A method for improving the temperature uniformity of a PCR well plate and a PCR well plate

Abstract

The present invention discloses a method for improving the temperature uniformity of a PCR well plate and a PCR well plate, which relate to the field of PCR well plates. The method determines the relationship between the unit heat density and the thickness of the well plate edge material through a calculation equation of unit heat and unit heat density, and analyzes the influence of the thickness of the well plate edge material on the second type of boundary conditions based on this relationship; according to the analysis results of the correlation between the unit heat density and the thickness of the well plate edge material and its influence on the second type of boundary conditions, the thickness of the well plate edge material is designed and set, so that a temperature zone is formed at the well plate edge during the heating and cooling processes; that is, the present invention forms a temperature ring by introducing a thickness change of the structure in the well plate edge area, and this temperature ring is slightly higher than the temperature of the well group when heating and slightly lower than the temperature of the well group when cooling. This design effectively reduces the edge effect, makes the temperature of the well plate edge area closer to the central area, thereby improving the uniformity of the overall temperature distribution.

Description

Technical Field

[0001] The present invention relates to the field of PCR well plates, and in particular to a method for improving the temperature uniformity of a PCR well plate and a PCR well plate. Background Art

[0002] Real-time fluorescence quantitative polymerase chain reaction (PCR) technology has become a key tool in molecular biology and medical research and clinical applications due to its real-time nature, sensitivity, and specificity. In well-plate PCR, temperature uniformity between wells significantly impacts the instrument's amplification performance. Especially for instruments with a melting curve function, the temperature gradient typically has a step size of 0.15°C, and inter-well temperature consistency must be within 0.1°C to ensure accurate melting peak analysis. Therefore, improving temperature uniformity is a key research priority for PCR equipment.

[0003] The temperature uniformity problem of well-plate PCR is a key factor affecting the accuracy and repeatability of experimental results. In well-plate PCR, temperature consistency between different wells is crucial, because large temperature differences between wells will lead to inconsistent amplification efficiency, thus affecting the experimental results. In addition, the temperature at the edge of the well plate is usually lower than that in the center area. This phenomenon is called the "edge effect", which further aggravates the uneven temperature distribution between wells. For instruments that collect fluorescence at the top, the Peltier can cover the entire heating area, so the temperature consistency is better, but the edge effect still exists. For instruments that collect fluorescence at the bottom, since the Peltier cannot be placed at the bottom of the well, the heat source can only be arranged on both sides or around the well, resulting in uneven heat source itself, poor heat conduction consistency, and more obvious edge effect.

[0004] Traditional approaches to addressing temperature uniformity in well-plate PCR systems often involve adding auxiliary heating devices, such as heating wires or heating films, to the bottom edge of the well plate to form the primary heating compensation mechanism, while the central heating and cooling structure still relies on Peltier technology as the primary temperature controller. Patent CN_101974421_A proposes a method for calculating compensation power, using empirically derived values ​​to construct a linear equation to calculate the compensation power. However, this method only addresses temperature non-uniformity at a specific point and fails to consider the heat capacity and temperature characteristics of the primary control temperature controller. Furthermore, during the cooling process, compensatory heating can exacerbate temperature drift in the heat dissipation system, increasing the control system's instability parameters. Another approach is to improve temperature uniformity by increasing the cooling area. However, while effective, this approach wastes space and increases power consumption, making it uneconomical. For example, the rejected patent CN_102174386_A employed this approach. Furthermore, using water as a heat dissipation medium can improve temperature uniformity by changing the heat conduction density load, but this compromises the heating rate due to water's high heat capacity. In summary, although these traditional methods have improved temperature uniformity to a certain extent, they each have limitations and fail to fully meet the requirements of rapid temperature change and efficient uniformity. Summary of the Invention

[0005] In order to solve the problem of how to improve temperature uniformity without reducing the heating and cooling speed, the present invention proposes a method for improving the temperature uniformity of a PCR well plate, comprising:

[0006] Construct the heat conduction differential equation through Fourier's heat conduction law;

[0007] The first type of boundary condition is set based on the fixed temperature at the edge of the orifice plate; the second type of boundary condition is set based on the heat density at the edge of the orifice plate; and the third type of boundary condition is set based on the convective heat transfer process between the edge of the orifice plate and the surrounding fluid.

