Gate valve micro-channel leakage prevention and control device and prevention and control method based on grid Boltzmann

Abstract

The invention discloses a gate valve micro-channel leakage prevention and control device and a prevention and control method based on lattice Boltzmann. The gate valve micro-channel leakage prevention and control device comprises a plurality of sealing blocks and heat insulation blocks which are evenly distributed in a staggered mode in the circumferential direction of one inner side wall face of a micro-channel. Each sealing block comprises a piezoelectric ceramic block, an SMA, a temperature sensor and a heating assembly; the bottom surface of the piezoelectric ceramic block is arranged on the inner side wall surface of the micro-channel; the SMA is arranged on the top surface of the piezoelectric ceramic block; the temperature sensor is used for monitoring the temperature of the SMA in real time; the heating assembly can heat the SMA. The SMA and piezoelectric ceramic combined structure is adopted, a wear area is identified through piezoelectric signals, the SMA is heated through a PID temperature control strategy to trigger the shape memory effect, compensation displacement is generated to recover the sealing state in real time, wear monitoring and closed-loop compensation are achieved, and therefore self-repairing after leakage is caused by surface wear of the microgap of the gate valve sealing ring can be achieved, and the service life of the gate valve sealing ring is prolonged. The anti-leakage gate valve sealing structure has the advantages of being good in anti-leakage effect, high in control precision, high in response speed and the like.

Description

Technical Field

[0001] This invention relates to the field of microfluidics and control, and in particular to a gate valve microchannel leakage prevention and control device and a lattice Boltzmann-based prevention and control method. Background Technology

[0002] The surface of gate valve microchannels inevitably contains rough elements formed by machining defects, biofouling, or corrosion. Conclusions show that these rough elements on the microchannel wall significantly alter the local flow field structure, leading to abnormally increased pressure drop, flow fluctuations, and even induced turbulence, severely impacting valve control accuracy and system energy efficiency. For example, in patent CN115464221A, response surface methodology is used to optimize EDM parameters combined with flow field simulation, enabling precise control of the micro-orifice shape and optimizing the throttling effect. This solves the problem of insufficient control accuracy in traditional labyrinth-type throttling valves due to inconsistencies in machining parameters and orifice shape.

[0003] For example, in the patent disclosed in CN120406173A, by integrating temperature-compensated adaptive filtering and variable step-size gradient descent sealing position optimization algorithm, the gate valve can accurately control the sealing surface position in real time under wide temperature range conditions, solving the problems of sealing surface deformation, increased leakage rate and control response lag caused by uneven thermal expansion.

[0004] For example, in the patent disclosed in CN222836384U, a mechanical linkage detection mechanism is used to trigger an alarm circuit for leaking liquid, which solves the problem that traditional gate valves cannot monitor leaks in real time, resulting in resource waste and safety risks.

[0005] For example, in the patent disclosed in CN223242120U, by adding a limiting boss that extends beyond the outer edge between the sealing parts, the gate is kept stable when installed vertically, which solves the problems of leakage, shaking and damage to the sealing surface caused by the tilting of the gate valve.

[0006] The technical solutions proposed in the above-mentioned prior art each have their advantages, but they lack accurate calculation of flow loss after the rough elements in the sealing micro-gap of the gate valve undergo slight wear due to repeated opening and closing of the gate, as well as high-precision anti-leakage control measures based on the real-time calculation data. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to address the shortcomings of the prior art by providing a gate valve microchannel leakage prevention and control device and a lattice Boltzmann-based prevention and control method. The gate valve microchannel leakage prevention and control device and the lattice Boltzmann-based prevention and control method establish a microchannel model through the lattice Boltzmann analysis method and calculate the quantitative relationship between the inlet and outlet flow difference and the rough element height, providing a basis for real-time wear monitoring and closed-loop compensation control based on shape memory alloy (SMA) and piezoelectric ceramics.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0009] A gate valve microchannel leakage prevention and control device is installed on the inner wall of the gate valve microchannel, including a plurality of sealing blocks and heat insulation blocks evenly and alternately arranged along the circumference of one inner wall of the microchannel.

