A control method of a magnetic cilium array phase-locked pulse heat transport system

Abstract

The present application relates to the field of microfluidic thermal technology, and particularly relates to a control method of a magnetic cilium array phase-locked pulse heat transport system, comprising: obtaining a predicted mechanical movement phase of a flexible magnetic cilium unit and determining the resistance of a corresponding conductive heating unit based on a real-time magnetic field angle signal and a preset magnetic machine coupling model; obtaining an actual bending phase deviation of the corresponding flexible magnetic cilium unit; determining a corrected pulse heating trigger phase; and performing pulse activation according to the corrected pulse heating trigger phase, wherein the average heating power in the reverse stroke in the same swing cycle is less than the average heating power in the forward stroke. The present application predicts the cilium phase based on the magnetic machine coupling model, corrects the actual bending phase by using the resistance change, realizes the phase-locked control of the pulse heating trigger phase, matches the thermal excitation with the effective flow window, improves the heat transport efficiency and stability, reduces the heating power by using the reverse stroke, suppresses the invalid heat disturbance, and enhances the heat transport directionality.

Description

Technical Field

[0001] This invention relates to the field of microfluidic thermal control technology, specifically to a control method for a magnetic fibrous array phase-locked pulsed thermal transport system. Background Technology

[0002] In applications such as microfluidic chips, cell culture chips, targeted heat treatment, implantable thermal management devices, and microscale biological sample manipulation, it is often necessary to achieve gentle, controllable, and directional heat transport within a small space. Such systems are typically under low Reynolds number conditions, with weak fluid inertia and viscous effects dominating. The time-reversal symmetry of the flow significantly affects the net transport efficiency of fluid and heat.

[0003] Artificial magnetic cilia arrays are a typical type of microscale soft actuator. Driven by an external rotating magnetic field, oscillating magnetic field, or spatially varying magnetic field, flexible magnetic cilia can generate asymmetric oscillation or cooperative wave motion. Furthermore, by simply combining the magnetically driven cilia pumping structure with a continuous heating element, local flow, mixing, or pumping can be induced in low Reynolds number environments.

[0004] However, the phase of the external magnetic field is not consistent with the actual mechanical phase of the flexible magnetic fibers. Due to the influence of fluid viscous damping, material viscoelasticity and magnetoelastic coupling, the actual bending response is significantly delayed. If the heating pulse is triggered by the external magnetic field alone, it is easy to cause the heat release window and the effective flow window to be misaligned and the directional heat transport efficiency to be low. Summary of the Invention

[0005] (a) Purpose of the invention The purpose of this invention is to provide a control method for a magnetic cilia array phase-locked pulsed thermal transport system. Based on the magnetomechanical coupling model, the cilia phase is predicted, and the actual bending phase is corrected by the change in the resistance of the conductive layer. This achieves phase-locked control of the pulsed heating trigger phase, matching the thermal excitation with the effective push flow window, improving thermal transport efficiency and stability. At the same time, the reverse stroke is used to reduce the heating power, suppress ineffective thermal disturbances, and enhance the directionality of thermal transport.

[0006] (II) Technical Solution To address the above problems, this invention provides a control method for a magnetic fibrous array phase-locked pulsed heat transport system, comprising: Acquire the real-time magnetic field angle signal of the periodically changing magnetic field; Based on the real-time magnetic field angle signal and the preset magnetomechanical coupling model, the predicted mechanical motion phase of each flexible magnetic fibrous unit is obtained. At a preset time point, the resistance of the conductive heating unit corresponding to each flexible magnetic fiber unit is determined; Based on the resistance, the actual bending phase deviation corresponding to the flexible magnetic fiber unit is obtained; The corrected pulse heating trigger phase is determined based on the deviation between the predicted mechanical motion phase and the actual bending phase. According to the corrected pulse heating trigger phase, a pulse is applied to the conductive heating unit of the flexible magnetic fiber unit to activate heat transport. Among them, the average heating power in the reverse stroke within the same oscillation cycle is less than the average heating power in the forward stroke.

[0007] In another aspect of the present invention, preferably, the preset magnetomechanical coupling model is used to characterize the mechanical response characteristics of the flexible magnetic fiber unit under the action of a periodically changing magnetic field; The magnetomechanical coupling model is an analytical model established based on the dynamic equations or a phase lookup table obtained through experimental calibration.

[0008] In another aspect of the present invention, preferably, the predicted mechanical motion phase of each flexible magnetic fiber unit is obtained based on the real-time magnetic field angle signal and a preset magnetomechanical coupling model, including: When the magnetomechanical coupling model is an analytical model based on dynamic equations, the predicted mechanical motion phase is obtained through the following steps; Obtain the magnetic field angle information corresponding to the periodically changing magnetic field at the current moment; Based on the magnetic field angle information, determine the magnetic driving torque corresponding to each flexible magnetic fiber unit; Based on the magnetic driving torque, and combined with the elastic recovery characteristics and fluid damping characteristics of the flexible magnetic fibrous unit, the theoretical oscillation state of each flexible magnetic fibrous unit is obtained. Based on the array interaction relationship between adjacent or similar flexible magnetic fiber units in the array, the theoretical oscillation state is phase-coupled and corrected. Based on the corrected theoretical oscillation state, the predicted mechanical motion phase of each flexible magnetic fiber unit in the current oscillation period is obtained. When the magnetomechanical coupling model is a phase lookup table, the corresponding predicted mechanical motion phase is obtained by looking up the table based on the current magnetic field angle information.