[0008] The heat conduction differential equation is defined by the above three types of boundary conditions;

[0009] Based on the thermal conductivity of the orifice plate edge material, the orifice plate cross-sectional area perpendicular to the heat flow direction, and the temperature gradient, and combined with the heat conduction differential equation, the calculation equations for unit heat and unit heat density are constructed; the temperature gradient represents the rate of change of temperature along the heat flow direction; the unit heat represents the amount of heat passing through a preset cross-sectional area per unit time; and the unit heat density represents the amount of heat passing through a unit area per unit time;

[0010] The relationship between unit heat density and the thickness of the orifice plate edge material is determined by the calculation equation of unit heat and unit heat density, and based on this relationship, the influence of the orifice plate edge material thickness on the second type of boundary conditions is analyzed;

[0011] Based on the analysis results of the correlation between unit heat density and the thickness of the orifice plate edge material and its influence on the second type of boundary conditions, the thickness of the orifice plate edge material is designed and set so that a temperature zone is formed at the edge of the orifice plate during the heating and cooling process.

[0012] Furthermore, the heat conduction differential equation is constructed through Fourier's heat conduction law, which specifically includes:

[0013] The first formula is based on the fact that the heat conduction power per unit volume is equal to the heat source power per unit volume in steady-state heat transfer:

[0014] Where Q represents the heat source power per unit volume, that is, the total heat passing through the preset cross-sectional area A per unit time; represents the heat flux vector; represents the divergence operation;

[0015] The second formula is set based on Fourier's law of heat conduction:

[0016] Where T is the temperature field, are the unit direction vectors in the x, y, and z directions respectively, k x ,k y ,k z are the thermal conductivity of the orifice plate edge material along the x, y, and z directions respectively;

[0017] Substituting the second formula into the first formula, we get the third formula:

[0018]

[0019] By expanding the third formula in the rectangular coordinate system, the heat conduction differential equation is obtained:

[0020]

[0021] Furthermore, the first type of boundary condition is used to set the temperature of the orifice plate edge, and its formula is: T 边缘 =T1; where T 边缘 Indicates the temperature on the edge of the orifice plate, and T1 indicates the preset fixed temperature of the orifice plate edge;

[0022] The second type of boundary condition is used to specify the heat flux per unit area at the edge of the orifice plate, and its formula is:

[0023] Where, l x 、l y 、l z are the three components of the unit external normal vector on the edge of the orifice plate, indicating the direction of the orifice plate edge; q represents the unit heat density, that is, the amount of heat passing through a unit area per unit time;

[0024] The third type of boundary condition is used to limit the heat exchange between the edge of the orifice plate and the surrounding fluid, and its formula is:

[0025] Where, T ∞ express

[0026] The free stream temperature of the mainstream field at the edge of the orifice plate, T 表面 represents the temperature of the edge surface of the orifice plate, and h represents the convection heat transfer coefficient.

[0027] Furthermore, the calculation equation of the unit heat is: Where A represents the cross-sectional area of ​​the orifice plate perpendicular to the direction of heat flow, Q represents the total heat passing through the preset cross-sectional area A per unit time, and λ represents the thermal conductivity of the orifice plate edge material. It represents the temperature gradient, that is, the rate of change of temperature along the direction of heat flow;

[0028] The calculation equation of the unit heat density is: In the formula, q represents the unit heat density, that is, the amount of heat passing through a unit area per unit time.

[0029] Furthermore, the relationship between the unit heat density and the thickness of the orifice plate edge material is determined by the calculation equation of the unit heat and the unit heat density, specifically:

[0030] A thickness modulation heat conduction model is constructed to reflect the effect of the thickness change of the orifice plate edge material on heat conduction. The x-axis coordinate of the thickness modulation heat conduction model is the thickness position of the orifice plate edge material, and the y-axis coordinate is the temperature T.

[0031] The thermal conductivity of the orifice edge material does not change with the change of the x-axis coordinate, and the total heat passing through the preset cross-sectional area A per unit time does not change with the x-axis coordinate, and Integrate to get the integral formula: Where x1 represents the starting position of the thickness of the material at the edge of the orifice plate, x2 represents the ending position of the thickness of the material at the edge of the orifice plate; T1 and T2 represent the temperatures at the starting position and the ending position respectively;

[0032] The relationship between unit heat density and the thickness of the orifice plate edge material is obtained through the integral formula: In the formula, δ = x2-x1; in the formula, δ represents the thickness of the orifice plate edge material.

