A temperature precision control device based on bionic structure and multi-layer temperature control

Abstract

The present invention discloses a temperature precision control device based on a bionic structure and multi-layer temperature control, which relates to thermostat technology. In order to solve the problems of low thermal conductivity, weak anti-fluctuation ability and insufficient precision in the prior art, the present device comprises: a nested three-layer constant temperature structure (10), including an inner layer (11), a middle layer (12) and an outer layer (13), with inert gas filled between the layers to achieve step-by-step temperature control; a bionic fractal heat-conducting structure (20) arranged between the inner and middle layers; an electric heating plate (30) and an inverse Peltier (31) connected to the end of the heat-conducting structure and connected to the middle layer for active temperature control; and a sensor matrix (40) distributed in the inner layer for precise monitoring. The present invention combines a multi-layer structure, efficient bionic heat conduction and intelligent regulation to significantly improve temperature control precision, efficiency and response speed, and is suitable for precision instruments such as satellite atomic clocks.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature control, and in particular to a device for high-precision temperature control, specifically a temperature precision control device based on a bionic structure and multi-layer temperature control. Background Art

[0002] In many fields such as aerospace, precision instruments, and biomedicine, it is crucial to accurately and stably control the temperature of specific components or spaces. For example, in satellite navigation systems, atomic clocks, as core components, provide high-precision time references, and their frequency stability and accuracy are extremely sensitive to temperature fluctuations. Traditional temperature control devices, such as those that use simple homogeneous material patches or single metal columns for heat conduction, often have low thermal efficiency and poor temperature distribution uniformity. Using a single-cavity temperature control structure, its internal ability to resist ambient temperature fluctuations is limited. Although some studies have attempted to use random branch configurations to improve thermal conductivity, they usually face problems of complex processing and high costs.

[0003] Satellites and other space applications place higher demands on temperature control systems. Traditional satellite thermal control designs, including passive temperature control (such as multi-layer insulation coatings) and active temperature control (such as heater power regulation), often suffer from poor heat distribution, insufficient cooling capacity, and difficulty eliminating local hot spots when faced with complex thermal environments and high precision requirements. These issues limit the full performance of onboard precision payloads (such as atomic clocks).

[0004] Therefore, there is an urgent need for a temperature control device that can achieve high precision, high stability, high efficiency and uniform temperature distribution to meet the growing demand for precision temperature control. Summary of the Invention

[0005] The main purpose of the present invention is to overcome the shortcomings of the existing technology and provide a temperature precision control device based on bionic structure and multi-layer temperature control, which has the advantages of high temperature control accuracy, excellent thermal conductivity, good temperature uniformity, and fast response speed.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A temperature precision control device based on bionic structure and multi-layer temperature control. Its core feature is the combination of a multi-layer nested constant temperature structure, an efficient bionic fractal heat conduction structure, active heating / cooling elements and a precise temperature sensing feedback system.

[0008] The device includes:

[0009] Three-layer constant temperature structure (10): from the inside to the outside, it is the inner layer (11), the middle layer (12) and the outer layer (13). These three layers are nested in each other to form physical isolation and buffer. The inner layer (11) directly surrounds or accommodates the temperature-controlled components that need to be precisely temperature-controlled (such as atomic clocks). Preferably, the space between the layers and the interior of the inner layer (11) can be sealed and filled with inert gas (such as argon, nitrogen, etc.), the purpose of which is to use the low thermal conductivity of the inert gas to reduce the convection and heat transfer between the layers, further enhance the thermal insulation performance and the stability of the cavity environment. The three-layer structure functionally realizes step-by-step temperature control: the outer layer (13) is responsible for resisting the main temperature fluctuations of the external environment and achieving rough temperature control (coarse temperature control zone); the middle layer (12) performs more fine temperature adjustment (fine temperature control zone); and the inner layer (11) achieves the final precise temperature control (precision temperature control zone) in an extremely stable thermal environment.

[0010] Bionic heat-conducting structure (20): It is cleverly arranged between the inner layer (11) and the middle layer (12) to serve as an efficient heat transfer channel between the two. The design of this structure is inspired by the efficient transport network in nature, such as the leaf vein structure of plants, and is designed using fractal geometry principles. Specifically, it can be a multi-level branching structure, such as a four-level branching structure, including a main channel (21), a primary channel (22), a secondary channel (23), a tertiary channel (24) and a quaternary channel (25). The channel branches from the main trunk step by step until the end. The branching direction is designed to be perpendicular to the interlayer structure of the inner and middle layers to ensure that heat can be effectively transferred from one plane to another. More importantly, the size of the channel (especially the cross-sectional area) is optimized according to the improved Murray law. By analogizing heat conduction to fluid flow (as shown in Table 1), an optimization criterion applicable to heat conduction scenarios was derived: when the cross-sectional area ratio of adjacent channels (such as a parent channel to a child channel) reaches a specific value (for example, the theoretically derived 1.587:1), the thermal resistance of the entire heat conduction network is minimized, thereby achieving the highest heat conduction efficiency. This biomimetic optimization design enables rapid and low-loss heat transfer between the heating / cooling element and the inner layer.