[0009] In another aspect of the present invention, preferably, determining the resistance of the conductive heating unit corresponding to the flexible magnetic fiber unit at a preset time node includes: At a preset time point, the electrical signals of the branch of the conductive heating unit are collected, and the electrical signals are voltage signals and current signals; Calculate the resistance of the conductive heating unit based on the voltage and current signals; The preset time point is either before heating is triggered or at the beginning of heating.

[0010] In another aspect of the present invention, preferably, obtaining the actual bending phase deviation of the flexible magnetic fiber unit based on the resistance includes: Based on the resistor and the reference resistor, the relative resistance change rate of the conductive heating unit is obtained; Based on the relative resistance change rate and the preset resistance micro-change-bending phase mapping relationship, the actual bending phase deviation corresponding to the flexible magnetic fiber unit is obtained.

[0011] In another aspect of the present invention, preferably, determining the corrected pulse heating trigger phase based on the deviation between the predicted mechanical motion phase and the actual bending phase includes: The phase compensation amount is calculated based on the actual bending phase deviation and the preset compensation relationship; Based on the predicted mechanical motion phase, phase compensation amount, and preset lead phase angle, the corrected pulse heating trigger phase is determined; The preset compensation relationship includes at least one of a proportional compensation relationship, a periodic update relationship, or a compensation lookup table; the preset lead phase angle is used to compensate for the mechanical response hysteresis generated by the flexible magnetic fiber unit in a fluid viscous damping and / or viscoelastic environment.

[0012] In another aspect of the present invention, preferably, the modified pulse heating trigger phase is calculated using the following formula: in, This indicates the corrected pulse heating trigger phase. Indicates the predicted mechanical motion phase. The preset lead phase angle, This is the phase compensation amount.

[0013] In another aspect of the present invention, preferably, the step of pulse activation of the conductive heating unit of the flexible magnetic fiber unit for heat transport according to the modified pulse heating trigger phase includes: Based on the corrected pulse heating trigger phase, the conductive heating units of different flexible magnetic fiber units are activated by time-division pulses within one oscillation cycle. By activating the time-division pulse, thermally excited regions are generated sequentially between adjacent or nearby flexible magnetic fiber units, forming localized thermal microclusters that migrate along the target transport direction. The pulse heating parameters for pulse activation are determined based on a preset parameter determination mechanism. Based on the pulse heating parameters, pulse activation is performed within the current oscillation cycle; Collect feedback information on the local temperature rise region within the current oscillation cycle. The feedback information includes at least one of the following: the location, area, peak temperature rise, centroid migration direction, centroid migration speed, and accumulated heat in the downstream region of the local temperature rise region. The pulse heating parameters are updated based on the deviation between the feedback information and the preset target temperature rise threshold, preset target migration direction, or preset target migration speed. Based on the updated pulse heating parameters, the conductive heating unit in the subsequent oscillation cycle is pulse-activated.

[0014] In another aspect of the present invention, preferably, the step of pulse activation within the current oscillation cycle based on the pulse heating parameters includes: Based on the pulse heating parameters, pulse activation is performed within the forward stroke of the current oscillation cycle, wherein the pulse heating parameters include heating current; During the reverse stroke within the current oscillation cycle, the heating current is reduced so that the average heating power during the reverse stroke is less than the average heating power during the forward stroke.

[0015] In another aspect of the present invention, preferably, the preset parameter determination mechanism includes determining the pulse heating parameters for pulse activation based on at least one of the preset target temperature rise threshold, fluid thermal diffusivity, conductive heating unit heat capacity, ciliary oscillation period, and forward thrust work stroke duration.

[0016] (III) Beneficial Effects The above-described technical solution of the present invention has the following beneficial technical effects: This invention acquires the real-time angle signal of the periodically changing magnetic field and predicts the mechanical motion phase of each flexible magnetic fiber unit using a magnetomechanical coupling model. Simultaneously, it introduces the resistance change of the conductive heating unit during the periodic bending process as feedback information to reflect the actual bending state of the fibers, thereby obtaining the actual bending phase deviation. Based on this, the predicted phase and the actual phase deviation are fused and corrected to obtain a more accurate pulse heating trigger phase. This achieves a lock-in match between the heating pulse and the effective flow window of the fibers, reducing heat release misalignment caused by phase lag and improving heat transport efficiency and stability. Furthermore, by reducing the average heating power of the reverse stroke within the same oscillation cycle and increasing the energy proportion of the forward stroke, ineffective reverse thermal disturbances are suppressed, further enhancing the directional selectivity and net transport capacity of heat transport, thus achieving efficient and stable phase-locked pulse heat transport control. Attached Figure Description

[0017] Figure 1 This is an overall flowchart of one embodiment of the present invention; Figure 2 This is a schematic diagram of the overall structure of one embodiment of the present invention; Figure 3 This is a schematic diagram of the timing relationship according to an embodiment of the present invention; Figure 4 This is a schematic diagram comparing one embodiment of the present invention with a comparative example of heat transport modes; Figure label: 100: Circuit substrate; 101: Electrical connection branch; 200: Flexible magnetic fiber unit 300: Conductive heating unit, 400: Magnetic field generating unit 500: Control unit. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0019] The accompanying drawings show structural schematic diagrams according to embodiments of the present invention. These drawings are not drawn to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0020] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0021] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0022] The invention will now be described in more detail with reference to the accompanying drawings. In the various drawings, the same elements are indicated by similar reference numerals. For clarity, the various parts in the drawings are not drawn to scale.