[0033] The embodiment of the present invention further provides a PCR well plate, comprising:

[0034] An orifice plate body, wherein the orifice plate body is provided with an accommodating hole group, and the accommodating hole group includes a plurality of accommodating holes;

[0035] The orifice plate body is provided with first edge plates on both sides along the length direction of the accommodating hole group, and the orifice plate body is provided with second edge plates and third edge plates on both ends along the length direction of the accommodating hole group; the thickness of the second edge plates and the third edge plates is less than that of the first edge plate;

[0036] The thickness ratio of the first edge plate, the second edge plate and the third edge plate is set by a method for improving the temperature uniformity of a PCR well plate as described in any one of claims 1 to 5.

[0037] Furthermore, when the thickness ratio of the first edge plate, the second edge plate and the third edge plate is set to 3:2:1, the heat flow direction is toward the side where the third edge plate is located;

[0038] When the thickness ratio of the first edge plate, the second edge plate and the third edge plate is set to 3:1:2, the heat flow direction is toward the side where the second edge plate is located.

[0039] Furthermore, the thickness of the second edge plate and the third edge plate are both greater than a preset threshold;

[0040] When the set thickness ratio does not satisfy the condition that the thickness of the second edge plate and the third edge plate are both greater than the preset threshold, the thickness relationship of the first edge plate, the second edge plate and the third edge plate is re-set based on the heat flow direction.

[0041] Furthermore, the thickness relationship of the first edge plate, the second edge plate, and the third edge plate is set based on the heat flow direction, specifically including:

[0042] When setting the heat flow direction to the side where the second edge plate is located, set:

[0043] Preset threshold < thickness of the second edge plate < thickness of the third edge plate < thickness of the first edge plate;

[0044] When setting the heat flow direction to the side where the third edge plate is located, set:

[0045] The preset threshold value < the thickness of the third edge plate < the thickness of the second edge plate < the thickness of the first edge plate.

[0046] Furthermore, the accommodating hole group includes a plurality of rows of accommodating holes, and Peltiers are provided on both sides of each row of accommodating holes;

[0047] Two ends of the Peltier extend from two ends of a corresponding row of accommodating holes respectively.

[0048] Compared with the prior art, the present invention has at least the following beneficial effects:

[0049] (1) The present invention determines the relationship between unit heat density and the thickness of the orifice plate edge material through the calculation equation of unit heat and unit heat density, and analyzes the influence of the thickness of the orifice plate edge material on the second type of boundary conditions based on this relationship; according to the correlation between unit heat density and the thickness of the orifice plate edge material and the analysis results of its influence on the second type of boundary conditions, the thickness of the orifice plate edge material is designed and set so that a temperature zone is formed at the edge of the orifice plate during the heating and cooling process; that is, the present invention forms a temperature ring by introducing a thickness change of the structure in the edge area of ​​the orifice plate. This temperature ring is slightly higher than the temperature of the accommodating hole group when heating up and slightly lower than the temperature of the accommodating hole group when cooling down. This design effectively reduces the edge effect and makes the temperature of the edge area of ​​the orifice plate closer to the central area, thereby improving the uniformity of the overall temperature distribution;

[0050] (2) The present invention does not require an independently installed auxiliary heating unit, and only requires the thickness of the structure to be changed at the edge of the orifice plate. This design is simple and easy to implement, reducing the complexity and manufacturing cost of the equipment;

[0051] (3) The present invention improves temperature uniformity while maintaining rapid temperature ramping. This method ensures temperature consistency and stability during rapid temperature ramping, meeting the requirements of modern qPCR technology for efficient and rapid temperature ramping.

[0052] (4) Since no additional auxiliary heating unit is required, the present invention reduces unnecessary energy consumption while improving temperature uniformity. Compared with traditional methods, such as increasing the cooling area or using high-heat-capacity water as a heat dissipation medium, the present invention reduces overall energy consumption while ensuring performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 A flow chart of a method for improving temperature uniformity of a PCR well plate;

[0054] Figure 2 This is the thickness modulation heat conduction model diagram;

[0055] Figure 3 Schematic diagram of the PCR plate structure;

[0056] Figure 4 This is a schematic diagram of the planar structure of a PCR well plate.