[0011] Table 1. Analogy correspondence of basic physical quantities

[0012]

[0013] Active temperature control element: includes at least one electric heating plate (30) and at least one reverse Peltier (31) (also known as semiconductor cooling plate TEC). These elements are respectively connected to different end channels (such as the four-stage channel 25) of the bionic heat-conducting structure (20), and they all establish good thermal contact with the middle layer (12). When the electric heating plate (30) is energized, it generates Joule heat for heating the inner layer. When the reverse Peltier (31) is energized, it can actively pump heat from its cold end (the side close to the inner layer or the bionic structure) to its hot end (the side close to the middle layer or the outside), thereby achieving active cooling or heat dissipation of the inner layer. By coordinating the control of the heating plate and the reverse Peltier, the temperature of the inner layer can be precisely adjusted in both directions.

[0014] Sensor matrix (40): It is composed of a plurality of high-precision temperature sensors distributed at key positions of the inner layer (11) to form a sensor network. Their function is to monitor the temperature distribution of the inner layer (11) surface in real time and accurately, and to feed back the temperature data to the control system.

[0015] In addition, to further improve the overall performance, the outer surface of the outer layer (13) can be coated with a multi-layer reflective insulation material (MLI) to minimize the radiant heat exchange with the external environment. At the same time, a high-power electric heater and a corresponding temperature sensor can also be attached to the outer layer (13) for coarse temperature control of the outer layer. The heat dissipation is usually connected to the overall thermal management system of the satellite and other platforms.

[0016] The beneficial effects that the present invention can bring are as follows.

[0017] The control system receives real-time temperature data from the sensor matrix (40). When the inner layer temperature is detected to be lower than the set value, the control system instructs the electric heating plate (30) to work, and the heat is quickly transferred to the inner layer (11) through the efficient bionic heat-conducting structure (20). When the inner layer temperature is detected to be higher than the set value, the control system instructs the inverse Peltier (31) to work, and actively pumps out the excess heat of the inner layer (11) through the bionic heat-conducting structure (20). The three-layer constant temperature structure provides a strong thermal buffering capacity, gradually attenuating external interference. The bionic heat-conducting structure ensures the efficiency and uniformity of heat transfer. The sensor matrix provides accurate feedback. This multi-faceted design enables the device to achieve:

[0018] 1) Extremely high-precision temperature control: Through the coordination of precision layers, sensor matrices, and active adjustment elements, temperature stability control at the mK level or even higher precision is achieved.

[0019] 2) Efficient heat transfer: The bionic fractal structure significantly reduces thermal resistance, and heat transfer is fast and efficient whether it is heating or cooling.

[0020] 3) Excellent temperature uniformity: The optimized heat conduction path helps to form a uniform temperature field in the inner layer.

[0021] 4) Rapid response capability: Active heating and cooling are combined to respond quickly to temperature changes.

[0022] 5) Strong anti-interference capability: The multi-layer structure effectively isolates external environmental fluctuations.

[0023] Beneficial effect application examples:

[0024] This device is applied to the temperature control scenario of satellite atomic clocks. The inner layer (11) tightly wraps the atomic clock body, and the sensor matrix (40) monitors the temperature of the key parts of the atomic clock. The control system adjusts the electric heating plate (30) and the inverse Peltier (31) according to the feedback to accurately maintain the temperature of the atomic clock at the optimal working point (for example, 40.000℃). The temperature fluctuation range is extremely small (for example, ±0.01℃), which is far superior to traditional methods (such as Figure 8 、 Figure 9 This ensures the long-term frequency stability and accuracy of the atomic clock, thereby improving the performance of the entire satellite navigation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the overall structure of the device provided by an embodiment of the present invention.

[0026] Figure 2 A partial enlargement and relative position diagram of the bionic heat-conducting structure (20), the electric heating plate (30), the inverse Peltier (31) and the sensor matrix (40).

[0027] Figure 3 A schematic diagram of an exemplary configuration of a bionic heat-conducting structure (20) is shown.

[0028] Figure 4 It is a vertical view of the bionic heat-conducting structure (20), showing its connection relationship with the electric heating plate (30) and the inverse Peltier (31).