[0010] Each sealing block includes a piezoelectric ceramic block, SMA, a temperature sensor, and a heating assembly.

[0011] The bottom surface of the piezoelectric ceramic block is arranged on the inner wall of the microchannel.

[0012] SMA is positioned on the top surface of the piezoelectric ceramic block.

[0013] Temperature sensors are used to monitor the temperature of the SMA in real time, and heating components can heat the SMA.

[0014] It also includes a PID controller, which is connected to the piezoelectric ceramic block, temperature sensor and heating assembly respectively.

[0015] The piezoelectric ceramic block is fan-shaped with a central angle of 0~30°.

[0016] The heating element is an electric heating coil, which is placed between the piezoelectric ceramic block and the SMA.

[0017] The control method based on lattice Boltzmann includes the following steps.

[0018] Step 1, Potential Leakage Area Detection: The piezoelectric ceramic block in each sealing block provides real-time feedback on the pressure F it bears, and compares the pressure F with the set piezoelectric ceramic compressive stress threshold. Compare; when F < If the leak occurs, the sealing surface area corresponding to the sealing block is considered a potential leakage area; otherwise, there is no leakage.

[0019] Step 2: Calculate the radial displacement x of the SMA: For the potential leakage area, the required radial displacement x of the SMA is calculated based on the pressure F and the lattice Boltzmann analysis method.

[0020] Step 3: Calculate the target heating temperature T required for the SMA based on the radial displacement x of the SMA.

[0021] Step 4: The heating component is activated to heat the SMA to the target heating temperature T calculated in Step 3.

[0022] Step 5: The temperature sensor monitors the temperature of the SMA in real time and keeps the SMA at the target heating temperature T.

[0023] In step 1, the piezoelectric ceramic is subjected to a pressure threshold. If the value is the mechanical preload of the gate valve sealing surface when there is no oil pressure, then the pressure F is calculated using the following formula:

[0024]

[0025] In the formula, K is the stiffness of the piezoelectric ceramic block; The piezoelectric constant of the piezoelectric ceramic block; This is the output voltage of the piezoelectric ceramic block.

[0026] In step 2, the Fx curve is obtained based on the lattice Boltzmann analysis method, and its specific expression is as follows:

[0027]

[0028] In the formula, represents the simulation fitting coefficients, where i is the term number of the polynomial, with a value ranging from 0 to 7.

[0029] Step 2, the method for obtaining the Fx curve based on the lattice Boltzmann algorithm, includes the following steps:

[0030] Step 2-1: Based on the lattice Boltzmann method and the gate valve microchannel to be controlled, construct a micro-gap analysis and calculation model containing rough element features, set boundary conditions and perform flow iteration until the flow field converges and the flow rate stabilizes.

[0031] Step 2-2: Set all rough elements in the micro-gap analysis calculation model to the same height x, use the momentum exchange method to calculate the instantaneous force at each boundary grid point, calculate the change of the fluid force on the rough element boundary before and after the collision, and obtain the fluid extrusion force F borne by the rough element.

[0032] Step 2-3: Replace the roughness element height x in step 2-2, repeat step 2-2, and obtain the Fx curve.

[0033] It also includes step 6, calculating the valve seat flow loss rate. The specific calculation formula is as follows:

[0034]

[0035] In the formula, This refers to the inlet flow rate of the gate valve microchannel; x is the SMA radial displacement calculated in step 2; j is... The term number of the polynomial in the polynomial ranges from 0 to 4; for The polynomial coefficients of the j-th term are obtained through simulation fitting.

[0036] It also includes step 7, correcting the target heating temperature T: the piezoelectric ceramic block in the potential leak area detection continues to provide real-time feedback on the pressure F it is subjected to, and... Compare; if F < If the target heating temperature T is not reached, repeat steps 2 to 6 to adjust the target heating temperature T until F is reached. .