[0023] Example 1 A control method for a magnetic fibrous array phase-locked pulse thermal transport system. Figure 1 An overall flowchart of one embodiment of the present invention is shown. Figure 2 This is a schematic diagram of the overall structure of one embodiment of the present invention, as shown below. Figure 1and Figure 2 As shown, the magnetic fibrous array phase-locked pulse thermal transport system includes a circuit substrate, flexible magnetic fibrous units, conductive heating units, a magnetic field generating unit, and a control unit. Multiple flexible magnetic fibrous units are arranged on the circuit substrate, and the flexible magnetic fibrous units and conductive heating units are connected. The circuit substrate serves as a support platform, on which multiple independent electrical connection branches are set for supplying power and transmitting control signals to different flexible magnetic fibrous units and conductive heating units, enabling independent or group control of each flexible magnetic fibrous unit and conductive heating unit. The control unit can rapidly and intermittently pulse-heat a nearby local area through the conductive heating unit, thereby changing the local temperature field. The magnetic field generating unit generates a periodically changing external magnetic field. Under the control of the control unit, the magnetic field drives the flexible magnetic fibrous units to oscillate regularly, forming controllable motion in space. The flexible magnetic fibrous units have a magnetization orientation angle that varies along the target transport direction, or there is a preset magnetization phase difference between adjacent flexible magnetic fibrous units. When an external periodically changing magnetic field is applied to the array, multiple flexible magnetic fibers of roughly equal length generate bending responses with a phase sequence at different positions, thus forming a coordinated wave-like oscillation. This coordinated wave-like oscillation includes a forward thrust stroke and a reverse return stroke.

[0024] like Figure 1 As shown, the control method specifically includes: The real-time magnetic field angle signal of the periodically changing magnetic field is obtained. The periodically changing magnetic field is generated by the magnetic field generating unit. The periodically changing magnetic field drives the flexible magnetic fiber unit to swing. The real-time magnetic field angle signal is used to characterize the instantaneous direction and change state of the external driving magnetic field within one swing cycle. The real-time magnetic field angle signal can be obtained by the magnetic field generating unit, either directly or by the control unit calculating the corresponding information from the magnetic field generating unit. The magnetic field generating unit can be a rotating permanent magnet, a Heilbeck array, a Helmholtz coil, a triaxial electromagnetic coil, an array electromagnetic coil, or other devices capable of generating a periodically changing magnetic field.

[0025] Based on the real-time magnetic field angle signal and the preset magnetomechanical coupling model, the predicted mechanical motion phase of each flexible magnetic fiber unit is obtained. The predicted mechanical motion phase is a process of feedforward estimation of the dynamic response of each flexible magnetic fiber unit under magnetic field drive. Its purpose is to predict the oscillation state of each flexible magnetic fiber unit within one oscillation cycle before actual thermal excitation, thereby providing a reference for subsequent phase-locked pulse control.

[0026] A pre-defined magnetomechanical coupling model is used to characterize the mechanical response characteristics of the flexible magnetic fibrous unit under the action of a periodically changing magnetic field. The magnetomechanical coupling model is either an analytical model based on dynamic equations or a phase lookup table obtained through experimental calibration. The analytical model based on dynamic equations includes simplified relationships between magnetic torque, elastic restoring force, fluid viscous drag, and array interactions. When the magnetomechanical coupling model is an analytical model based on dynamic equations, the predicted mechanical motion phase is obtained through the following steps. Obtain the magnetic field angle information corresponding to the periodically changing magnetic field at the current moment; Based on the magnetic field angle information, the magnetic driving torque corresponding to each flexible magnetic fibrous unit is determined. Since the flexible magnetic fibrous unit has a magnetic material layer or magnetic response structure, it will generate a magnetic torque drive under the action of an external magnetic field. The magnitude of the torque drive is closely related to the magnetic field strength, magnetization, and the angle between the magnetic moment direction and the magnetic field direction. Furthermore, based on the vector cross product relationship or the equivalent magnetic torque expression, the magnetic field angle information is converted into the instantaneous driving torque acting on each flexible magnetic fibrous unit, thereby obtaining the force input of each flexible magnetic fibrous unit at the current moment.

[0027] Based on the magnetic driving torque, and combining the elastic recovery characteristics and fluid damping characteristics of the flexible magnetic fiber unit, the theoretical oscillation state of each flexible magnetic fiber unit is obtained. The elastic recovery characteristics are used to describe the inherent stiffness of the flexible magnetic fiber returning to its initial shape after being bent under force, while the fluid damping characteristics are used to describe the viscous resistance it experiences when moving in the surrounding medium. By establishing an equivalent dynamic model, the flexible magnetic fiber unit can be equivalent to a damped elastic oscillator or flexible beam structure driven by the magnetic torque. By solving its motion equations, the theoretical oscillation states such as angular displacement, angular velocity, or oscillation trajectory are obtained, thus reflecting its dynamic response under ideal independent conditions.

