, this invention provides an adaptive flow distribution method and apparatus for shell-and-tube heat exchangers, thereby solving the technical problems mentioned in the background section.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] The adaptive flow distribution method for shell-and-tube heat exchangers includes the following steps:

[0009] S1. Equipment assembly: Multiple sets of flow tubes are installed in the middle of the housing, and two sets of flow regulating components are installed on one side of the input end of each set of flow tubes.

[0010] S2. For multiple sets of flow tubes arranged in a ring matrix or square matrix inside the shell, a plane coordinate system is established with the center of the matrix as the origin and each flow tube is numbered and marked.

[0011] S3. Flow level determination: By calculating the average flow rate, average velocity and deviation rate of each flow tube from the average value within time T, each flow tube is divided into 5 flow levels. A flow allocation priority matrix is ​​established based on the principle of priority of level and priority of absolute value of deviation rate.

[0012] S4. Calculate the required area of ​​the regular octagonal flow channel based on the flow level. Based on the core relationship formula between flow and channel area, Q=A×v×k, calculate the flow channel area adjustment coefficient α for each flow tube under level 5, and then calculate the target area of ​​the flow channel.

[0013] S5. Adjust the equipment based on the calculated area, and establish the correspondence between the gear disk rotation angle and the channel area by calibrating the gear disk rotation angle. A calibration curve relating to the channel area A is used to adjust the gear disk rotation angle.

[0014] S6. Based on the data collected twice, repeat step S3 to verify whether the adjustment effect meets the set threshold. For flow tubes that do not meet the standard, adjust the adjustment coefficient by fine-tuning the coefficient or lowering the sensitivity coefficient and then recalculating the adjustment coefficient according to the degree of deviation. Perform optimization adjustment and repeat the verification until all threshold requirements are met.

[0015] In one possible implementation, in S1:

[0016] The flow regulating component includes a movable slot on one side of the flow tube input end. Inside the movable slot are eight equilateral trapezoidal blades arranged in an alternating ring. Multiple blades form a regular octagonal flow channel in the middle of the flow tube.

[0017] Each of the multiple blades has a limiting block on one side. Each of the moving grooves has a limiting groove on the side wall adjacent to the limiting block. The multiple limiting blocks are slidably connected inside the adjacent limiting grooves. Both the limiting blocks and the limiting grooves are square in design. Each of the multiple limiting blocks has a sliding rod fixedly connected to the end away from the blade. The input end of the flow tube has a rotating groove on the side near the moving groove. A gear disk is rotatably connected inside the moving groove. The gear disk has 8 sliding grooves arranged in a ring. The 8 sliding rods are located inside the adjacent sliding grooves. The multiple sliding grooves are all designed to be inclined at 45° to the adjacent limiting grooves.

[0018] The housing has a fixed plate installed inside, and a drive wheel is rotatably connected to the fixed plate. The drive wheel meshes with a gear disc. A motor is installed on the fixed plate, and a chain wheel assembly is installed between the output end of the motor and the rotating shaft of the fixed plate.

[0019] The flow tube has two baffles installed inside. A speed limiting plate is also provided on the side of the baffles away from the flow regulating component. The shell has a heat exchange chamber inside, and the heat exchange chamber has interlocking flow limiting plates installed inside.

[0020] In one possible implementation, calculating the target area of ​​the flow channel in S4 includes: based on the core relationship between flow rate and channel area, and according to the flow rate level, the corresponding adjustment coefficient α, and the predetermined baseline channel area. Calculate the total target area and the target area of ​​a single flow regulation component, and ensure that the target area ratio of the two groups of components is 1:1.

[0021] In one possible implementation, the value and calculation method of the adjustment coefficient α in S4 are determined based on the flow level and the absolute value of the deviation rate; a high-sensitivity coefficient is used for levels 5 and 1, a medium-sensitivity coefficient is used for levels 4 and 2, and a fine-tuning coefficient is used for level 3; the finally calculated target area is limited to a minimum area that satisfies... With the maximum area satisfied Within the range.

