A special-shaped heat flux deep temperature measurement probe and method considering contact thermal resistance

Abstract

The present invention discloses a special-shaped heat flux deep temperature measurement probe and method taking into account contact thermal resistance. Based on the contact thermal resistance, the present invention improves the deep temperature measurement method for the special-shaped heat channel structure. An additional number of heat flux sensors can be added at the shape mutation point of the special-shaped channel, the interface of the insulation material and each side wall, and the deep temperature is predicted together with the temperature sensors and heat flux sensors at the bottom and top. The heat flux flow generated from the deep temperature measurement area of ​​the human body is transferred to the special-shaped heat flow channel through the skin surface. The heat flux sensor in the channel can be used to correct the heat flow transfer process, and the heat transfer unit can be extended to any special shape. The influence of the contact thermal resistance of flexible and rigid materials on the heat flow transfer is further considered, so that the measurement method is closer to the actual situation, and the accuracy of the deep temperature measurement method is improved in principle.

Description

Technical Field

[0001] The invention relates to a method for measuring deep temperature of a special-shaped heat flux taking contact thermal resistance into consideration, and belongs to the field of physiological signal detection and medical instruments and equipment. Background Art

[0002] Deep temperature is a crucial indicator of human health. A constant deep temperature is essential for normal metabolism and vital activities. Deep temperature reflects the temperature of the chest, major internal organs, and blood leaving the heart (pulmonary artery). As such, it is insensitive to changes in sweat, clothing, and psychological state. Therefore, among numerous physiological signals, deep temperature is widely used as a key indicator for assessing health.

[0003] Existing wearable, continuous deep temperature measurement devices for home use are highly inaccurate. Widely used non-invasive or minimally invasive measurement methods on the market all use axillary, ear, or forehead temperatures to approximate deep temperature, resulting in large errors and being significantly affected by ambient temperature and the measurement site.

[0004] Existing home monitoring wearable devices that claim to continuously measure deep temperature on the skin are very inaccurate: those widely sold on the market are used to measure deep temperature; 3M and Terumo have both launched sensors that measure deep temperature based on the zero heat flux principle, but they require wires and other means to provide energy to maintain heating and accurately control the feedback loop. This method is difficult to implement in wearable devices, and most application scenarios are clinical or intraoperative monitoring in hospitals.

[0005] Currently, most research on wearable deep temperature measurement methods uses heat flow technology based on skin temperature. Modeling methods are used to invert the temperature and heat flow at the skin measurement location. The final deep temperature is obtained by reversely calculating the heat transfer process from deep tissue to the skin surface and then through a single heat transfer unit to the environment. Typical heat flow technologies for deep temperature measurement include single-channel heat flow technology and dual-channel heat flow technology.

[0006] The stability and establishment of the heat flow channel are crucial to the calculation of deep temperature. Currently, most measurement devices are designed as simple cylindrical heat flux channels, which require a larger sensor volume to maintain the temperature and stability of the heat flow channel. However, the space in the wearable structure may be affected by the size of the device and the heat source of the internal components. Under certain conditions, only special-shaped heat flux channels can be used for deep temperature measurement. At the same time, the thermal insulation structure cannot completely isolate the influence of the external temperature field, which will have a negative effect on the measurement of deep temperature. At the same time, there is a flexible or rigid interface contact between the wearable device and the human body. Therefore, how to improve the deep temperature measurement method for the special-shaped heat channel structure based on the consideration of contact is a technical problem that the present invention needs to solve. Summary of the Invention

[0007] The purpose of the present invention is to solve the influence of the special-shaped heat channel structure on deep temperature measurement in the prior art and to provide a special-shaped heat flux deep temperature measurement method taking into account the contact thermal resistance.

[0008] The technical solutions specifically adopted in the present invention are as follows:

[0009] In a first aspect, the present invention provides a special-shaped heat flux deep temperature measurement probe taking into account contact thermal resistance, which includes a heat transfer unit, a heat insulation unit, a temperature sensor and a heat flux sensor;

[0010] The heat transfer unit is a special-shaped structure made of a single material;

[0011] The heat insulation unit completely covers the top end surface and side surfaces of the heat transfer unit, and the bottom surface of the heat transfer unit is exposed from the heat insulation unit and is flush with the bottom surface of the heat insulation unit; the heat insulation unit is composed of a single material layer or a combination of two or more material layers;

[0012] There are two temperature sensors, one on the top end face and one on the bottom end face of the heat transfer unit;

[0013] The heat flux sensor includes three types: a first heat flux sensor, a second heat flux sensor, and a third heat flux sensor; wherein

[0014] A first heat flux sensor is arranged at each of the top end surface and the bottom end surface of the heat transfer unit to detect the heat flux passing through the end surface;

[0015] A second heat flux sensor is arranged at the interface between the side surface of the heat transfer unit and each type of heat insulation unit material to detect the heat flux passing through the interface;

[0016] The third heat flux sensor is arranged inside the heat transfer unit, with at least one, and a third heat flux sensor is arranged at each location in the heat transfer unit where the heat flow direction suddenly changes due to a change in the unit shape and where the heat flow size suddenly changes due to a sudden change in the external insulation material.

