Power-limited oscillation electrode system for enhancing heat exchange of cavity and control method

Abstract

The invention discloses a power-limited oscillation electrode system for enhancing cavity heat exchange and a control method, and belongs to the technical field of fluid. The first electrode and the second electrode are arranged on the left side and the right side in the cavity; the first actuator and the second actuator can swing transversely and are used for applying vibration with the amplitude being A and the frequency being f; a driver for applying an electrical bias; the controller is used for selecting {A, f, phi} according to a power constraint condition P = Pselect + Pact < = Pmax so as to improve a heat transfer index, and the electrode I and the electrode II are respectively mounted on an actuator I and an actuator II which can transversely swing. In this way, higher heat conduction efficiency per watt is achieved by jointly optimizing field power and mechanical driving; and hot spot positioning is realized through phase control motion and closed-loop self-adaption.

Description

Technical Field

[0001] This invention relates to the field of fluid technology, and more specifically to a power-limited oscillating electrode system and control method for enhancing heat transfer in cavities. Background Technology

[0002] The miniaturization and high power density of compact devices have led to increasing challenges related to localized hotspots and transient heat loads. Traditional solutions (such as steady-state fans, heat sinks, microchannels, and static electrode thermocouples) have significant limitations: firstly, their heat transfer efficiency per watt is limited, and they lack adaptability when the location of hotspots or the intensity of the load changes. Secondly, static electrode thermocouples rely on fixed electrodes and bias voltages, making it difficult to adjust the fluid structure according to real-time requirements. Therefore, there is an urgent need for a low-profile system that can reconfigure internal transport paths, accurately locate hotspot areas, and optimize heat transfer efficiency under the dual constraints of electric field power and mechanical drive power.

[0003] Based on this, the present invention designs a power-limited oscillating electrode system and control method for cavity heat transfer enhancement to solve the above problems. Summary of the Invention

[0004] In view of the above-mentioned shortcomings of the prior art, the present invention provides a power-limited oscillating electrode system and control method for enhancing cavity heat transfer.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A power-constrained oscillating electrode system for enhancing cavity heat transfer includes a chamber for containing fluid; electrodes one and two on the left and right sides inside the chamber; actuators one and two capable of laterally oscillating for applying vibrations with amplitude A and frequency f; a driver for applying an electrical bias voltage; and a device for applying a power constraint P=P elec +P act ≤P max Select {A, f, φ} to improve the heat transfer performance of the controller; where A represents the mechanical stroke amplitude, f represents the frequency, φ represents the phase offset between two or more moving electrodes, and P represents the total system power consumption, including electrical bias power P0. elec and mechanical drive power P ac P max This indicates the total power budget; Electrode 1 and Electrode 2 are respectively mounted on Actuator 1 and Actuator 2, which can swing laterally.

[0006] Furthermore, the chamber is any enclosure, gap, channel, or packaging area for a closed working fluid; the chamber has a characteristic length of 100-500µm.

[0007] Furthermore, the first electrode and the second electrode can be selected as strip electrodes, comb electrodes, or perforated plates.

[0008] Furthermore, the actuator one and actuator two are selected from piezoelectric stacks, voice coil motors, electrostatic comb drivers, or magnetostrictive elements.

[0009] Furthermore, actuator one and actuator two are selected as electrostatic comb drivers operating at 100-1000Hz.

[0010] Furthermore, it also includes one or more sensors for measuring temperature and / or electrical parameters.

[0011] Furthermore, electrodes one and two have the following characteristics: length L = 0.1-500 mm, electrode span 0.1-0.9 L, and thickness 10-2000 µm; actuators one and two have a conductivity of 0.005 L ≤ A ≤ 0.3 L and a frequency f = 0.1-2000 Hz; φ is within the range of [0, 2π] °; the fluid used is an electrolyte with a conductivity σ between 0.01 and 5 S / m; and the total power budget P... max The wattage ranges from 0.05 to 50 watts.