[0022] In one possible implementation, the equipment adjustment based on the calculated area in S5 includes: determining the target rotation angle of the gear disk that matches the target area based on the correspondence between the gear disk rotation angle and the channel area calibrated in advance through experiments; and starting the motor to drive the gear disk to rotate to the target angle according to the priority matrix order, so as to adjust the area of ​​the flow channel.

[0023] In one possible implementation, the equipment adjustment process in S5 is a step-by-step closed-loop adjustment process: for the same flow pipe, its two sets of flow adjustment components are adjusted in sequence, and the fluid is buffered by a baffle plate in between; after the adjustment of a single set of components and the adjustment of the whole pipe are completed, data is collected by sensors for closed-loop verification, and the new deviation rate is used to determine whether the set level has been reached or whether the adjustment has been recalculated.

[0024] In one possible implementation, the dynamic adjustment in S6 includes: after completing one round of adjustment and waiting for the fluid to stabilize, based on the data collected a second time, verifying whether the preset single-pipe deviation rate threshold and global flow rate and velocity uniformity threshold are met; for flow pipes that do not meet the standards, according to their degree of deviation, by using a fine-tuning coefficient or lowering the sensitivity coefficient and recalculating the adjustment coefficient, performing optimized adjustment, and repeating the verification until all threshold requirements are met.

[0025] Beneficial effects compared to existing technologies:

[0026] In this scheme, the flow rate of the flow tube is determined. The higher the flow rate, the faster the flow rate and the larger the flow rate. Then, the flow channel area of ​​the high-level flow tube is adjusted to slow down and reduce the flow rate. The excess flow rate is distributed to the low-level flow tube. Through comprehensive adjustment, the difference in flow rate and flow rate of each flow tube is ensured to be less than the set threshold, thereby achieving the effect of reasonable flow distribution and improving heat conversion efficiency. Attached Figure Description

[0027] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0028] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 This is a schematic diagram of the heat exchange cavity of the present invention;

[0030] Figure 3 This is a schematic diagram of the gear disk of the present invention;

[0031] Figure 4 This is a schematic diagram of the movable slot of the present invention;

[0032] Figure 5 This is a schematic diagram of the blade of the present invention;

[0033] Figure 6 This is a schematic diagram of the groove of the present invention;

[0034] Figure 7 This is a schematic diagram of the flow tube arrangement of the present invention;

[0035] Figure 8 This is a schematic diagram of the regular octagonal flow channel of the present invention;

[0036] Figure 9 This is a schematic diagram illustrating the area variation of the regular octagonal flow channel of the present invention;

[0037] Figure 10 This is a flowchart of the method steps of the present invention.

[0038] Legend: 1. Shell; 2. Flow pipe; 3. Moving groove; 4. Blade; 5. Limiting block; 6. Limiting groove; 7. Slide rod; 8. Rotating groove; 9. Gear disk; 10. Slide groove; 11. Fixed plate; 12. Drive wheel; 13. Motor; 14. Chain wheel assembly; 15. Baffle plate; 16. Speed ​​limiting plate; 17. Heat exchange chamber; 18. Flow limiting plate. Detailed Implementation

[0039] Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention can also be implemented in various different forms, and therefore the present invention is not limited to the embodiments described below. In addition, for the purpose of more clearly describing the present invention, parts not connected to the invention will be omitted from the drawings.

[0040] The technical solution in this application embodiment is to solve the problems mentioned in the background art, and the overall idea is as follows:

[0041] Example:

[0042] Please refer to Figures 1 to 6 As shown in the figure, this embodiment introduces the specific structure of the adaptive flow distribution device for the shell-and-tube heat exchanger, including a shell 1, with multiple sets of flow tubes 2 installed in the middle of the shell 1. The multiple sets of flow tubes 2 are arranged in a matrix, and two sets of flow regulating components are installed on one side of the input end of each set of flow tubes 2.