[0029] Figure 5 Schematic diagram of thermal simulation results of bionic heat-conducting structure, showing heat distribution.

[0030] Figure 6 This is the temperature gradient curve of the device of the present invention under specific working conditions (target 40°C, environment 35°C, working 180S).

[0031] Figure 7 This is the temperature gradient curve of the device of the present invention after reaching a stable state under specific working conditions.

[0032] Figure 8This is the temperature gradient curve after 180 seconds of operation under the same working conditions using the existing technology.

[0033] Figure 9 It is the temperature gradient curve after reaching a stable state under the same working conditions using the existing technology.

[0034] Markings in the figure: 10-three-layer constant temperature structure, 11-inner layer, 12-middle layer, 13-outer layer, 20-bionic heat conductive structure, 21-main channel, 22-primary channel, 23-secondary channel, 24-tertiary channel, 25-quaternary channel, 30-electric heating plate, 31-inverse Peltier, 40-sensor matrix. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are exemplary and are only used to explain the present invention and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] Example 1

[0037] Reference Figures 1 to 5 This embodiment provides a temperature precision control device based on bionic structure and multi-layer temperature control for satellite atomic clock temperature control.

[0038] The device comprises a three-layer constant temperature structure (10), a bionic heat-conducting structure (20), an electric heating plate (30), an inverse Peltier (31), and a sensor matrix (40).

[0039] The three-layer constant temperature structure (10) is composed of an inner layer (11), a middle layer (12) and an outer layer (13) nested in sequence. The material can be a metal or alloy with a low thermal expansion coefficient, such as Invar or titanium alloy. The inner layer (11) is designed to be cylindrical and tightly wraps the cylindrical atomic clock body. The gaps between the inner layer (11), the middle layer (12) and the outer layer (13) and the space around the atomic clock inside the inner layer (11) are sealed and filled with an inert gas with a low thermal conductivity coefficient, such as argon (Ar), after assembly. The pressure can be set to be slightly higher than the external ambient pressure to prevent leakage. The outer layer (13) constitutes a coarse temperature control zone, the middle layer (12) constitutes a fine temperature control zone, and the inner layer (11) constitutes a precision temperature control zone.

[0040] The bionic heat-conducting structure (20) is arranged between the inner layer (11) and the middle layer (12), and is made of a material with a high thermal conductivity coefficient, such as oxygen-free copper or aluminum alloy. The structure is designed to imitate the four-level fractal branching structure of plant veins, including a main channel (21), a primary channel (22), a secondary channel (23), a tertiary channel (24) and a quaternary channel (25). The channel starts from the trunk (main channel 21) and branches step by step at specific angles and proportions until the fourth channel (25) at the end. The branching direction is perpendicular to the interlayer structure of the inner and middle layers. According to the improved Murray law optimization design, the cross-sectional area ratio between adjacent channels (such as the main channel and the primary channel, the primary channel and the secondary channel, etc.) is set to 1.587:1 to minimize the overall thermal resistance.

[0041] A plurality of electric heating sheets (30) (e.g., thin film heaters) and a plurality of inverse Peltiers (31) (TEC modules) are installed uniformly or distributed as needed on the inner surface of the middle layer (12), and are well connected to the ends of the four-level channels (25) of the bionic heat-conducting structure (20) through heat-conducting interface materials.

[0042] The high-precision sensor matrix (40) is composed of a plurality of patch-type platinum resistance temperature sensors (RTDs) and is attached to the outer surface of the inner layer (11) for accurately monitoring the temperature of different areas of the inner layer.

[0043] The outer layer (13) is wrapped with multi-layer insulation material (MLI), and a coarse control heating plate with high power and a temperature sensor are attached to connect to the integrated thermal control system of the satellite.

[0044] During operation, the central controller accurately adjusts the heating power of the electric heater (30) and the cooling power (or the direction and magnitude of the working current) of the inverse Peltier (31) according to the feedback from the sensor matrix (40) through PID (proportional-integral-differential) or other advanced control algorithms, and stabilizes the temperature of the inner layer (11) at a preset value (e.g., 40.000±0.01°C), effectively suppressing the influence of internal and external thermal disturbances on the atomic clock, as shown in the thermal simulation results. Figure 6 and Figure 7 shown.