[0028] Based on the array interaction relationships between adjacent or nearby flexible magnetic fiber units in the array, the theoretical oscillation state is corrected by phase coupling. Since multiple flexible magnetic fiber units are spatially arrayed, they may influence each other during oscillation through fluid disturbances, local magnetic field distortions, or mechanical coupling, resulting in actual phase deviations from the unit's independent response. In this embodiment, a coupling term is introduced to correct the theoretical oscillation state. For example, neighborhood weighted averaging, coupling stiffness correction terms, or phase synchronization constraint terms are used to correct the phase evolution of each flexible magnetic fiber unit, reflecting the overall cooperative motion characteristics.

[0029] Based on the corrected theoretical oscillation state, the predicted mechanical motion phase of each flexible magnetic fibrous unit in the current oscillation cycle is obtained. The mechanical motion phase represents the phase progress position of each flexible magnetic fibrous unit in a complete oscillation cycle.

[0030] When the magnetomechanical coupling model is a phase lookup table, the corresponding predicted mechanical motion phase is obtained by looking up the table based on the current magnetic field angle information. Rapid retrieval and interpolation calculations can be performed based on the mapping relationships in the phase lookup table, thereby directly converting the current magnetic field input into the corresponding predicted mechanical motion phase.

[0031] At a preset time point, the resistance of the conductive heating unit corresponding to each flexible magnetic fiber unit is determined. The conductive heating unit includes a metal nanowire network, a conductive polymer, a metal thin film, a carbon-based conductive network, or a composite structure thereof. Further, the conductive heating unit is a strain-stabilized conductive thin film formed by combining a silver nanowire network and a flexible polymer. The preset time point here is before heating triggering or in the initial stage of heating. There is a coupling relationship between the resistance of the conductive heating unit and the deformation state; therefore, the actual bending state of the flexible magnetic fiber unit can be reflected by the change in resistance. In this embodiment, it includes: At preset time points, electrical signals from the branches of the conductive heating unit are acquired, including voltage and current signals. The conductive heating unit simultaneously functions as a Joule heating output element and a resistive deformation phase feedback element. The resistance of the conductive heating layer is acquired during low-energy test pulses or at the beginning of high-level heating periods, and the pulse heating trigger phase is updated in each driving cycle, every few driving cycles, or when the phase error exceeds a preset threshold. The voltage signal across the conductive heating unit is acquired through a voltage sampling unit, and the current signal flowing through the branches of the conductive heating unit is acquired through a current sampling unit, forming synchronously sampled electrical parameter data.

[0032] The resistance of the conductive heating unit is calculated based on the voltage and current signals. This calculation can be based on Ohm's law; that is, ignoring transient noise and high-frequency disturbances, the ratio of the acquired instantaneous voltage to the current is calculated to obtain the equivalent resistance value at the corresponding moment.

[0033] Based on the resistance, the actual bending phase deviation corresponding to the flexible magnetic fiber unit is obtained, including: The relative resistance change rate of the conductive heating unit is obtained based on the resistance and the reference resistance. The reference resistance can be the baseline resistance value of the conductive heating unit corresponding to the flexible magnetic fiber unit in its initial unbent state or at a calibrated temperature. By calculating the ratio of the current resistance change to the reference resistance, the influence of individual differences and environmental drift can be eliminated, making the resistance change more accurately reflect the structural state change.

[0034] Based on the relative resistance change rate and the preset resistance micro-change-bending phase mapping relationship, the actual bending phase deviation corresponding to the flexible magnetic fiber unit is obtained. The resistance micro-change-bending phase mapping relationship is used to establish the correspondence between the small resistance change of the conductive heating unit and the mechanical bending phase of the flexible magnetic fiber unit. The resistance micro-change-bending phase mapping relationship is obtained through one or more of the following methods: microscopic imaging, particle image velocimetry, finite element-fluid-structure interaction simulation, and offline calibration experiments. That is, the resistance change is measured under different known bending angles or phase states, and a functional relationship or piecewise mapping curve is fitted. In this embodiment, the sheet resistance of the conductive heating unit can be designed according to the target heating power, for example, from 0.1 ohms per square to 500 ohms per square, taking into account both heating stability and phase feedback sensitivity. This allows the conductive heating unit to have repeatable and calibrable resistance changes within the bending range, while avoiding excessive Joule heat power fluctuations caused by resistance changes. The relative resistance change rate of the conductive heating unit within the set bending range is less than or equal to 10%; furthermore, in the dynamic bending cycle near the maximum bending state, the relative resistance change rate of the conductive heating unit is less than or equal to 5%. When the conductive heating unit maintains a small resistance change amplitude within a large bending range, its resistance signal will not experience drastic nonlinear fluctuations due to excessive deformation. This ensures that the resistance change and bending state maintain an approximately monotonic or weakly nonlinear relationship, thus facilitating the calibrability and repeatability of the resistance micro-change-bending phase mapping relationship. In this embodiment, the resistance micro-change-bending phase mapping relationship is obtained through the following steps: placing the flexible magnetic fiber unit in a target fluid or a calibration fluid with a viscosity close to that of the target fluid. Applying one or more periodically varying magnetic fields of different frequencies, amplitudes, and directions through a magnetic field generating unit to cause the flexible magnetic fiber unit to oscillate periodically. During calibration, the external magnetic field angle signal, the microscopic image of the flexible magnetic fiber unit, and the voltage and current signals of the electrical connection branch where the conductive heating unit is located are recorded simultaneously. The bending profile, endpoint displacement, root angle, curvature distribution, or other parameters characterizing the mechanical phase of the flexible magnetic fiber unit are obtained through microscopic image processing. The mechanical phase can be defined as the phase of the fiber endpoint in one cycle, or as the phase of the fiber root angle, average curvature, or maximum curvature. The instantaneous resistance of the conductive heating unit is calculated based on the collected voltage and current signals to obtain the relative resistance change rate. This relative resistance change rate is then fitted, looked up in a table, or modeled using machine learning to obtain the resistance micro-change-bending phase mapping relationship. This resistance micro-change-bending phase mapping relationship can be an analytical function, a lookup table, a piecewise linear function, a polynomial function, or a neural network model.