[0057] 1. First edge plate; 2. Second edge plate; 3. Third edge plate; 10. Accommodating hole group. DETAILED DESCRIPTION

[0058] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0059] Example 1

[0060] In order to ensure the consistency and stability of the temperature between wells during the rapid temperature change process and meet the requirements of modern PCR technology for efficient and rapid temperature change, such as Figure 1 As shown, an embodiment of the present invention provides a method for improving the temperature uniformity of a PCR well plate, comprising:

[0061] Construct the heat conduction differential equation through Fourier's heat conduction law;

[0062] The heat conduction differential equation is constructed through Fourier's heat conduction law, including:

[0063] The first formula is based on the fact that the heat conduction power per unit volume is equal to the heat source power per unit volume in steady-state heat transfer:

[0064] Where Q represents the heat source power per unit volume, that is, the total heat passing through the preset cross-sectional area A per unit time; represents the heat flux vector; represents the divergence operation;

[0065] The second formula is set based on Fourier's law of heat conduction:

[0066] Where T is the temperature field (the temperature field T describes the temperature at any point (x, y, z) inside the object), are the unit direction vectors in the x, y, and z directions respectively, k x ,k y ,k z are the thermal conductivity of the orifice plate edge material along the x, y, and z directions respectively;

[0067] Substituting the second formula into the first formula, we get the third formula:

[0068]

[0069] By expanding the third formula in the rectangular coordinate system, the heat conduction differential equation is obtained:

[0070]

[0071] The first type of boundary condition is set based on the fixed temperature at the edge of the orifice plate; the second type of boundary condition is set based on the heat density at the edge of the orifice plate; and the third type of boundary condition is set based on the convective heat transfer process between the edge of the orifice plate and the surrounding fluid.

[0072] The first type of boundary condition is used to set the temperature of the orifice plate edge, and its formula is: T 边缘 =T1; where T 边缘Indicates the temperature on the edge of the orifice plate, and T1 indicates the preset fixed temperature of the orifice plate edge;

[0073] The second type of boundary condition is used to specify the heat flux per unit area at the edge of the orifice plate, and its formula is:

[0074] Where, l x 、l y 、l z are the three components of the unit external normal vector on the edge of the orifice plate, indicating the direction of the orifice plate edge; q represents the unit heat density, that is, the amount of heat passing through a unit area per unit time;

[0075] The third type of boundary condition is used to limit the heat exchange between the edge of the orifice plate and the surrounding fluid, and its formula is:

[0076] Where, T ∞ express

[0077] The free stream temperature of the mainstream field at the edge of the orifice plate, T 表面 represents the temperature of the edge surface of the orifice plate, and h represents the convection heat transfer coefficient.

[0078] The heat conduction differential equation is defined by the above three types of boundary conditions;

[0079] Based on the thermal conductivity of the orifice plate edge material, the orifice plate cross-sectional area perpendicular to the heat flow direction, and the temperature gradient, and combined with the heat conduction differential equation, the calculation equations for unit heat and unit heat density are constructed; the temperature gradient represents the rate of change of temperature along the heat flow direction; the unit heat represents the amount of heat passing through a preset cross-sectional area per unit time; and the unit heat density represents the amount of heat passing through a unit area per unit time;

[0080] Since Fourier's law is the basic law of heat conduction, it states that the amount of heat per unit time is proportional to the temperature gradient and the cross-sectional area perpendicular to the direction of heat flow, therefore:

[0081] The calculation equation of the unit heat is: Where A represents the cross-sectional area of ​​the orifice plate perpendicular to the direction of heat flow, Q represents the total heat passing through the preset cross-sectional area A per unit time, and λ represents the thermal conductivity of the orifice plate edge material. It represents the temperature gradient, that is, the rate of change of temperature along the direction of heat flow;

[0082] The physical meaning of the unit heat calculation equation is that the total heat Q passing through the orifice cross-sectional area A is proportional to the orifice cross-sectional area, the thermal conductivity of the material, and the temperature gradient. The negative sign indicates that the direction of heat flow is from high temperature to low temperature, that is, the direction of heat flow is opposite to the direction of temperature increase.