[0045] The design concept of the bionic heat conduction structure is: to imitate the fractal structure of plant leaf veins (the fractal dimension D can be 0.625), and to optimize the heat conduction metal path using the modified Murray's law (heat flow is analogous to fluid flow, and thermal resistance is equivalent to flow resistance); . is the radius of the main channel (21), For the The radius of the stage channel is the existing equation. Through the four-stage branch heat conduction structure, the terminal 4th stage channel ends at the electric heating plate (30) bonding plane and the inverse Peltier (31) heat dissipation plane, and is gradually transferred from the electric heating plate (30) through the terminal 4th stage channel to the main channel (21); the heat dissipation is gradually transferred from the main channel (21) to the terminal 4th stage channel.

[0046] For Table 1: Basic physical quantity analogy correspondence table, the relevant equations and laws are improved as follows:

[0047] Fluids (Poiseuille's law): , fluid flow Q l It is proportional to the fourth power of the radius and inversely proportional to the resistance. R is the pipe radius, p1-p2 is the pressure difference between the two ends of the pipe, η is the dynamic viscosity of the fluid, and l is the length of the pipe. Heat conduction (Fourier's law): , heat flow Q r It is proportional to the cross-sectional area A and thermal conductivity k, and inversely proportional to the length L. Among them, q x is the heat flux density, T1 is the temperature of the high temperature side, T2 is the temperature of the low temperature measurement, and the length L is the distance between these two points.

[0048] The derivation process of Murray's law of heat conduction is as follows:

[0049] 1) The goal is to find the distribution of cross-sectional area A to minimize thermal resistance loss.

[0050] 2) Under ideal conditions, the bifurcation is a symmetrical structure divided into two parts, the material texture is uniform (the thermal conductivity coefficient k is constant), convection and radiation are ignored, and heat conduction is considered.

[0051] 3) Variable definition:

[0052] Main channel: length L0, cross-sectional area A0, heat flow Q0; sub-channel: length L1, cross-sectional area A1, heat flow Q1 (the flow rate of each sub-channel is Q0 / 2).

[0053] Single channel thermal resistance:

[0054] ;

[0055] Among them, R d is the single channel radius, L d is the length of a single channel, A d is the single channel cross-sectional area.

[0056] 5) Minimize total thermal resistance:

[0057] If the mother channel is bifurcated into 4 levels of 16 sub-channels, the total thermal resistance needs to meet the following requirements:

[0058] ;

[0059] 6) Material Constraints: Assuming the total material volume is fixed [analogous to biological metabolic costs (fixed product weight)]:

[0060] ;

[0061] Solving the constrained optimization problem by the Lagrange multiplier method can finally yield:

[0062] ;

[0063] In the modified Murray's law representing the thermal conductivity version, the exponent is adjusted from 4 / 3 to 3 / 2 because thermal resistance is inversely proportional to cross-sectional area, while flow resistance is inversely proportional to the fourth power of radius.

[0064] It is found that when the cross-sectional area of ​​the mother channel is 1.587 times that of the child channel, the total thermal resistance is the smallest.

[0065] Example 2

[0066] This embodiment is basically the same as the first embodiment, except that:

[0067] Bionic heat-conducting structure (20): A three-level fractal branch structure is adopted, i.e., it only includes a main channel (21), a primary channel (22), and a secondary channel (23). The secondary channel (23) serves as the terminal channel connecting the electric heating plate (30) and the inverse Peltier (31). At the same time, the cross-sectional area ratio of adjacent channels is adjusted to 1.6:1 according to different boundary conditions or optimization goals (considering processing constraints). The material is an aluminum-based composite material with excellent thermal conductivity and light weight.

[0068] Filling Gas: Xenon (Xe) is used as the filling gas between layers and the inner layer. Xenon has a lower thermal conductivity than argon, so it can provide better passive thermal insulation, helping to further reduce heat transfer from the middle layer to the inner layer and improve the stability of the precision temperature control layer, but it is relatively expensive.

[0069] Sensor: The sensor matrix (40) uses a high-sensitivity thermistor array, which has higher resolution within a specific temperature range.

[0070] This embodiment is suitable for scenarios where extremely high thermal insulation performance is required and the complexity of the heat conduction structure can be slightly simplified.

[0071] Example 3

[0072] The main difference between this embodiment and embodiment 1 is:

[0073] Interlayer insulation method: The gaps between the inner layer (11), the middle layer (12), and the outer layer (13) as well as the inner space of the inner layer (11) are not filled with inert gas, but are insulated by vacuuming. or lower) can minimize gas convection and heat conduction, providing excellent thermal insulation performance. This requires the sealing structure between each layer to be extremely airtight, and it may be necessary to maintain a vacuum level for a long time in orbit.

[0074] Bionic thermal conductive structure material: Considering the outgassing characteristics of materials in a vacuum environment, the bionic thermal conductive structure (20) uses a high thermal conductivity material with a low outgassing rate, such as specially treated oxygen-free copper or thermal conductive graphite material. The structure can still use a four-level branch with a cross-sectional area ratio of 1.587:1.