[0037] In step 3, the target heating temperature T is calculated using the following formula:

[0038]

[0039] In the formula, This corresponds to the SMA length in the sealing block; This is the initial strain of the SMA; It is SMA stress; It is the phase transition modulus of SMA; Initial ambient temperature; It is the current martensite volume fraction Young's modulus of the lower SMA; This is the maximum recoverable strain of the SMA; It is the martensite volume fraction of SMA.

[0040] The present invention has the following beneficial effects:

[0041] 1. This invention adopts a combination structure of shape memory alloy (SMA) and piezoelectric ceramic. The wear area is identified by piezoelectric signal, and the SMA is heated by PID temperature control strategy to induce shape memory effect, generating compensating displacement to restore the sealing state in real time. This realizes wear monitoring and closed-loop compensation, thereby solving the leakage problem in the microchannel between the valve plate and valve seat of the gate valve.

[0042] 2. This invention constructs a lattice Boltzmann model containing different roughness element height characteristics, establishes the correlation between the roughness element height in the micro-gap and the difference in inlet and outlet flow rates through analysis and calculation, and determines the optimal roughness element height.

[0043] 3. This invention can be used to solve the self-repair problem caused by surface wear of the micro-gap of the gate valve sealing ring, extend the service life of the gate valve sealing structure, and has the advantages of good leak prevention effect, high control accuracy and fast response speed.

[0044] 4. The heat insulation block in this invention can ensure precise temperature control of the SMA in each sealing block. Attached Figure Description

[0045] Figure 1 The diagram shows a schematic of the structure of a gate valve microchannel leakage prevention device according to the present invention in a gate valve.

[0046] Figure 2 The diagram shows a plan view of a gate valve microchannel leakage prevention and control device according to the present invention.

[0047] Figure 3 An enlarged schematic diagram of the sealing block in this invention is shown.

[0048] Figure 4 An enlarged structural schematic diagram of each SMA in this invention is shown.

[0049] Figure 5 A flowchart of the control method based on lattice Boltzmann in this invention is shown.

[0050] Figure 6 The diagram shows the geometric structure of the triangular rough element in the control method based on lattice Boltzmann of this invention.

[0051] Figure 7 The diagram shows the final flow field velocity distribution in the control method based on lattice Boltzmann of this invention.

[0052] Figure 8 The final flow convergence history is shown in the control method based on lattice Boltzmann of this invention.

[0053] Figure 9 The percentage difference between inlet and outlet flow rates is shown in the control method based on lattice Boltzmann of this invention.

[0054] Figure 10 The simulation response diagram of PID closed-loop temperature control in the control method based on lattice Boltzmann of this invention is shown.

[0055] Among them are:

[0056] 10. Gate valve; 11. Valve plate; 12. Valve seat; 13. Dynamic sealing ring; 14. Static sealing ring; 141. Groove; 15. Microchannel; 20. Leakage control device; 30. Sealing block; 31. Piezoelectric ceramic block; 32. SMA; 33. Temperature sensor; 34. Heating assembly; 40. Insulation block. Detailed Implementation

[0057] The present invention will now be described in further detail with reference to the accompanying drawings and specific preferred embodiments.

[0058] In the description of this invention, it should be understood that the terms "left side," "right side," "upper part," "lower part," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. "First," "second," etc., do not indicate the importance of the components, and therefore should not be construed as a limitation of this invention. The specific dimensions used in this embodiment are only for illustrating the technical solution and do not limit the scope of protection of this invention.

[0059] like Figure 1 As shown, the gate valve 10 includes a valve plate 11 and a valve seat 12. The valve plate 11 can slide up and down, and is provided with two dynamic sealing rings 13. The valve seat is provided with two static sealing rings 14. When the valve plate descends and sits in the valve seat, the two dynamic sealing rings and the two static sealing rings seal and cooperate, forming two microchannels 15.