[0035] The corrected pulse heating trigger phase is determined based on the predicted mechanical motion phase and the actual bending phase deviation, including: calculating a phase compensation amount based on the actual bending phase deviation and a preset compensation relationship; and determining the corrected pulse heating trigger phase based on the predicted mechanical motion phase, the phase compensation amount, and a preset lead phase angle. The preset lead phase angle is used to compensate for the mechanical response hysteresis generated by the flexible magnetic fiber unit in fluid viscous damping and / or viscoelastic environments.

[0036] Specifically, in one implementation, the control unit uses the voltage signal of the branch where the conductive heating unit is located. and current signal Calculate instantaneous resistance ,Right now And according to the reference resistor Calculate the rate of change of relative resistance ,in Reference resistor It can be the resistance of the conductive heating unit of the flexible magnetic fiber unit in the initial unbent state, the calibrated temperature state, or the previous stable cycle.

[0037] In one implementation, a preset resistance change-bending phase mapping relationship is used based on the relative resistance change rate. Obtain the actual bending phase of the flexible magnetic fibrous unit ,Right now ,in This represents the mapping relationship established through offline calibration, lookup tables, piecewise functions, fitting functions, or machine learning models. The control unit will then transmit the actual bending phase. Phase with predicted mechanical motion By comparison, the actual bending phase deviation can be obtained. ,Right now .

[0038] In another implementation, the preset resistance micro-change-bending phase mapping relationship can also directly output the actual bending phase deviation. ,Right now ,in This indicates the calibration mapping relationship established based on the relative resistance change rate and the predicted mechanical motion phase.

[0039] The control unit based on the actual bending phase deviation Calculate phase compensation amount In one embodiment, the phase compensation amount is obtained through a proportional compensation relationship, i.e. ,in The compensation coefficient is a preset or calibrated value. In another embodiment, the phase compensation amount is obtained through a compensation lookup table, i.e., based on the actual bending phase deviation. The corresponding phase compensation amount is obtained by querying the pre-stored phase compensation lookup table. .

[0040] In another embodiment, the phase compensation amount is obtained using a cycle-by-cycle update method. For the nth oscillation cycle, the control unit calculates the actual bending phase deviation based on that cycle. Update the phase compensation amount to meet the requirements. ,in The proportional update coefficient is obtained through pre-setting or calibration. Optionally, the phase compensation amount is set with an upper limit and a lower limit to avoid compensation overshoot or triggering phase out-of-bounds errors.

[0041] Figure 3 A timing relationship diagram of an embodiment of the present invention is shown, as follows: Figure 3 As shown, the corrected pulse heating trigger phase has a preset leading phase angle relative to the peak shear rate phase of the flexible magnetic fibrous unit during the forward flow work stroke. This preset leading phase angle is used to compensate for the mechanical response hysteresis of the flexible magnetic fibrous unit in fluid viscous damping and / or viscoelastic environments. The preset leading phase angle is 1 degree to 20 degrees; further, it is 3 degrees to 12 degrees. This allows the conductive heating unit to enter the heating state before the flexible magnetic fibrous unit reaches its maximum shear rate, thereby modulating the local temperature field and fluid viscosity distribution in advance, and thus reducing the fluid resistance in the subsequent forward flow stage. The corrected pulse heating trigger phase is calculated using the following formula: in, This indicates the corrected pulse heating trigger phase. Indicates the predicted mechanical motion phase. The preset lead phase angle, This is the phase compensation amount.