[0043] The flow regulating component includes a movable groove 3 located on one side of the inlet end of the flow tube 2. Eight blades 4 are installed inside the movable groove 3. The blades 4 are all equilateral trapezoidal in design and arranged in a ring with an alternating angle of 45°, thus forming a regular octagonal flow channel in the center. Each side of the blades 4 is provided with a limiting block 5. A limiting groove 6 is provided on the side wall of the movable groove 3 adjacent to the limiting block 5. The limiting blocks 5 are slidably connected to the interior of the adjacent limiting grooves 6. Both the limiting blocks 5 and the limiting grooves 6 are square in design. The limiting grooves 6 restrict the movement direction of the limiting blocks 5, thereby restricting the movement direction of the blades 4, so that the multiple ring-arranged blades 4 contract or expand along the center of the ring, thereby enlarging or shrinking the area of ​​the central regular octagonal flow channel.

[0044] Multiple limiting blocks 5 are fixedly connected to slide rods 7 at the ends away from blades 4. A rotating groove 8 is opened on the side of the input end of the flow tube 2 near the moving groove 3. Multiple slide rods 7 extend into the interior of the moving groove 3. A gear disk 9 is rotatably connected inside the moving groove 3. Eight sliding grooves 10 are arranged in a ring on the gear disk 9. The eight slide rods 7 are located inside the adjacent sliding grooves 10. Multiple sliding grooves 10 are inclined at 45° to the adjacent limiting grooves 6. When the gear disk 9 drives the sliding grooves 10 to rotate, the end of the sliding groove 10 away from the limiting groove 6 gradually approaches the limiting groove 6. The limiting groove 6 sidewall and the sliding groove 10 sidewall restrict the slide rods 7 to move towards the center of the regular octagonal flow channel, thereby driving multiple blades 4 to move towards the center to reduce the area of ​​the regular octagonal flow channel.

[0045] When the gear disk 9 drives the slide groove 10 to rotate, causing one end of the slide groove 10 away from the limiting groove 6 to gradually approach the limiting groove 6, the other end of the slide groove 10 will inevitably move away from the limiting groove 6. At this time, the gear disk 9 is rotated in the opposite direction, which drives the other end away from the limiting groove 6 to approach the limiting groove 6, thereby driving the slide rod 7 away from the center position of the regular octagonal flow channel, and then driving multiple blades 4 to expand outward to increase the area of ​​the regular octagonal flow channel.

[0046] A fixed plate 11 is installed inside the housing 1. A drive wheel 12 is rotatably connected to the fixed plate 11. The drive wheel 12 meshes with the gear disk 9. A motor 13 is installed on the fixed plate 11. A chain wheel assembly 14 is installed between the output end of the motor 13 and the rotation shaft of the fixed plate 11. By starting the motor 13, the chain wheel assembly 14 drives the fixed plate 11, which in turn drives the gear disk 9 to rotate, thereby achieving the function of adjusting the size of the octagonal flow channel area.

[0047] Two sets of flow regulating components are arranged one after the other on one side of the input end of the flow tube 2, forming two regular octagonal flow channels. Two baffles 15 are installed inside the flow tube 2. The two baffles 15 and the two sets of flow regulating components are alternately installed on one side of the input end of the flow tube 2, forming an alternating design of flow regulating components, baffles 15, flow regulating components, and baffles 15. The center of the baffle 15 is on the same straight line as the center of the flow channel. When the flow regulating components regulate the flow, as the area of ​​the flow channel gradually decreases, the flow velocity of the fluid in the middle of the flow channel continuously increases. The baffle 15 located between the two sets of flow regulating components prevents the fluid from passing too fast between the two sets of flow regulating components, which would affect the secondary flow regulation. The baffle 15 can slow down the fluid and fill the space in the middle of the two sets of flow regulating components.

[0048] The output end of flow tube 2 is equipped with flow and velocity sensors to monitor the changes in flow and velocity of flow tube 2 in real time.