[0012] Furthermore, the controller forces P to execute elec ∈[α P max , β P max ] and P act =P max -P elec , where 0.3≤α<β≤0.9.

[0013] To better achieve the objectives of this invention, the present invention also provides a control method employing the aforementioned power-limited oscillating electrode system for cavity heat transfer enhancement, comprising the following steps: S100: Initialize A, f, φ, and P max Boundary parameters; S120: Mechanically vibrate at least one electrode with amplitude A and frequency f; apply an electrical bias voltage to the electrode; S140: Sensor measures thermal / electrical signals; S160: The controller calculates P=P based on the acquired signal. elec +P act And in P≤P max Under the constraints, update the electrode oscillation parameters (A, f, φ); S180: Select the optimal solution, which includes the optimal combination of parameters {A, f, φ}, and the corresponding maximized Nusselt index Nu or minimized peak temperature T of the wall region. peak； S200: Maintain optimal solution or track against interference.

[0014] Furthermore, the sensor collects the temperature, driving voltage, and operating current of the chamber and electrodes, and transmits the data to the controller. The controller transmits the optimal solution to the drive module, which generates the corresponding electrical bias signal. The actuator receives the drive signal and drives the electrodes to complete oscillating motion in the chamber, disturbing the fluid to enhance heat transfer. The temperature, driving voltage, and operating current of the chamber and electrodes are transmitted back to the controller through the feedback link, forming a closed loop.

[0015] Compared to existing technologies, the advantages of this invention are as follows: This invention achieves higher heat transfer efficiency per watt by jointly optimizing field power and mechanical drive; and achieves hotspot positioning through phase-controlled motion and closed-loop adaptive operation. The cavity of this invention is equipped with mechanical oscillation electrodes, achieving precise control by reshaping internal fluid transport. The controller can autonomously adjust the oscillation amplitude A, frequency ω, and relative phase φ, and can optionally be equipped with a bias waveform to achieve power constraints P≤P max Maximize the Nusselt index Nu or minimize the peak temperature T of the wall region. peak This method maximizes heat transfer performance based on the Nusselt heat transfer coefficient while effectively controlling temperature rise and strictly managing the total energy consumption budget, including electricity and drive power. It is applicable to aqueous electrolyte, polar dielectric, or engineering fluid environments in millimeter- to wafer-level chambers and micro-gap spaces. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0017] Figure 1 This is a schematic diagram of a fluid-filled chamber.

[0018] Figure 2 This is a control block diagram of the present invention.

[0019] Figure 3 The time sequence diagram shows the relationship between the electrode displacements of the first electrode (20) and the second electrode (22) and time, which is driven by a basic phase shift (phase shift φ≈π).

[0020] Figure 4 This is a flowchart of the processing of the present invention.

[0021] Figure 5 To replace the electrode geometry.

[0022] Figure 6The example curves showing the average Nusselt number of the wall versus the oscillation frequency at a fixed power output illustrate the peak performance within the tuning band.

[0023] Figure 7 This is a schematic diagram of the flow structure and hotspot location within the chamber. Electrical oscillations precisely match the cooling capacity with the heat generation region by reshaping vortex transport and boundary layer thickness. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 creative effort are within the scope of protection of the present invention.

[0025] Example 1: Please refer to the accompanying drawings in the instruction manual. Figure 1 A power-constrained oscillating electrode system for enhancing cavity heat transfer includes a chamber 10 for containing fluid 12; electrodes 20 and 22 on the left and right sides inside the chamber 10; laterally oscillating actuators 30a and 30b for applying vibrations with amplitude A and frequency f; a driver 32 for applying an electrical bias voltage; and a power constraint condition P=P elec +P act ≤P max Controller 50 selects {A, f, φ} to improve heat transfer performance. A represents the mechanical stroke amplitude (peak displacement), f represents the frequency, φ represents the phase offset between two or more moving electrodes, and P represents the total system power consumption, including electrical bias power P0. elec and mechanical drive power P ac P max This indicates the total power budget. Electrode 1 20 and Electrode 2 22 are respectively mounted on actuator 1 30a and actuator 2 30b, which can swing laterally. Figure 1 The representative internal streamlines and local hot spots are marked with dashed outlines (hot spots refer to areas with temperatures above the threshold or in the top 10%).