[0060] A leakage prevention device 20 of the present invention is provided on any inner wall surface of each microchannel, that is, the side wall surface of the dynamic sealing ring facing the microchannel or the side wall surface of the static sealing ring facing the microchannel. In this embodiment, it is preferable to provide one such device on each side wall surface of the static sealing ring facing the microchannel. Figure 2 The groove 141 shown contains a leak prevention device 20 of the invention.

[0061] like Figure 2 and Figure 3 As shown, a gate valve microchannel leakage prevention and control device, namely leakage prevention and control device 20, includes a PID controller, m sealing blocks 20 and m heat insulation blocks 30 evenly and alternately arranged along the inner wall of one microchannel. Each sealing block is preferably fan-shaped, and its central angle is preferably 0~30°. In this embodiment, it is preferably 15°. Therefore, the number of sealing blocks m is preferably 24. Adjacent sealing blocks are isolated by heat insulation blocks to ensure precise temperature control of the SMA in each sealing block.

[0062] like Figure 3 As shown, each sealing block includes a piezoelectric ceramic block 21, an SMA (short for shape memory alloy block) 22, a temperature sensor 23, and a heating element 24. The bottom surface of the piezoelectric ceramic block is preferably embedded in the groove 141, preferably in a fan shape, with the central angle being the same as that of the sealing block. The SMA is disposed on the top surface of the piezoelectric ceramic block, such as through bonding, and its shape is as follows: Figure 4 As shown.

[0063] A temperature sensor is used to monitor the temperature of the SMA in real time; in this embodiment, a thermocouple or similar device embedded in the SMA is preferred. A heating element heats the SMA; preferably, a heating coil is positioned between the piezoelectric ceramic block and the SMA.

[0064] The PID controller is connected to the piezoelectric ceramic block, the temperature sensor, and the heating assembly, respectively.

[0065] like Figure 5 As shown, a control method based on lattice Boltzmann includes the following steps.

[0066] Step 1, Potential Leakage Area Detection: The piezoelectric ceramic block in each sealing block provides real-time feedback on the pressure F it bears, and compares the pressure F with the set piezoelectric ceramic compressive stress threshold. Compare them. When F < If the leak occurs, the sealing surface area corresponding to the sealing block is considered a potential leakage area; otherwise, there is no leakage.

[0067] piezoelectric ceramics compressive stress threshold If the value is the mechanical preload of the gate valve sealing surface when there is no oil pressure, then the pressure F is calculated using the following formula:

[0068]

[0069] In the formula, K is the stiffness of the piezoelectric ceramic block; The piezoelectric constant of the piezoelectric ceramic block is 0.002C / N. This is the output voltage of the piezoelectric ceramic block.

[0070] In this embodiment, it is preferred =74.61N, K=100N / m, output voltage =2.5V, the compressive force is obtained through calculation. =74.11N.

[0071] Step 2: Calculate the radial displacement x of the SMA: For the potential leakage area, the required radial displacement x of the SMA is calculated based on the pressure F and the lattice Boltzmann analysis method.

[0072] The method for obtaining the Fx curve based on the lattice Boltzmann curve described above preferably includes the following steps.

[0073] Step 2-1: Based on the lattice Boltzmann method and the gate valve microchannel to be controlled, construct a micro-gap analysis and calculation model containing rough element features, set boundary conditions, and perform flow iteration until the flow field converges and the flow rate stabilizes. Preferably, the following steps are included.

[0074] Step 2-1A: Construct a two-dimensional computational domain containing symmetric rough elements based on the D2Q9 model, set the upper and lower walls of the micro-gap as solid boundaries, define the shape of the rough elements, mark the rough element regions as obstacles and apply a bounce format to achieve a slip-free boundary, and generate the flow mesh index and boundary coordinates.