[0049] The flow baffle 15 on one side of the output end of the flow tube 2 prevents the fluid from flowing too fast inside the flow tube 2, which would affect the heat exchange efficiency. At the same time, a speed limiter 16 is also provided on the side of the flow baffle 15 away from the flow regulating component. The speed limiter 16 is installed inside the flow tube 2. The speed limiter 16 can further slow down the fluid flow rate inside the flow tube 2 to improve the heat exchange efficiency.

[0050] The shell 1 has a heat exchange chamber 17 inside, and a flow limiting plate 18 is installed inside the heat exchange chamber 17. The flow limiting plates 18 are installed alternately inside the heat exchange chamber 17 to form a wave-shaped fluid channel, thereby slowing down the flow rate of the fluid inside the heat exchange chamber 17 to improve the heat exchange efficiency.

[0051] like Figures 7 to 10 As shown, based on the above-mentioned adaptive flow distribution device for shell-and-tube heat exchangers, this embodiment also introduces an adaptive flow distribution method for shell-and-tube heat exchangers, which includes the following steps:

[0052] S1. Equipment assembly, specifically including:

[0053] Multiple sets of flow tubes 2 are installed in the middle of the housing 1. Two sets of flow regulating components are installed on the input end side of each set of flow tubes 2. The flow regulating components include multiple equilateral trapezoidal blades 4 arranged in a ring in the middle. The two sets of movable blades 4 form two adjustable octagonal flow channels in the middle of the flow tubes 2.

[0054] Two flow baffles 15 are installed inside the flow tube 2, and their positions are staggered with those of the two sets of flow regulating components. A speed limiter 16 is also installed inside the flow tube 2 on the side of the flow baffles 15 away from the flow regulating components.

[0055] Inside the heat exchange chamber 17 of the shell 1, staggered flow limiting plates 18 are installed.

[0056] S2. Mark multiple sets of flow tubes 2 with a matrix. The flow tubes 2 inside the housing 1 can be arranged in a ring matrix or a square matrix according to actual needs. All of them establish a plane coordinate system with the center of the matrix as the origin.

[0057] by Figure 7 Taking a 5×5 square matrix arrangement as an example, the number of flow tubes 2 is 25, and they are numbered R1, R2, ..., R2 according to the diagram from top to bottom and left to right. 25 The flow tube 2 at the center is marked as R. 13 (0,0), the four corners are R1(-2,2), R5(2,2), R 21 (-2, -2), R 25 (2, -2).

[0058] S3, Traffic Level Determination

[0059] S3.1. Simultaneously install a high-precision flow sensor (measuring flow rate H) and a flow velocity sensor (measuring flow velocity S) at the output end of each group of flow tubes 2. Under the same operating conditions and within the same time period T, simultaneously collect the real-time flow rate H of all flow tubes 2. i and flow rate S i (i=1~25), after data collection, the following calculations and analyses are performed:

[0060] Calculate the average flow rate and average flow velocity:

[0061] Average flow rate: ,in Total number of flow tubes 2 ;

[0062] Average flow velocity: ;

[0063] Assuming the total flow rate of the 25 flow tubes 2 is ,but The total flow velocity is ,but .

[0064] Calculate the deviation rate of each tube from the average value:

[0065] Calculate the flow deviation rate and flow velocity deviation rate for each flow tube 2 separately to reflect the degree of deviation of the single tube data from the average value:

[0066] Flow deviation rate: ;

[0067] Flow rate deviation rate: ;

[0068] Explanation of deviation rate: , When the value is positive, the flow rate / velocity of a single pipe is higher than the average value; when the value is negative, it is lower than the average value, and the larger the absolute value, the more serious the deviation.