[0042] According to the corrected pulse heating trigger phase, pulse activation is performed on the conductive heating unit of the flexible magnetic fiber unit to carry out heat transport, including: Based on the corrected pulse heating trigger phase, the conductive heating units of different flexible magnetic fibrous units are activated by time-division pulses within one oscillation cycle. Pulse on / off control is executed sequentially or in groups on multiple pre-divided flexible magnetic fibrous units, so that each conductive heating unit is activated sequentially within different time windows, thereby forming a transient heat source sequence with a phase gradient distribution in space. Through the time-division pulse activation, thermal excitation regions are sequentially generated between adjacent or nearby flexible magnetic fibrous units, forming localized thermal microclusters that migrate along the target transport direction. According to a preset parameter determination mechanism, the pulse heating parameters for pulse activation are determined. In this embodiment, the preset parameter determination mechanism includes determining the pulse heating parameters based on at least one of a preset target temperature rise threshold, the fluid thermal diffusivity, the heat capacity of the conductive heating unit, the ciliary oscillation period, and the duration of the forward thrust stroke. For example, the pulse heating parameters also include at least one of the amplitude, pulse width, frequency, and duty cycle of the pulse heating current. At least one of the amplitude, pulse width, frequency, and duty cycle of the pulse heating current is adjusted according to the target temperature rise threshold so that the local temperature rise area formed by a single pulse in the surrounding fluid does not exceed the target temperature rise threshold. The target temperature rise threshold can be set according to the application. For example, for temperature-sensitive samples, the target temperature rise threshold can be set to no more than 60 degrees Celsius, or it can be set to no more than 45 degrees Celsius, 42 degrees Celsius, or other temperatures according to stricter biosafety requirements. In this embodiment, the target temperature rise threshold is between 20 degrees Celsius and 60 degrees Celsius; further, the target temperature rise threshold does not exceed 60 degrees Celsius. The control unit can estimate the local temperature rise caused by a single pulse based on the resistance of the conductive heating unit, the input power, the local fluid thermal diffusivity, the ciliary oscillation period, and the duration of the forward thrust stroke.

[0043] Based on the pulse heating parameters, pulse activation is performed within the current oscillation cycle; Feedback information on the localized temperature rise region within the current oscillation cycle is collected. This can be achieved through one or more methods, such as thermosensitive fluorescence imaging, infrared microthermometry, temperature coefficient of resistance measurement, or a miniature temperature sensor array, to obtain the location, area, peak temperature rise, and migration speed of the localized temperature rise region. For example, if the localized temperature rise region is measured using a thermosensitive fluorescent dye, the thermosensitive fluorescence intensity changes with temperature, and the control unit can obtain the location, area, peak temperature rise, and migration speed of the localized temperature rise region based on the fluorescence image. Alternatively, temperature feedback can be obtained through infrared microthermometry, temperature coefficient of resistance measurement, or a miniature temperature sensor array. Updated pulse heating parameters are then determined based on this feedback information. Specifically, when the peak temperature rise of the local temperature rise region is detected to be close to or exceed the target temperature rise threshold, the control unit reduces the pulse heating current amplitude, shortens the pulse width, reduces the duty cycle, or increases the interval time between adjacent pulses in subsequent oscillation cycles to reduce local heat accumulation; when the centroid migration speed of the local temperature rise region along the target direction is detected to be lower than the preset target migration speed, and the peak temperature rise is lower than the target temperature rise threshold, the control unit increases the pulse heating current amplitude, extends the pulse width, increases the duty cycle, or adjusts the pulse heating trigger phase, under the condition that it does not exceed the target temperature rise threshold, to enhance the formation of local thermal microclusters and migration in the target direction; when the local temperature rise region is detected to deviate from the target transport direction, the control unit adjusts the trigger time, phase delay, or time-division activation sequence of the conductive heating units corresponding to adjacent or nearby flexible magnetic fiber units to correct the migration direction of the local thermal microclusters.

[0044] Based on the updated pulse heating parameters, the conductive heating unit in the subsequent oscillation cycle is pulse-activated.

[0045] Furthermore, in this embodiment, the step of pulse activation within the current oscillation cycle based on the pulse heating parameters includes: Based on the pulse heating parameters, pulse activation is performed during the forward stroke of the current oscillation cycle, where the pulse heating parameters include the heating current. During the reverse stroke of the current oscillation cycle, the heating current is reduced so that the average heating power during the reverse stroke is less than the average heating power during the forward stroke. That is, the average heating power during the reverse stroke is less than the average heating power during the forward stroke within the same oscillation cycle. The average power of the pulse heating current during the reverse stroke is less than 20% of the average power during the forward stroke; further, the average power during the reverse stroke is less than 10% of the average power during the forward stroke. When the corrected pulse heating trigger phase is reached, the control unit outputs a high-level pulse heating current to the corresponding conductive heating unit. The high-level heating period is configured to primarily occur within the forward push-flow work stroke. As the forward stroke is established, the localized temperature rise region formed near the conductive heating unit is sheared and stripped by the flow field and migrates towards the target direction. When the flexible magnetic fiber unit enters the reverse stroke, the control unit switches the conductive heating layer to a power-off state or a low-power state. Thus, no new heat injection of the same intensity is generated during the reverse stroke, thereby reducing the reverse heat carryover and localized heat accumulation during the reverse stroke.