[0075] In this embodiment, the dimensional parameters of the gate valve microchannel are defined as follows: the number of grids in the length direction is 250, the number of grids in the height direction is 40, and 5 pairs of triangular rough elements are set on each of the upper and lower walls. The rough element regions are marked as obstacles, and a bounce pattern is applied to achieve a slip-free boundary, generating a flow grid index and boundary coordinates. The bounce coefficient is 0.7, and the relaxation time is 1. Simultaneously, the preferred shape of the rough elements is triangular, based on the simulated inlet and outlet flow difference. Calculate the flow loss rate η of the microchannel:

[0076]

[0077] in:

[0078]

[0079] In the formula, Q in Q is the inflow of the computing region. out It is the outflow of the calculation area.

[0080] Step 2-1B: Based on the boundary coordinates, apply the Zou-He velocity boundary condition at the inlet to satisfy the average flow velocity constraint and the fixed inlet density. A Zou-He pressure boundary condition is applied at the outlet to achieve a constant outlet density. And reflux suppression.

[0081] Step 2-1C: At each time step, based on the Zou-He velocity boundary conditions and no-slip boundary conditions applied at the inlet and outlet, perform lattice Boltzmann iterations. This includes using the BGK model for the collision process and following the particle velocity directions and corresponding weighting coefficients defined by the D2Q9 model for the migration process. .

[0082] In this implementation case, The spatial step size and time step size are both 1.

[0083] Step 2-1D: Calculate the equilibrium distribution function of the lattice nodes based on the results of the iteration process. .

[0084] Step 2-1E, iteratively execute steps 2-1B and 2-1C, based on the Euclidean norm (L) of the current step density field and the previous step density field. 2 Relative error, relative error less than 10 -6 That is, the density field converges, based on the inlet flow rate Q. in and export flow Q out The change, with 5 consecutive flow rate changes less than 10 -4 Once the flow rate is stable, the calculation is complete.

[0085] In this implementation example, the inlet density is preferably 3.3, and the outlet density is preferably 3. The preferred size is 0.160311μm. 3 / s, Q out It is 0.141365μm 3 / s, the final flow field velocity distribution map is obtained, as shown Figure 7 As shown, the final traffic convergence history graph is obtained as follows: Figure 8 As shown, the percentage difference between inlet and outlet flow rates is as follows: Figure 9 As shown, the simulation results are as follows: =0.018946μm 3 / s, .

[0086] Step 2-2: Set all rough elements in the microchannel analysis model to the same height x. Use the momentum exchange method to calculate the instantaneous force at each boundary grid point. Calculate the change in the force exerted by the fluid on the rough element boundary before and after the collision to obtain the fluid extrusion force F borne by the rough element. Set the base of the triangular rough element and the distance between adjacent rough elements to constant values, only changing the rough element height, and compare the flow loss rate. The minimum value is the optimal sealing height of the triangular rough element.

[0087] In this embodiment, the preferred dimensions of the triangular rough element are: a base of 10 μm, a height of 5 μm, and a spacing of 30 μm between adjacent triangular rough elements. Specifically, as shown below... Figure 6 As shown.

[0088] The shape of the SMA in this invention is preferably triangular, and can be set according to the optimal sealing height, base dimension, and spacing of the triangular roughness element. That is, the initial thickness of the SMA adopts the optimal sealing height of the triangular roughness element. Secondly, the temperature deformation of the SMA can cause radial displacement, and the radial displacement value is equal to the different roughness element heights x in the simulation. Therefore, the Fx curve fitted by the simulation can be used directly.

[0089] In addition, during the calculation of fluid extrusion pressure F, after processing, the inlet and outlet flow rate difference corresponding to the height x of each rough element can be obtained. .

[0090] Step 2-3: Replace the roughness element height x in Step 2-2, and repeat Step 2-2 to obtain the Fx curve, specifically:

[0091]

[0092] In the formula, represents the simulation fitting coefficients, where i is the term number of the polynomial, with a value ranging from 0 to 7.