[0069] S3.2 and Level 5 flow rate classification require simultaneous satisfaction of both flow rate and flow velocity deviation rate conditions to ensure synergy between the two indicators and avoid misjudgment based on a single indicator. Specifically:

[0070] Level 5 is the highest level, indicating excessive or excessive speed, with a corresponding flow deviation rate. ≥20%, flow rate deviation rate ≥20%, the adjustment direction is to significantly reduce the channel area;

[0071] Level 4 indicates a minor overspeed, with a corresponding flow deviation rate of 10% or less. <20%, flow velocity deviation rate 10% ≤ If the percentage is less than 20%, the adjustment direction is to slightly reduce the channel area;

[0072] Level 3 is the baseline level, which is within the normal range, corresponding to a flow deviation rate of -10%. <10%, Flow velocity deviation rate -10%< If the area is less than 10%, the adjustment direction is to maintain or fine-tune the channel area.

[0073] Level 2 indicates a slight underspeed, corresponding to a flow deviation rate of -20%. ≤-10%, flow velocity deviation rate -20%< ≤-10%, the adjustment direction is to slightly increase the channel area;

[0074] Level 1 is the lowest level, indicating severe underspeed, with a corresponding flow deviation rate. ≤-20%, Flow rate deviation rate ≤-20%, the adjustment direction is to significantly expand the channel area;

[0075] For example, a flow tube 2 =25% but If the percentage is 15%, it will not be classified as Level 5, and the sensor or operating condition needs to be re-examined.

[0076] S3.3 Establish a flow allocation priority matrix, which prioritizes based on level and absolute value of deviation rate. The level priority is: 5 > 4 > 3 > 2 > 1, with higher levels showing more severe deviations and receiving priority adjustment. Within the same level, the larger the absolute value of the deviation rate, the higher the priority. The priority matrix format (using a 5×5 matrix as an example) is as follows:

[0077]

[0078] By establishing a priority matrix, the adjustment order is guided, avoiding system fluctuations caused by adjusting multiple flow tubes simultaneously. High-priority tubes are adjusted first, followed by low-priority tubes.

[0079] S4. Calculate the required area size of the regular octagonal flow channel based on the flow rate level;

[0080] S4.1, Reference channel area A0: The initial channel area of ​​a single flow regulating component in the flow tube 2 design; the initial total area of ​​the two components is A. 总0 =A0+A0=2A0, which corresponds to the baseline state of level 3;

[0081] Flow coefficient k: A constant determined by fluid density, viscosity characteristics and the shape of a regular octagonal channel, calibrated through previous experiments; for example, when water is the medium, k = 0.92.

[0082] The core relationship between flow rate and channel area is: Q = A × v × k (Q is the flow rate, A is the area of ​​a single channel, and v is the flow velocity), with the goal being the adjusted flow rate. , ;

[0083] Adjustment coefficient α: A proportional coefficient used to correct the channel area. When α>1, the area is expanded; when α<1, the area is reduced.

[0084] Area upper and lower limits: minimum area To avoid complete closure of the channel leading to fluid blockage; maximum area To avoid exceeding the adjustment range of the blade 4 structure;

[0085] S4.2 Calculation of the adjustment coefficient α: It is calibrated according to the level. First, α is determined according to the flow level, and then the adjustment range is optimized by combining the absolute value of the deviation rate to avoid over-adjustment or under-adjustment. Specifically:

[0086] The formula for the adjustment coefficient corresponding to level 5 is: Where 0.8 is a high sensitivity coefficient, used to significantly reduce the channel area. Example: If , ,but ;

[0087] The formula for the adjustment coefficient corresponding to level 4 is: Where 0.6 is the medium sensitivity coefficient, used to slightly reduce the channel area. Example: If , ,but ;

[0088] The adjustment coefficient for level 3 is α = 1 ± 0.05, which is a fine-tuning coefficient. It is adjusted according to the direction of the deviation; a positive deviation is taken as 0.95, and a negative deviation as 1.05. Example: If... , ,but ;

[0089] The formula for the adjustment coefficient corresponding to level 2 is: Where 0.6 is the medium sensitivity coefficient, used to slightly increase the channel area. Example: If , ,but ;

[0090] The formula for the adjustment coefficient corresponding to Level 1 is: Where 0.8 is a high sensitivity coefficient, used to significantly increase the channel area. Example: If , ,but .