[0026] The chamber 10 is any enclosing structure, gap, channel, or packaging area for the closed working fluid 12. The chamber 10 has a characteristic length of 100-500µm. The materials for the chamber 10 and the flow channel can be selected from: polyetheretherketone (PEEK), polyphenylene sulfide (PPSU), glass, ceramic, or passivated metal.

[0027] The characteristic parameters of the fluid 12 include ρ (density), μ (viscosity), k (thermal conductivity), cp (specific heat capacity), and σ (electrical conductivity). The material of fluid 12 can be selected from: water / ethylene glycol solution (containing salt, concentration 0.01-5M), dielectric oil (concentration σ≈0), or polar solvent; nanoparticles with a volume fraction not exceeding 1% can be further added.

[0028] like Figure 5 As shown, electrodes 20 and 22 can be selected from structures such as strip electrodes (variant A), comb electrodes (variant B), or perforated plates (variant C). Each electrode is arranged within chamber 10 and driven by a phase difference. Electrodes 20 and 22 employ rounded edges (radius 5-200µm) to suppress field singularities; they also feature a microporous design (0.1-2 mm) to shape local jet morphology and reduce drag. Electrode materials can be selected from copper, aluminum, gold-plated stainless steel, indium tin oxide (ITO), or platinum.

[0029] The actuators 30a and 30b can be piezoelectric stacks (micrometer-millimeter stroke, operating frequency 1-500Hz), voice coil motors (operating frequency 1-100Hz), electrostatic comb drivers (MEMS, 10-1000Hz), or magnetostrictive elements. The motion trajectory can be linear, circular, elliptical, or racetrack-shaped.

[0030] Preferably, the actuator 30a and actuator 30b are electrostatic comb drivers operating at 100-1000Hz.

[0031] The electrical bias adopts a multi-mode design: a) DC bias with mechanical oscillation; b) DC level bias with synchronous AC component; c) pulse bias synchronized with motion; with multiple types of adaptive waveforms: sine wave, triangle wave or pulse width modulation (PWM) wave (10-90% duty cycle).

[0032] Preferably, it also includes one or more sensors 40 for measuring temperature (wall temperature, body temperature) and / or electrical parameters (voltage or current).

[0033] Sensor 40 can be selected from temperature sensors (such as micro resistance thermometers, thermistors, infrared sensors), voltage / current sensors, and can be equipped with flow agents (micro filaments, MEMS pressure sensors).

[0034] Typical dimensions and ranges (non-limiting): Electrode 1 20, Electrode 2 22: Length L = 0.1-500 mm, Electrode span 0.1-0.9L, Thickness 10-2000µm; Actuator 1 30a and Actuator 2 30b: 0.005L≤A≤0.3L (10µm-3 mm), f = 0.1-2000Hz (typically 1-100Hz); φ in the range [0, 2π], preferably out-of-phase 150°-210°; Fluid 12 uses an electrolyte with conductivity σ between 0.01 and 5 S / m (preferably 10 S / m); Total power budget P max The wattage ranges from 0.05 to 50 watts.

[0035] In the Businski approximation, ρcp(∂T / ∂t+u·∇T)=k∇ 2 T + qJ + qdev. Where ρ represents density, cp represents specific heat capacity, u represents the fluid velocity field, ∇T represents the temperature gradient, and k represents thermal conductivity. 2 T represents the thermal diffusivity term, qJ represents the Joule heat power density, and qdev represents the additional volumetric power (deformation energy term) generated by the mechanical oscillation of the electrodes. Mechanical vibration alters u through moving boundary conditions and EHD body forces. A practical objective is to achieve this in the wall region, where P=P elec +P act ≤P max Under the given conditions, maximize the Nusselt index Nu or minimize the peak temperature T of the wall region. peak .