[0083] The calculation equation of the unit heat density is: Here, q represents the unit heat density, or the amount of heat passing through a unit area per unit time. The negative sign indicates that the direction of heat flow is opposite to the direction of the temperature gradient.

[0084] The physical meaning of the equation for calculating unit heat density is that the amount of heat q passing through a unit area is proportional to the thermal conductivity of the material and the temperature gradient. Similarly, the negative sign indicates that the heat flow is from high temperature to low temperature.

[0085] The relationship between unit heat density and the thickness of the orifice plate edge material is determined by the calculation equation of unit heat and unit heat density, and based on this relationship, the influence of the orifice plate edge material thickness on the second type of boundary conditions is analyzed;

[0086] The relationship between the unit heat density and the thickness of the orifice plate edge material is determined by the calculation equation of unit heat and unit heat density, specifically:

[0087] Build as Figure 2 The thickness modulation heat conduction model shown is used to reflect the effect of the thickness change of the orifice plate edge material on heat conduction. The x-axis coordinate of the thickness modulation heat conduction model is the thickness position of the orifice plate edge material, and the y-axis coordinate is the temperature T.

[0088] The thermal conductivity λ of the orifice edge material does not change with the change of the x-axis coordinate, and the total heat Q passing through the preset cross-sectional area A per unit time does not change with the x-axis coordinate, and Integrate to get the integral formula: Where x1 represents the starting position of the thickness of the material at the edge of the orifice plate, and x2 represents the ending position of the thickness of the material at the edge of the orifice plate; T1 and T2 represent the temperatures at the starting position and the ending position, respectively (which are known fixed values);

[0089] The relationship between unit heat density and the thickness of the orifice plate edge material is obtained through the integral formula: In the formula, δ = x2-x1; in the formula, δ represents the thickness of the orifice plate edge material.

[0090] Figure 2 middle:

[0091] The red arrow indicates the direction of heat flow, and the isothermal surface is perpendicular to the direction of heat flow;

[0092] Q x With Q x+dx : represent the unit heat at the thickness position x and x+dx, respectively, reflecting the distribution of heat in the material;

[0093] Δx represents a small increment in space and is used to describe the temperature gradient during heat conduction;

[0094] The temperature difference between T1 and T2 drives the conduction of heat. Heat is transferred from the high temperature area (T1) to the low temperature area (T2).

[0095] In this embodiment, the integral formula shows that by reducing the thickness of the metal structure, the thermal conductivity coefficient and the thickness ratio λ / δ can be increased, resulting in an increase in the unit heat density q. This increase in q is not directly caused by the electrical power, but is caused by a change in the heat conduction path. Specifically, when the metal thickness in the edge area of ​​the orifice plate is reduced, the heat conduction load density in this area increases, so that during the temperature rise process, these thin areas will form a higher temperature zone than the thicker areas. This temperature zone can prevent the internal temperature from being transferred to the edge, thereby improving the temperature uniformity of the internal area.

[0096] During the cooling process, these thin areas form a cold ring, and the heat in the internal area will be balanced toward the cold ring, avoiding the gradient cooling effect caused by the heat dissipation direction at the bottom. Although the increase in q will cause the temperature to rise, the amount of increase will be limited by the distribution of the entire temperature field, ensuring that the temperature change is within a controllable range. This design utilizes reverse thinking and does not change the thermal power density, but instead changes the temperature field by changing the mass distribution of the metal. This method not only simplifies the structural design, but also improves the uniformity and efficiency of temperature control, avoiding the complexity and instability brought about by adding additional heat sources in traditional methods. In this way, the temperature uniformity problem in well-plate qPCR can be effectively solved without adding additional heat sources.

[0097] Based on the analysis results of the correlation between unit heat density and the thickness of the orifice plate edge material and its influence on the second type of boundary conditions, the thickness of the orifice plate edge material is designed and set so that a temperature zone is formed at the edge of the orifice plate during the heating and cooling process.

[0098] In this embodiment, the analysis result of the influence of the second type of boundary conditions is expressed by the following formula:

[0099]

[0100] In this embodiment, the edge of the orifice plate refers to the area surrounding the orifice group.