[0091] S4.3, The two sets of flow regulation components work together to calculate the target area:

[0092] Since there are two sets of flow regulating components at the input end of flow tube 2, the area ratio of the two sets of components needs to be maintained at 1:1. Therefore, the target area of ​​a single set of components is... Total target area ,in This represents the initial total area;

[0093] Finally, the calculated results need to be verified. , Does it meet the requirements? If the value exceeds the limit, the upper or lower limit will be used, for example, after level 5 adjustment. Then force take .

[0094] S5. Adjust the equipment according to the calculated area.

[0095] S5.1 Preparations before adjustment

[0096] The relationship between the rotation angle of gear disk 9 and the channel area was established through prior experimental measurement. (Gear disk 9 rotation angle, unit: °) - A (Channel area, unit: m²)2 Calibration curves, for example:

[0097] Gear disk 2 rotates 30° clockwise, and the area of ​​a single channel increases from... Shrink to ;

[0098] Rotate counterclockwise by 20°, the area of ​​a single channel increases from Expand to The calibration curve is stored in the control system for quick querying of the target angle.

[0099] S5.2 Step-by-step adjustment process (in order of priority matrix)

[0100] Using a certain 5-stage flow meter R8, the target ,initial For example:

[0101] Target angle query: Based on the calibration curve, The corresponding gear disk 9 rotates clockwise by an angle °;

[0102] Motor 13 control: The control system sends a command to the motor 13 to start the motor 13 to drive the chain wheel assembly 14, which in turn drives the drive wheel 12 to rotate, causing the gear disk 9 to rotate 32° clockwise;

[0103] During rotation, the slide groove 10 of the gear disk 9 pushes the slide rod 7 to move towards the center of the regular octagon, and the blade 4 moves along the limiting groove 6. Multiple blades 4 simultaneously contract towards the center position, thereby gradually reducing the area of ​​the flow channel.

[0104] First group component adjustment: First adjust the first group of flow regulation components to the target area. The sensor provides real-time feedback on the flow rate. Flow rate ;

[0105] Baffle 15 buffer: After the fluid passes through the first set of components, it is slowed down by the intermediate baffle 15, filling the gap between the two sets of components and preventing the flow rate from being too fast and affecting the second set of regulation.

[0106] Second group component adjustment: Adjust the second group of components at the same target angle to ensure that the areas of the two groups are consistent, at which point the total channel area is;

[0107] Closed-loop verification: After adjustment, continuously collect data from R8. , Calculate the new deviation rate:

[0108] like , Once the flow rate enters the 3rd level range (±10%), the adjustment is complete, and the process moves to the next priority flow tube 2.

[0109] If it remains at level 4 / 5, recalculate the adjustment factor α (e.g., , Recalculate according to the Level 4 formula Target area 0.00458 Repeat steps 1-5 until the target is met;

[0110] Adjustment of lower-level tubes: After adjusting the higher-level tubes (levels 5 and 4), adjust the tubes (levels 2 and 1) according to priority, following the same adjustment logic.

[0111] 3-stage tube fine-tuning: After all non-3-stage tubes have been adjusted, check the deviation rate of the 3-stage tubes. If it exceeds ±5%, proceed as follows: or Fine-tuning to ensure overall stability.

[0112] S6, Dynamic Change Adjustment

[0113] After completing one round of S3-S5 adjustment process, the active adjustment action is paused, and the fluid stabilization waiting phase begins. The waiting time is set to 2-3 minutes, with the specific duration dynamically adjusted according to the fluid viscosity. After the stabilization period, secondary data acquisition is initiated, with the acquisition specifications being completely consistent with S3. Based on the secondary acquisition data, key indicators are recalculated to verify whether the adjustment effect meets the set thresholds. Two core thresholds are verified simultaneously.