[0036] Among them, controller 50 forces P to execute elec ∈[α P max , β P max ] and P act =P max -P elec , where 0.3≤α<β≤0.9.

[0037] The above-mentioned device can be used in the thermal management of electronic devices, battery modules, or power converters. It can be installed in the liquid cooling circuit of electronic packaging.

[0038] This invention achieves higher heat transfer efficiency per watt by jointly optimizing field power and mechanical drive; it achieves hotspot localization through phase-controlled motion and closed-loop adaptive operation (steps S140→S160→S180 (temperature detection → parameter update → target optimization)). The cavity of this invention is equipped with mechanical oscillation electrodes, achieving precise control by reshaping internal fluid transport. The controller can autonomously adjust the oscillation amplitude A, frequency ω, and relative phase φ, and can optionally be equipped with a bias waveform to achieve power constraints P≤P max Maximize the Nusselt index Nu or minimize the peak temperature T of the wall region. peakThis method maximizes heat transfer performance based on the Nusselt heat transfer coefficient while effectively controlling temperature rise and strictly managing the total energy consumption budget, including electricity and drive power. It is applicable to aqueous electrolyte, polar dielectric, or engineering fluid environments in millimeter- to wafer-level chambers and micro-gap spaces.

[0039] Example 2: Please refer to the accompanying drawings in the instruction manual. Figure 2 and Figure 4 The control method for the power-limited oscillating electrode system used for cavity heat transfer enhancement includes the following steps: S100: Initialize A, f, φ, and P max Boundary parameters; S120: Mechanically vibrate at least one electrode with amplitude A and frequency f; apply electrical bias voltage (DC / AC / mixed mode) to the electrode. S140: Sensor 40 measures thermal / electrical signals; Specifically, sensor 40 collects the temperature (T), driving voltage (V), and operating current (I) of chamber 10 and electrodes, and transmits the data to controller 50; S160: Controller 50 calculates P=P based on the acquired signal. elec +P act And in P≤P max Under constraints, update the electrode oscillation parameters (A, f, φ). For example, if Nu↓→increase A or f; if T peak ↑→ Decrease A, f, or optimize φ; S180: Select the optimal solution, which includes the optimal combination of parameters {A, f, φ}, and the corresponding maximized Nusselt index Nu or minimized peak temperature T of the wall region. peak； S200: Maintain optimal solution or track against interference.

[0040] The controller 50 transmits the optimal solution to the drive module 32, which generates a corresponding electrical bias signal. The actuator receives the drive signal and drives the electrode to complete an oscillating motion within the chamber 10, disturbing the fluid to enhance heat transfer. The thermal / electrical performance signals of the chamber 10 and the electrode are transmitted back to the controller 50 via a feedback link, forming a closed loop for continuous parameter optimization.

[0041] Experimental Example 1: (Millimeter-scale aqueous phase): 100×60×10 mm chamber 10, fluid 12, conductivity σ=0.5 S / m, two 50×30 mm copper rod electrodes (side length 100µm), piezoelectric stack; Pmax=3 W(P elec =1.8 W, P ac=1.2 W). A=0.5–1.5 mm, f=5–12 Hz, φ=π; optimal parameters A*=1.0 mm, f*≈8 Hz. Gain comparison with static electrode at equal power: Nu+35%, peak wall temperature -12 K ( Figure 6 ).