[0093] In this embodiment, the constructed Fx curve is preferably:

[0094] F=0.00005426 -0.002011 +0.02964 -0.2217 +0.8973 -1.945 +2.149x+72.95

[0095] In this embodiment, the extrusion pressure =74.11N, substituting into the fitted Fx curve above, we get x=5μm.

[0096] Furthermore, while changing the height x of each rough element and calculating the fluid extrusion pressure F, the corresponding inlet and outlet flow rate difference was recorded. Thus, it is also possible to obtain a fit. The curve, specifically:

[0097]

[0098] In the formula, for The simulation fitting coefficients are given by , where j is the term number of the polynomial, and its value ranges from 0 to 4.

[0099] In this embodiment, the constructed The curve, preferably:

[0100] =-0.005569 +0.3276x+0.01054

[0101] Step 3: Calculate the target heating temperature T required for the SMA based on the radial displacement x of the SMA. Preferably, the temperature T is calculated using the following formula:

[0102]

[0103] In the formula, This corresponds to the SMA length in the sealing block; This is the initial strain of the SMA; It is SMA stress; It is the phase transition modulus of SMA; Initial ambient temperature; It is the current martensite volume fraction Young's modulus of the lower SMA; This is the maximum recoverable strain of the SMA; It is the martensite volume fraction of SMA.

[0104] In this embodiment, L is 10 mm. When the shape memory alloy is subjected to extrusion, the stress... It is 59.5 MPa, material 0.55MPa·% -1 At this point, the martensite volume fraction Young's modulus It is 75 GPa. When the heating coil raises the temperature to the preset phase transition temperature of 65°C, When the SMA reaches its maximum displacement after heating is complete, its value is approximately 0. This indicates that the SMA expands due to thermal expansion, resulting in displacement. :

[0105]

[0106] That is, the radial displacement x of the SMA At 5μm, the target heating temperature is T=65℃.

[0107] Step 4: The heating component is activated, heating the SMA to the target heating temperature T calculated in Step 3. In this embodiment, due to the ambient temperature... Therefore, a temperature change is applied to the SMA at 25℃. .

[0108] Step 5: The temperature sensor monitors the temperature of the SMA in real time and maintains the SMA at the target heating temperature T=65℃. The PID temperature control accuracy in this invention is as follows: Figure 10 As shown.

[0109] Step 6: Calculate the valve seat flow loss rate The specific calculation formula is as follows:

[0110]

[0111] In the formula, This refers to the inlet flow rate of the gate valve microchannel; The radial displacement x of the SMA calculated in step 2; for The polynomial coefficient of the j-th term is equal to that in steps 2-3. In .

[0112] Step 7, Correcting the target heating temperature T: The piezoelectric ceramic block in the potential leak area detection continues to provide real-time feedback on the pressure F it is subjected to, and... Compare; if F < If the target heating temperature T is not reached, repeat steps 2 to 6 to adjust the target heating temperature T until F is reached. .

[0113] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all fall within the protection scope of the present invention.

Claims

1. A gate valve microchannel leakage prevention and control device, characterized in that: It is set on the inner wall of the gate valve microchannel, including a number of sealing blocks and heat insulation blocks that are evenly and alternately arranged along the circumference of one inner wall of the microchannel. Each sealing block includes a piezoelectric ceramic block, SMA, a temperature sensor, and a heating assembly; The bottom surface of the piezoelectric ceramic block is arranged on the inner wall of the microchannel; SMA is set on the top surface of the piezoelectric ceramic block; Temperature sensors are used to monitor the temperature of the SMA in real time; The heating element can heat the SMA.

2. The gate valve microchannel leakage prevention and control device according to claim 1, characterized in that: It also includes a PID controller, which is connected to the piezoelectric ceramic block, temperature sensor and heating assembly respectively.