[0114] Single tube threshold: all flow tubes 2 ≤10% and ≤10%, with no single tube exceeding the level 3 range;

[0115] Global uniformity threshold: the difference in flow rate between any two flow tubes 2 Flow velocity difference , where i and j (i≠j) are arbitrary flow tube numbers;

[0116] Based on the verification results, the following cases will be categorized, and corresponding optimization strategies will be implemented accordingly:

[0117] Fully compliant: This indicates that the adjustment effect has met expectations, the flow distribution uniformity meets the design standards, and the heat exchange efficiency is in the optimal range. At this time, no additional adjustment is required, and the system automatically switches to the normal dynamic cycle: When the operating conditions are stable (inlet temperature and pressure fluctuations ≤ ±2%), the entire S3-S6 process is repeated every 5 minutes; when the operating condition fluctuations are > ±2%, it automatically switches to repeating once every 1 minute to continuously track changes in operating conditions.

[0118] Partial compliance or non-compliance: This means some flow tubes 2 do not meet the threshold. First, non-compliant flow tubes 2 are screened, prioritized by the degree of deviation, and processed first, with the flow tube 2 having the largest absolute deviation rate. α is adjusted according to the direction and degree of deviation.

[0119] If the deviation is close to the threshold, use the fine-tuning coefficient. Avoid over-adjustment;

[0120] If the deviation exceeds the threshold by a significant amount, re-execute S4. The calculation logic is adjusted, but the sensitivity coefficient is reduced by 20% (0.64 for level 5 / 1, and 0.48 for level 4 / 2) to decrease the adjustment range and reduce system fluctuations.

[0121] According to the optimized For pipes that do not meet the standards, implement the step-by-step adjustment process of S5. After the adjustment is completed, wait for a 2-minute stabilization period and repeat the verification of the two core thresholds until all flow pipes meet the threshold requirements.

[0122] Finally, it should be noted that the above embodiments are merely examples for clearly illustrating the present invention and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An adaptive flow distribution method for a shell-and-tube heat exchanger, characterized in that, Includes the following steps: S1. Equipment assembly: Multiple sets of flow tubes (2) are installed in the middle of the housing (1), and two sets of flow regulating components are installed on the input side of each set of flow tubes (2). S2. Multiple flow tubes (2) are arranged in a ring matrix or square matrix inside the shell (1). A plane coordinate system is established with the center of the matrix as the origin and each flow tube (2) is numbered and marked. S3. Flow level determination: By calculating the average flow rate, average velocity and deviation rate of each flow tube (2) from the average value within time T, each flow tube (2) is divided into 5 flow levels. A flow allocation priority matrix is ​​established based on the principle of priority of level and priority of absolute value of deviation rate. S4. Calculate the area size required for the regular octagonal flow channel based on the flow level. Based on the core relationship formula Q=A×v×k between flow and channel area, calculate the flow channel area adjustment coefficient α for each flow tube (2) under level 5, and then calculate the target area of ​​the flow channel. S5. Adjust the equipment according to the calculated area, and establish the correspondence between the rotation angle of the gear disk (9) and the channel area by calibrating the rotation angle of the gear disk (9). The calibration curve relating to the channel area A is used to adjust the rotation angle of the gear disk (9) according to the calibration curve. S6. Based on the data collected twice, repeat step S3 to verify whether the adjustment effect meets the set threshold. For flow tubes that do not meet the standard, adjust the adjustment coefficient by fine-tuning the coefficient or lowering the sensitivity coefficient and then recalculating the adjustment coefficient according to the degree of deviation. Perform optimization adjustment and repeat the verification until all threshold requirements are met.