[0101] Existing patents typically address the problem of temperature uniformity by adding heat sources, but this approach suffers from the instability of thermal convection and needs to be limited. However, there are currently no known patents that improve temperature uniformity by changing heat conduction. Assuming the structure is made of metal of uniform mass, changing the thermal power density can cause changes in the thermal conduction density, thereby inducing changes in the boundary and temperature field. Using reverse thinking, the present invention does not change the thermal power density, but instead changes the mass distribution of the metal, which can also produce changes in the temperature field. Specifically, by thinning the metal structure in the edge areas of the orifice plate, the heat conduction load density in these areas is higher, thereby forming a temperature zone that is higher than the thicker areas when the temperature rises, preventing the internal temperature from being transferred to the edges and improving the temperature uniformity of the internal area. When the temperature is cooled, these thin areas form a cold ring, and the heat in the internal area will be balanced towards the cold ring, avoiding the gradient cooling effect caused by the heat dissipation direction at the bottom. This design not only simplifies the structure but also improves the uniformity and efficiency of temperature control.

[0102] Example 2

[0103] like Figure 3 and Figure 4 As shown, the embodiment of the present invention further provides a PCR well plate, comprising:

[0104] An orifice plate body, wherein the orifice plate body is provided with an accommodating hole group 10, and the accommodating hole group 10 includes a plurality of accommodating holes;

[0105] The orifice plate body is provided with a first edge plate 1 on both sides along the length direction of the accommodating hole group 10, and a second edge plate 2 and a third edge plate 3 are provided on both ends along the length direction of the accommodating hole group 10; the thickness of the second edge plate 2 and the third edge plate 3 are both smaller than the first edge plate 1;

[0106] In this embodiment, a heat cover that matches the size of the orifice plate body is also provided on the orifice plate body.

[0107] The thickness ratio of the first edge plate 1 , the second edge plate 2 and the third edge plate 3 is set by a method for improving the temperature uniformity of a PCR well plate according to any one of claims 1 to 5.

[0108] When the thickness ratio of the first edge plate 1, the second edge plate 2 and the third edge plate 3 is set to 3:2:1, the heat flow direction is toward the side where the third edge plate 3 is located;

[0109] When the thickness ratio of the first edge plate 1 , the second edge plate 2 and the third edge plate 3 is set to 3:1:2, the heat flow direction is toward the side where the second edge plate 2 is located.

[0110] In this embodiment, Figure 4As shown, the area framed by green lines indicates where the Peltier is placed, the area framed by red lines indicates the generated temperature zone, and the arrows in the figure indicate the direction of heat flow.

[0111] In this embodiment, the thickness ratio of the first edge plate 1 , the second edge plate 2 , and the third edge plate 3 may also be set to 3:1:1 or 3:2:2.

[0112] The thickness of both the second and third edge plates 2 and 3 is greater than a preset threshold. This limitation is intended to prevent excessive thinning from affecting the strength of the orifice plate base and to prevent thermal deformation and Peltier burnout due to excessive thinness. Furthermore, excessively thin edge plates can cause significant temperature differences during heating and cooling, leading to uneven heating and cooling within the Peltier and shortening its service life.

[0113] When the set thickness ratio does not satisfy the condition that the thickness of the second edge plate 2 and the third edge plate 3 are both greater than the preset threshold, the thickness relationship of the first edge plate 1, the second edge plate 2 and the third edge plate 3 is re-set based on the heat flow direction.

[0114] The thickness relationship between the first edge plate 1, the second edge plate 2, and the third edge plate 3 is set based on the heat flow direction, specifically including:

[0115] When the heat flow direction is set to the side where the second edge plate 2 is located, set:

[0116] Preset threshold < thickness of second edge plate 2 < thickness of third edge plate 3 < thickness of first edge plate 1;

[0117] When the heat flow direction is set to the side where the third edge plate 3 is located, set:

[0118] The preset threshold value is less than the thickness of the third edge plate 3 and less than the thickness of the second edge plate 2 and less than the thickness of the first edge plate 1 .

[0119] The receiving hole group 10 includes multiple rows of receiving holes, and Peltiers are provided on both sides of each row of receiving holes;

[0120] Two ends of the Peltier extend from two ends of a corresponding row of accommodating holes respectively.

[0121] like Figure 4 As shown, in this embodiment, to offset the gradient effect, the Peltier is extended nearly the length of one receiving hole, i.e., a wider Peltier is arranged in the direction of heat flow. This design creates a compensation temperature band at both ends of the receiving hole group 10, significantly improving the temperature consistency between the holes.