[0042] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power-constrained oscillating electrode system for enhancing cavity heat transfer, characterized in that, Includes a chamber (10) for containing fluid (12); electrode one (20) and electrode two (22) on the left and right sides inside the chamber (10); actuator one (30a) and actuator two (30b) that can swing laterally for applying vibration with amplitude A and frequency f; driver (32) for applying electrical bias voltage; and driver for applying power constraint P=P elec +P act ≤P max Select {A, f, φ} to improve the heat transfer performance of the controller (50); where A represents the mechanical stroke amplitude, f represents the frequency, φ represents the phase offset between two or more moving electrodes, and P represents the total power consumption of the system, including the electrical bias power P. elec and mechanical drive power P ac P max The total power budget is indicated; Electrode 1 (20) and Electrode 2 (22) are respectively mounted on actuator 1 (30a) and actuator 2 (30b) which can swing laterally.

2. The power-constrained oscillating electrode system for enhancing cavity heat transfer according to claim 1, characterized in that, The chamber (10) is any enclosing structure, gap, passage or packaging area of ​​a closed working fluid (12); the chamber (10) has a characteristic length of 100-500µm.

3. The power-constrained oscillating electrode system for enhancing cavity heat transfer according to claim 1, characterized in that, The first electrode (20) and the second electrode (22) are selected as strip electrodes, comb electrodes or perforated plates.

4. The power-constrained oscillating electrode system for enhancing cavity heat transfer according to claim 1, characterized in that, The actuator one (30a) and actuator two (30b) are selected from piezoelectric stacks, voice coil motors, electrostatic comb drivers or magnetostrictive elements.

5. The power-constrained oscillating electrode system for enhancing cavity heat transfer according to claim 1, characterized in that, The actuator one (30a) and actuator two (30b) are selected to operate as electrostatic comb drivers in the range of 100-1000 Hz.

6. The power-constrained oscillating electrode system for enhancing cavity heat transfer according to claim 5, characterized in that, It also includes one or more sensors (40) for measuring temperature and / or electrical parameters.

7. The power-constrained oscillating electrode system for enhancing cavity heat transfer according to claim 6, characterized in that, Electrode 1 (20), Electrode 2 (22): Length L = 0.1-500 mm, Electrode span 0.1-0.9 L, Thickness 10-2000 µm; Actuator 1 (30a) and Actuator 2 (30b): 0.005 L ≤ A ≤ 0.3 L, f = 0.1-2000 Hz; φ in the range [0, 2π] °; Fluid (12) uses an electrolyte with conductivity σ between 0.01 and 5 S / m; Total power budget P max The range is from 0.05 to 50 watts.

8. The power-constrained oscillating electrode system for enhancing cavity heat transfer according to claim 1, characterized in that, Controller (50) enforces P elec ∈[α P max , β P max ] and P act =P max -P elec , where 0.3≤α<β≤0.

9.

9. A control method for a power-constrained oscillating electrode system for cavity heat transfer enhancement as described in any one of claims 1 to 8, characterized in that, Includes the following steps: S100: Initialize A, f, φ, and P max Boundary parameters; S120: Mechanically vibrate at least one electrode with amplitude A and frequency f; apply an electrical bias voltage to the electrode; S140: Sensor (40) measures thermal / electrical signals; S160: The controller (50) calculates P=P based on the acquired signal. elec +P act And in P≤P max Under the constraints, update the electrode oscillation parameters (A, f, φ); S180: Select the optimal solution, which includes the optimal combination of parameters {A, f, φ}, and the corresponding maximized Nusselt index Nu or minimized peak temperature T of the wall region. peak； S200: Maintain optimal solution or anti-interference tracking.

10. The control method according to claim 9, characterized in that, The sensor (40) collects the temperature, driving voltage and operating current of the chamber (10) and electrodes, and transmits the data to the controller (50); the controller (50) transmits the optimal solution to the drive module (32), and the drive module (32) generates the corresponding electrical bias signal; The actuator receives the drive signal and drives the electrode to complete the oscillating motion in the chamber (10), disturbing the fluid to enhance heat transfer; the temperature of the chamber (10) and the electrode, the drive voltage and the operating current are transmitted back to the controller (50) through the feedback link to form a closed loop.

Images