[0046] In this embodiment, within a large-area flexible magnetic fiber unit array, flexible magnetic fiber units at different locations may be in different mechanical phases due to variations in magnetization orientation, local fluid damping, or array coupling. To improve the array-scale heat transport effect, multiple flexible magnetic fiber units can be divided into multiple phase regions. Each phase region has an independent electrical connection branch and an independent pulse heating output channel. The control unit calculates the predicted mechanical motion phase for each phase region and acquires the resistance micro-change signal of the corresponding conductive heating layer's branch. Subsequently, the control unit determines the corrected pulse heating trigger phase for each phase region, matching the heat input window of each phase region with its local forward thrust work stroke. In this way, the local temperature rise regions generated by multiple phase regions can spatially migrate sequentially, thereby forming a more continuous target-direction heat transport.

[0047] The magnetic fibrous array was placed in a microfluidic channel, and under the same external magnetic field frequency, magnetic field strength, fluid viscosity and total input energy, the continuous heating mode, the open-loop pulse heating mode and the heating mode of this embodiment were compared.

[0048] Continuous heating mode refers to the conductive heating layer being continuously energized throughout the entire cilia oscillation cycle or heated in a manner that does not distinguish between forward and return strokes. Open-loop pulse heating mode refers to pulse heating triggered by a preset magnetic field phase, but without collecting the small resistance change signal of the conductive heating layer for phase correction. The heating mode in this embodiment refers to determining the heating trigger phase based on prediction by the magnetomechanical model and feedback correction of small resistance changes, and cutting off power or reducing power during the return stroke.

[0049] The target-direction time-averaged net heat flux can be calculated using temperature and velocity fields, or indirectly characterized by the centroid displacement of the local temperature rise region, the attenuation of peak temperature rise, and the change in accumulated heat in the downstream region. For two-dimensional microscopic observation, the local temperature rise region can be defined as the area where the temperature rise exceeds 50% of the peak temperature rise or exceeds a preset temperature rise threshold, and the centroid displacement direction and velocity of this region in multiple cycles are recorded. In specific experiments or simulation evaluations, under the same total input energy, the same external magnetic field frequency, the same magnetic field strength, the same fluid viscosity, and the same observation time window, the target-direction time-averaged net heat flux, the centroid migration velocity of the local temperature rise region, the change in accumulated heat in the downstream region, and the peak temperature rise attenuation characteristics corresponding to the continuous heating mode, the open-loop pulse heating mode, and the phase-locked pulse heating mode of this embodiment can be obtained respectively, and the directional heat transport effects of different heating modes can be compared accordingly. In this embodiment, by matching the pulse heating trigger phase with the forward thrust work stroke of the flexible magnetic fiber unit, and reducing the heating power or switching to a low-power state in the reverse stroke, the ineffective heat injection and heat backmixing in the reverse stroke are reduced. After obtaining the corresponding experimental or simulation results, the degree of improvement in heat transport in this embodiment relative to the comparative example can be determined based on the above evaluation indicators. Figure 4 A schematic diagram comparing an embodiment of the present invention with a comparative example of heat transport modes is shown; as follows: Figure 4 As shown in Figure a, continuous heating leads to heat dispersion and heat remixing. Figure 4 Figure b illustrates the process by which localized thermal microclusters are generated through time-division pulse activation and migrate directionally along the target direction in this embodiment. This embodiment exhibits less thermal dispersion and thermal backmixing, achieving efficient and controllable directional thermal transport.

[0050] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

[0051] The above description does not provide detailed explanations of the technical aspects of each layer's patterning and etching. However, those skilled in the art should understand that various methods existing in the prior art can be used to form layers and regions of the desired shape. Furthermore, to form the same structure, those skilled in the art can also design methods that are not entirely identical to those described above.

[0052] The present invention has been described above with reference to embodiments thereof. However, these embodiments are merely illustrative and not intended to limit the scope of the invention. The scope of the invention is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the invention, and all such substitutions and modifications should fall within the scope of the invention.

[0053] Although embodiments of the present invention have been described in detail, it should be understood that various changes, substitutions, and modifications can be made to the embodiments of the present invention without departing from the spirit and scope of the invention.

[0054] Obviously, the above embodiments are merely illustrative examples for clear explanation 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 here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A control method for a magnetic fibrous array phase-locked pulse thermal transport system, characterized in that, include: Acquire the real-time magnetic field angle signal of the periodically changing magnetic field; Based on the real-time magnetic field angle signal and the preset magnetomechanical coupling model, the predicted mechanical motion phase of each flexible magnetic fibrous unit is obtained. At a preset time point, the resistance of the conductive heating unit corresponding to each flexible magnetic fiber unit is determined; Based on the resistance, the actual bending phase deviation corresponding to the flexible magnetic fiber unit is obtained; The corrected pulse heating trigger phase is determined based on the deviation between the predicted mechanical motion phase and the actual bending phase. According to the corrected pulse heating trigger phase, a pulse is applied to the conductive heating unit of the flexible magnetic fiber unit to activate heat transport. Among them, the average heating power in the reverse stroke within the same oscillation cycle is less than the average heating power in the forward stroke.

2. The control method for the magnetic fiber array phase-locked pulse heat transport system according to claim 1, characterized in that, The preset magnetomechanical coupling model is used to characterize the mechanical response characteristics of the flexible magnetic fiber unit under the action of a periodically changing magnetic field. The magnetomechanical coupling model is an analytical model established based on the dynamic equations or a phase lookup table obtained through experimental calibration.