[0122] The present invention utilizes a portion of the Peltier's area as a power element for edge compensation, but does not design additional independent compensating heating channels, nor does it significantly expand the heating area. By varying the thickness of the microstructure of the heating block (i.e., the area of ​​the orifice plate covered by the Peltier surrounding the hole group), variations in the heat conduction density load are generated. Specifically, this is achieved by thinning the area of ​​the orifice plate covered by the Peltier surrounding the hole group. Because the heat conduction load density is higher in the thin areas where the heat source is located, this area heats up and down more quickly. During heating, these thin areas form a higher temperature band / ring than the thicker areas. This temperature band / ring prevents internal temperature from transferring to the edges, thereby improving temperature uniformity within the internal area. During cooling, this temperature ring becomes a cold ring, and the heat within the internal area balances toward the cold ring, avoiding the gradient cooling effect caused by the heat dissipation direction at the bottom. This design, which forms a dynamic temperature compensation band, exploits the principle of varying heat conduction density load, where thin areas near the heat source heat up or cool down first. This creates an effect similar to that of a compensating heating device (such as a heating rod or heating film), but without the need for additional control and automatically synchronizes with the internal temperature zone. This approach not only simplifies the design but also improves the uniformity and efficiency of temperature control.

[0123] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0124] In addition, in the present invention, descriptions such as "first," "second," and "one" are for descriptive purposes only and should not be understood to indicate or imply their relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0125] In the present invention, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will be able to understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0126] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in this field can implement it. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. A method for improving the temperature uniformity of a PCR plate, characterized in that: include: Construct the heat conduction differential equation through Fourier's heat conduction law; The first type of boundary condition is set based on the fixed temperature at the edge of the orifice plate; the second type of boundary condition is set based on the heat density at the edge of the orifice plate; and the third type of boundary condition is set based on the convective heat transfer process between the edge of the orifice plate and the surrounding fluid. The heat conduction differential equation is defined by the above three types of boundary conditions; Based on the thermal conductivity of the orifice plate edge material, the orifice plate cross-sectional area perpendicular to the heat flow direction, and the temperature gradient, and combined with the heat conduction differential equation, the calculation equations for unit heat and unit heat density are constructed; the temperature gradient represents the rate of change of temperature along the heat flow direction; the unit heat represents the amount of heat passing through a preset cross-sectional area per unit time; and the unit heat density represents the amount of heat passing through a unit area per unit time; The relationship between unit heat density and the thickness of the orifice plate edge material is determined by the calculation equation of unit heat and unit heat density, and based on this relationship, the influence of the orifice plate edge material thickness on the second type of boundary conditions is analyzed; Based on the analysis results of the correlation between unit heat density and the thickness of the orifice plate edge material and its influence on the second type of boundary conditions, the thickness of the orifice plate edge material is designed and set so that a temperature zone is formed at the edge of the orifice plate during the heating and cooling process.

2. A method for improving the temperature uniformity of a PCR plate according to claim 1, characterized in that: The heat conduction differential equation is constructed through Fourier's heat conduction law, including: The first formula is based on the fact that the heat conduction power per unit volume is equal to the heat source power per unit volume in steady-state heat transfer: Where Q represents the heat source power per unit volume, that is, the total heat passing through the preset cross-sectional area A per unit time; represents the heat flux vector; represents the divergence operation; The second formula is set based on Fourier's law of heat conduction: Where T is the temperature field, are the unit direction vectors in the x, y, and z directions respectively, k x ,k y ,k z are the thermal conductivity of the orifice plate edge material along the x, y, and z directions respectively; Substituting the second formula into the first formula, we get the third formula: By expanding the third formula in the rectangular coordinate system, the heat conduction differential equation is obtained:

3. A method for improving the temperature uniformity of a PCR plate according to claim 2, characterized in that: The first type of boundary condition is used to set the temperature of the orifice plate edge, and its formula is: T 边缘 =T1; where T 边缘 Indicates the temperature on the edge of the orifice plate, and T1 indicates the preset fixed temperature of the orifice plate edge; The second type of boundary condition is used to specify the heat flux per unit area at the edge of the orifice plate, and its formula is: Where, l x 、l y 、l z are the three components of the unit external normal vector on the edge of the orifice plate, indicating the direction of the orifice plate edge; q represents the unit heat density, that is, the amount of heat passing through a unit area per unit time; The third type of boundary condition is used to limit the heat exchange between the edge of the orifice plate and the surrounding fluid, and its formula is: Where, T ∞ represents the free stream temperature of the mainstream field at the edge of the orifice plate, T 表面 represents the temperature of the edge surface of the orifice plate, and h represents the convection heat transfer coefficient.