2. The adaptive flow distribution method for a shell-and-tube heat exchanger as described in claim 1, characterized in that, In S1: The flow regulating component includes a movable groove (3) opened on one side of the inlet end of the flow tube (2). Inside the movable groove (3) are eight equilateral trapezoidal blades (4) arranged in an alternating ring. Multiple blades (4) form a regular octagonal flow channel in the middle of the flow tube (2). Each of the multiple blades (4) is provided with a limiting block (5) on one side. Each of the moving grooves (3) is provided with a limiting groove (6) at a position adjacent to the limiting block (5). The multiple limiting blocks (5) are slidably connected to the inside of the adjacent limiting grooves (6). Both the limiting blocks (5) and the limiting grooves (6) are square. Each of the multiple limiting blocks (5) is fixedly connected with a sliding rod (7) at the end away from the blade (4). A rotating groove (8) is provided on the side of the flow tube (2) near the moving groove (3). A gear disk (9) is rotatably connected inside the moving groove (3). Eight sliding grooves (10) are arranged in a ring on the gear disk (9). The eight sliding rods (7) are located inside the adjacent sliding grooves (10). The multiple sliding grooves (10) and the adjacent limiting grooves (6) are all designed to be inclined at 45°. Inside the housing (1), a fixed plate (11) is installed. A drive wheel (12) is rotatably connected to the fixed plate (11). The drive wheel (12) meshes with the gear disk (9). A motor (13) is installed on the fixed plate (11). A chain wheel assembly (14) is installed between the output end of the motor (13) and the rotating shaft of the fixed plate (11). Two flow baffles (15) are installed inside the flow tube (2). A speed limiting plate (16) is also provided on the side of the flow baffle (15) away from the flow regulating component. A heat exchange chamber (17) is provided inside the shell (1). Interlocking flow limiting plates (18) are installed inside the heat exchange chamber (17).

3. The adaptive flow distribution method for a shell-and-tube heat exchanger as described in claim 1, characterized in that, The S4 calculation of the target area of ​​the flow channel includes: based on the core relationship between flow rate and channel area, and according to the flow rate level, the corresponding adjustment coefficient α, and the predetermined baseline channel area. Calculate the total target area and the target area of ​​a single flow regulation component, and ensure that the target area ratio of the two groups of components is 1:

1.

4. The adaptive flow distribution method for a shell-and-tube heat exchanger as described in claim 1, characterized in that, The value and calculation method of the adjustment coefficient α in S4 are determined based on the flow level and the absolute value of the deviation rate; a high sensitivity coefficient is used for level 5 and level 1, a medium sensitivity coefficient is used for level 4 and level 2, and a fine-tuning coefficient is used for level 3; the final calculated target area is limited to a minimum area that satisfies With the maximum area satisfied Within the range.

5. The adaptive flow distribution method for a shell-and-tube heat exchanger as described in claim 1, characterized in that, The equipment adjustment based on the calculated area in S5 includes: determining the target rotation angle of the gear disk (9) that matches the target area based on the correspondence between the rotation angle of the gear disk (9) and the channel area as determined by the experiment; and starting the motor (13) to drive the gear disk (9) to rotate to the target angle in the order of the priority matrix to adjust the area of ​​the flow channel.

6. The adaptive flow distribution method for a shell-and-tube heat exchanger as described in claim 1, characterized in that, The equipment adjustment process in S5 is a step-by-step closed-loop adjustment process: For the same flow pipe (2), its two sets of flow adjustment components are adjusted in sequence, and the fluid is buffered by the baffle plate (15) in between; after the adjustment of a single component and the adjustment of the whole pipe are completed, data is collected by the sensor for closed-loop verification, and the new deviation rate is used to determine whether the set level has been reached or the adjustment is recalculated.

7. The adaptive flow distribution method for a shell-and-tube heat exchanger as described in claim 1, characterized in that, The dynamic adjustment in S6 includes: after completing one round of adjustment and waiting for the fluid to stabilize, based on the data collected a second time, verifying whether the preset single tube deviation rate threshold and global flow rate and velocity uniformity threshold are met; for flow tubes (2) that do not meet the standards, according to their degree of deviation, the adjustment coefficient is recalculated by fine-tuning the coefficient or lowering the sensitivity coefficient, and the optimization adjustment is performed, and the verification is repeated until all threshold requirements are met.

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