3. The gate valve microchannel leakage prevention and control device according to claim 1, characterized in that: The piezoelectric ceramic block is fan-shaped with a central angle of 0~30°; the heating element is an electric heating coil, which is arranged between the piezoelectric ceramic block and the SMA.

4. A control method based on lattice Boltzmann, characterized in that: Includes the following steps: Step 1, Potential Leakage Area Detection: The piezoelectric ceramic block in each sealing block provides real-time feedback on the pressure F it bears, and compares the pressure F with the set piezoelectric ceramic compressive stress threshold. Compare; when F < If the leak occurs, the sealing surface area corresponding to the sealing block is determined to be a potential leakage area; otherwise, there is no leakage. Step 2: Calculate the radial displacement x of the SMA: For the potential leakage area, the required radial displacement x of the SMA is calculated based on the pressure F and the lattice Boltzmann analysis method. Step 3: Calculate the target heating temperature T required for the SMA based on the radial displacement x of the SMA; Step 4: The heating component is activated to heat the SMA to the target heating temperature T calculated in Step 3; Step 5: The temperature sensor monitors the temperature of the SMA in real time and keeps the SMA at the target heating temperature T.

5. The control method based on lattice Boltzmann as described in claim 4, characterized in that: In step 1, the piezoelectric ceramic is subjected to a pressure threshold. If the value is the mechanical preload of the gate valve sealing surface when there is no oil pressure, then the pressure F is calculated using the following formula: In the formula, K is the stiffness of the piezoelectric ceramic block; The piezoelectric constant of the piezoelectric ceramic block; This is the output voltage of the piezoelectric ceramic block.

6. The control method based on lattice Boltzmann as described in claim 4, characterized in that: In step 2, the Fx curve is obtained based on the lattice Boltzmann analysis method, and its specific expression is as follows: In the formula, represents the simulation fitting coefficients, where i is the term number of the polynomial, with a value ranging from 0 to 7.

7. The control method based on lattice Boltzmann as described in claim 6, characterized in that: Step 2, the method for obtaining the Fx curve based on the lattice Boltzmann algorithm, includes the following steps: Step 2-1: Based on the lattice Boltzmann method and the gate valve microchannel to be controlled, construct a micro-gap analysis and calculation model containing rough element features, set boundary conditions and perform flow iteration until the flow field converges and the flow rate stabilizes. Step 2-2: Set all rough elements in the micro-gap analysis calculation model to the same height x, use the momentum exchange method to calculate the instantaneous force at each boundary grid point, calculate the change of the fluid force on the rough element boundary before and after the collision, and obtain the fluid extrusion force F borne by the rough element. Step 2-3: Replace the roughness element height x in step 2-2, repeat step 2-2, and obtain the Fx curve.

8. The control method based on lattice Boltzmann as described in claim 6, characterized in that: It also includes step 6, calculating the valve seat flow loss rate. The specific calculation formula is as follows: In the formula, This refers to the inlet flow rate of the gate valve microchannel; Let x be the radial displacement of the SMA calculated in step 2; j is... The term number of the polynomial in the polynomial ranges from 0 to 4; for The polynomial coefficients of the j-th term are obtained through simulation fitting.

9. The control method based on lattice Boltzmann as described in claim 8, characterized in that: It also includes step 7, correcting the target heating temperature T: the piezoelectric ceramic block in the potential leak area detection continues to provide real-time feedback on the pressure F it is subjected to, and... Compare; if F < If the target heating temperature T is not reached, repeat steps 2 to 6 to adjust the target heating temperature T until F is reached. .

10. The control method based on lattice Boltzmann as described in claim 4, characterized in that: In step 3, the target heating temperature T is calculated using the following formula: In the formula, This corresponds to the SMA length in the sealing block; This is the initial strain of the SMA; It is SMA stress; It is the phase transition modulus of SMA; Initial ambient temperature; It is the current martensite volume fraction Young's modulus of the lower SMA; This is the maximum recoverable strain of the SMA; It is the martensite volume fraction of SMA.

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