4. A method for improving the temperature uniformity of a PCR plate according to claim 3, characterized in that: The calculation equation of the unit heat is: Where A represents the cross-sectional area of ​​the orifice plate perpendicular to the direction of heat flow, Q represents the total heat passing through the preset cross-sectional area A per unit time, and λ represents the thermal conductivity of the orifice plate edge material. It represents the temperature gradient, that is, the rate of change of temperature along the direction of heat flow; The calculation equation of the unit heat density is: In the formula, q represents the unit heat density, that is, the amount of heat passing through a unit area per unit time.

5. A method for improving the temperature uniformity of a PCR plate according to claim 4, characterized in that: The relationship between the unit heat density and the thickness of the orifice plate edge material is determined by the calculation equation of unit heat and unit heat density, specifically: A thickness modulation heat conduction model is constructed to reflect the effect of the thickness change of the orifice plate edge material on heat conduction. The x-axis coordinate of the thickness modulation heat conduction model is the thickness position of the orifice plate edge material, and the y-axis coordinate is the temperature T. The thermal conductivity of the orifice edge material does not change with the change of the x-axis coordinate, and the total heat passing through the preset cross-sectional area A per unit time does not change with the x-axis coordinate, and Integrate to get the integral formula: Where x1 represents the starting position of the thickness of the material at the edge of the orifice plate, x2 represents the ending position of the thickness of the material at the edge of the orifice plate; T1 and T2 represent the temperatures at the starting position and the ending position respectively; The relationship between unit heat density and the thickness of the orifice plate edge material is obtained through the integral formula: In the formula, δ = x2-x1; in the formula, δ represents the thickness of the orifice plate edge material.

6. A PCR well plate, characterized in that include: An orifice plate body, wherein the orifice plate body is provided with an accommodating hole group, and the accommodating hole group includes a plurality of accommodating holes; The orifice plate body is provided with first edge plates on both sides along the length direction of the accommodating hole group, and the orifice plate body is provided with second edge plates and third edge plates on both ends along the length direction of the accommodating hole group; the thickness of the second edge plates and the third edge plates is less than that of the first edge plate; The thickness ratio of the first edge plate, the second edge plate and the third edge plate is set by a method for improving the temperature uniformity of a PCR well plate according to any one of claims 1 to 5.

7. A PCR well plate according to claim 6, characterized in that, When the thickness ratio of the first edge plate, the second edge plate and the third edge plate is set to 3:2:1, the heat flow direction is toward the side where the third edge plate is located; When the thickness ratio of the first edge plate, the second edge plate and the third edge plate is set to 3:1:2, the heat flow direction is toward the side where the second edge plate is located.

8. A PCR well plate according to claim 6, characterized in that, The thickness of the second edge plate and the third edge plate are both greater than a preset threshold; When the set thickness ratio does not satisfy the condition that the thickness of the second edge plate and the third edge plate are both greater than the preset threshold, the thickness relationship of the first edge plate, the second edge plate and the third edge plate is re-set based on the heat flow direction.

9. A PCR well plate according to claim 8, characterized in that, The thickness relationship between the first edge plate, the second edge plate, and the third edge plate is set based on the heat flow direction, specifically including: When setting the heat flow direction to the side where the second edge plate is located, set: Preset threshold < thickness of the second edge plate < thickness of the third edge plate < thickness of the first edge plate; When setting the heat flow direction to the side where the third edge plate is located, set: The preset threshold value < the thickness of the third edge plate < the thickness of the second edge plate < the thickness of the first edge plate.

10. A PCR well plate according to claim 6, characterized in that: The receiving hole group includes multiple rows of receiving holes, and Peltiers are provided on both sides of each row of receiving holes; Two ends of the Peltier extend from two ends of a corresponding row of accommodating holes respectively.

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