3. The control method for the magnetic fiber array phase-locked pulse heat transport system according to claim 2, characterized in that, Based on the real-time magnetic field angle signal and the preset magnetomechanical coupling model, the predicted mechanical motion phase of each flexible magnetic fiber unit is obtained, including: When the magnetomechanical coupling model is an analytical model based on dynamic equations, the predicted mechanical motion phase is obtained through the following steps; Obtain the magnetic field angle information corresponding to the periodically changing magnetic field at the current moment; Based on the magnetic field angle information, determine the magnetic driving torque corresponding to each flexible magnetic fiber unit; Based on the magnetic driving torque, and combined with the elastic recovery characteristics and fluid damping characteristics of the flexible magnetic fibrous unit, the theoretical oscillation state of each flexible magnetic fibrous unit is obtained. Based on the array interaction relationship between adjacent or similar flexible magnetic fiber units in the array, the theoretical oscillation state is phase-coupled and corrected. Based on the corrected theoretical oscillation state, the predicted mechanical motion phase of each flexible magnetic fiber unit in the current oscillation period is obtained. When the magnetomechanical coupling model is a phase lookup table, the corresponding predicted mechanical motion phase is obtained by looking up the table based on the current magnetic field angle information.

4. The control method for the magnetic fiber array phase-locked pulse heat transport system according to claim 1, characterized in that, The step of determining the resistance of the conductive heating unit corresponding to the flexible magnetic fiber unit at a preset time node includes: At a preset time point, the electrical signals of the branch of the conductive heating unit are collected, and the electrical signals are voltage signals and current signals; Calculate the resistance of the conductive heating unit based on the voltage and current signals; The preset time point is either before heating is triggered or at the beginning of heating.

5. The control method for the magnetic fiber array phase-locked pulse heat transport system according to claim 1, characterized in that, The step of obtaining the actual bending phase deviation of the flexible magnetic fiber unit based on the resistance includes: Based on the resistor and the reference resistor, the relative resistance change rate of the conductive heating unit is obtained; Based on the relative resistance change rate and the preset resistance micro-change-bending phase mapping relationship, the actual bending phase deviation corresponding to the flexible magnetic fiber unit is obtained.

6. The control method for the magnetic fiber array phase-locked pulse heat transport system according to claim 1, characterized in that, The step of determining the corrected pulse heating trigger phase based on the deviation between the predicted mechanical motion phase and the actual bending phase includes: The phase compensation amount is calculated based on the actual bending phase deviation and the preset compensation relationship; Based on the predicted mechanical motion phase, the phase compensation amount, and the preset lead phase angle, the corrected pulse heating trigger phase is determined; The preset compensation relationship includes at least one of a proportional compensation relationship, a periodic update relationship, or a compensation lookup table; the preset lead phase angle is used to compensate for the mechanical response hysteresis generated by the flexible magnetic fiber unit in a fluid viscous damping and / or viscoelastic environment.

7. The control method for the magnetic fiber array phase-locked pulse heat transport system according to claim 6, characterized in that, The corrected pulse heating trigger phase is calculated using the following formula: in, This indicates the corrected pulse heating trigger phase. Indicates the predicted mechanical motion phase. The preset lead phase angle, This is the phase compensation amount.

8. The control method for the magnetic fiber array phase-locked pulse heat transport system according to claim 1, characterized in that, The step of pulse activation of the conductive heating unit of the flexible magnetic fiber unit according to the corrected pulse heating trigger phase for heat transport includes: Based on the corrected pulse heating trigger phase, the conductive heating units of different flexible magnetic fiber units are activated by time-division pulses within one oscillation cycle. By activating the time-division pulse, thermally excited regions are generated sequentially between adjacent or nearby flexible magnetic fiber units, forming localized thermal microclusters that migrate along the target transport direction. The pulse heating parameters for pulse activation are determined based on a preset parameter determination mechanism. Based on the pulse heating parameters, pulse activation is performed within the current oscillation cycle; Collect feedback information on the local temperature rise region within the current oscillation cycle. The feedback information includes at least one of the following: the location, area, peak temperature rise, centroid migration direction, centroid migration speed, and accumulated heat in the downstream region of the local temperature rise region. The pulse heating parameters are updated based on the deviation between the feedback information and the preset target temperature rise threshold, preset target migration direction, or preset target migration speed. Based on the updated pulse heating parameters, the conductive heating unit in the subsequent oscillation cycle is pulse-activated.

9. The control method for the magnetic fiber array phase-locked pulse heat transport system according to claim 8, characterized in that, The step of pulse activation within the current oscillation cycle based on the pulse heating parameters includes: Based on the pulse heating parameters, pulse activation is performed within the forward stroke of the current oscillation cycle, wherein the pulse heating parameters include heating current; During the reverse stroke within the current oscillation cycle, the heating current is reduced so that the average heating power during the reverse stroke is less than the average heating power during the forward stroke.

10. The control method for the magnetic fiber array phase-locked pulse heat transport system according to claim 8, characterized in that, The preset parameter determination mechanism includes determining the pulse heating parameters for pulse activation based on at least one of the preset target temperature rise threshold, fluid thermal diffusivity, heat capacity of conductive heating unit, cilia oscillation period, and duration of forward thrust work stroke.

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