[0075] Sensor type: The sensor matrix (40) uses temperature sensors suitable for vacuum environments, such as thin film platinum resistors or specially packaged thermocouples.

[0076] Applications: The device of this embodiment can be used for temperature control of other precision optical or electronic devices that require extremely high temperature stability and cleanliness, such as the pump source of a high-performance laser or an infrared focal plane array on a space probe.

[0077] This embodiment demonstrates another feasible solution for thermal insulation method and material selection, and is particularly suitable for applications in vacuum environments or where gas insulation is a concern.

[0078] Example 4

[0079] This embodiment is simplified based on the first embodiment, and the main differences are:

[0080] Active temperature control element: Only the electric heating plate (30) is installed in the middle layer (12), and no inverse Peltier (31) is installed. This means that the device mainly relies on heating for active temperature control, while cooling relies on passive heat dissipation to the external environment through the bionic structure (20), the middle layer (12), the outer layer (13) and the satellite platform cooling system.

[0081] Applicable Scenarios: This simplified solution is suitable for applications where the operating environment temperature is always below the target control temperature and the heat dissipation requirements are not high. Alternatively, it can serve as a low-cost, low-complexity alternative when a certain temperature overshoot and a slower cooling rate are acceptable.

[0082] This embodiment shows that, according to the actual heat load and environmental conditions, the configuration of the active temperature control element can be flexibly adjusted to meet different performance and cost requirements.

[0083] The core concepts and technical solutions of the present invention are described in detail above through several specific embodiments. These embodiments demonstrate the flexibility and scalability of the present invention in terms of structural hierarchy, material selection, thermal insulation method, active component configuration, and application objects, all of which fall within the scope of protection claimed by the present invention. For those skilled in the art, various modifications, combinations, or equivalent substitutions can be made to these embodiments without departing from the spirit and principles of the present invention, and these should all be considered as the scope of protection of the present invention.

Claims

1. A temperature precision control device based on bionic structure and multi-layer temperature control, characterized in that: include: A three-layer constant temperature structure (10) comprising an inner layer (11), a middle layer (12), and an outer layer (13) nested in sequence, wherein the inner layer (11) is used to accommodate or fix a component to be temperature-controlled; A bionic heat-conducting structure (20) is provided between the inner layer (11) and the middle layer (12), wherein the bionic heat-conducting structure (20) is a multi-level branching structure, the branching direction of which is perpendicular to the interlayer structure of the inner layer (11) and the middle layer (12), and has a plurality of terminal channels; At least one electric heating plate (30) and at least one inverse Peltier (31), respectively connected to different end channels of the bionic heat-conducting structure (20) and in thermal contact with the middle layer (12); A sensor matrix (40) is distributed on the inner layer (11) and is used to monitor the temperature distribution of the inner layer (11). The outer layer (13) constitutes a coarse temperature control zone, the middle layer (12) constitutes a fine temperature control zone, and the inner layer (11) constitutes a precise temperature control zone, thereby achieving step-by-step temperature control. The sensor matrix (40) is connected to a control system, and the control system adjusts the heating power of the electric heating plate (30) and the working state of the inverse Peltier (31) according to the temperature information monitored by the sensor matrix (40) to maintain the preset temperature of the inner layer (11).

2. The device according to claim 1, characterized in that The spaces between the inner layer (11), the middle layer (12) and the outer layer (13) as well as the interior of the inner layer (11) are sealed and filled with an inert gas.

3. The device according to claim 1, characterized in that The bionic heat-conducting structure (20) is a fractal structure that imitates the veins of plant leaves.

4. The device according to claim 3, characterized in that The bionic heat-conducting structure (20) is a four-level branch heat-conducting structure, comprising a main channel (21), a primary channel (22), a secondary channel (23), a tertiary channel (24), and a fourth channel (25) that are connected in sequence, and the fourth channel (25) is the terminal channel.

5. The device according to claim 4, characterized in that The cross-sectional area ratio between channels at adjacent branch levels in the bionic heat-conducting structure (20) is set to an optimized value that minimizes the total thermal resistance.

6. The device according to claim 5, characterized in that The cross-sectional area ratio between the channels of adjacent branch levels is 1.587:

1.

7. The device according to claim 1, characterized in that The outer surface of the outer layer (13) is covered with multiple layers of reflective heat insulation material, and an electric heater for coarse temperature control and a corresponding temperature sensor are attached thereto.

8. The device according to claim 1, characterized in that The component to be temperature-controlled is a satellite atomic clock.

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