[0017] As a preferred embodiment of the first aspect, the special-shaped structure of the heat transfer unit is formed by splicing together a plurality of regular structural monomers, and the shapes of all regular structural monomers are one or more of a column, a platform, a ring and a sphere.

[0018] As a preferred embodiment of the first aspect, the arrangement position of the third heat flux sensor arranged inside the heat transfer unit is related to the form of the heat transfer unit and the heat insulation unit, specifically:

[0019] If the heat insulation unit is composed of a single material layer and there is no location inside the heat transfer unit where the heat flow direction suddenly changes due to a change in the unit shape, a third heat flux sensor is arranged inside the heat transfer unit to detect the heat flux of the heat flow in the heat transfer unit;

[0020] If there is a sudden change in heat flow direction due to a change in the unit shape in the heat insulation unit, a third heat flux sensor is arranged at each sudden change in heat flow direction inside the heat transfer unit to detect the heat flux when the heat flow in the heat transfer unit passes through the sudden change position;

[0021] If the thermal insulation unit is composed of two or more material layers, the plane where the interface between any two adjacent different material layers is located and the heat transfer unit form an intersection surface with a sudden change in heat flux size, and a third heat flux sensor is arranged in each of the intersection surfaces to detect the heat flux passing through the intersection surface.

[0022] As a preferred embodiment of the above-mentioned first aspect, the centers of the sensor planes of the third heat flux sensors inside the heat transfer unit are arranged along the axis of the heat flow channel inside the heat transfer unit, and the planes of the third heat flux sensors arranged at the position where the heat flow direction suddenly changes face the heat flow direction, and the planes of the third heat flux sensors arranged at the position where the heat flow magnitude suddenly changes coincide with the intersection surface.

[0023] As a preferred embodiment of the above-mentioned first aspect, the insulation material used in the insulation unit is one or more of glass fiber, asbestos, rock wool, gel felt, and vacuum cavity, and the thermal conductivity of the insulation material is smaller than the thermal conductivity of the heat transfer material used in the heat transfer unit.

[0024] As a preferred embodiment of the first aspect, a bonding element is provided on the bottom end surface of the thermal insulation unit that contacts the skin, for bonding the probe to the skin.

[0025] As a preferred embodiment of the first aspect, the bottom end surface of the thermal insulation unit is made of flexible material or rigid material, preferably flexible material; the flexible material is preferably graphene; and the rigid material is preferably Corning glass.

[0026] As a preference of the first aspect above, the side surfaces and top end surfaces of the thermal insulation unit are covered with a thermal radiation shielding layer.

[0027] As a preferred embodiment of the first aspect, the shielding layer is a uniform metal material layer, preferably aluminum alloy or nickel silver; the thickness of the shielding layer is preferably controlled to be less than 1 mm.

[0028] In a second aspect, the present invention provides a method for measuring deep temperature using any of the measuring probes described in the first aspect, wherein the method comprises: pressing the bottom surface of the measuring probe against the skin surface of the part to be measured, obtaining the pressing pressure P applied to the measuring probe and the detection data of all temperature sensors and heat flux sensors in the measuring probe, and calculating the deep temperature T of the part to be measured. c :

[0029] T c =(R+ΔR c )* HFS +T s +m* a

[0030] Where: R is the thermal resistance between the skin and the deep temperature at a specified compression pressure. s And the contact thermal resistance R between the skin and the part to be tested c The sum is the pre-calibrated value; ΔR c is the contact thermal resistance R related to the pressing pressure P c The change is determined by the pre-calibrated ΔR c The mapping relationship between T and P is determined; s is the skin surface temperature of the measured part; T a is the ambient temperature of the measuring probe during measurement; m is the ambient temperature T a The relevant correction coefficient is a pre-calibrated value; U HFS is the heat flux value within the heat transfer unit, which is obtained by calibrating the heat flux values ​​detected by all heat flux sensors inside the heat transfer unit. The calibration formula is: Where k i is the pre-calibrated i-th calibration coefficient, U HFSi is the heat flux value detected by the i-th heat flux sensor inside the heat transfer unit, and n is the total number of heat flux sensors inside the heat transfer unit.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] Taking contact into consideration, the present invention improves the deep temperature measurement method for the special-shaped heat channel structure, adds an appropriate number of temperature sensors and heat flux sensors to the heat transfer channel and the heat insulation unit, and adds an additional contact thermal resistance term to the sensing model. The heat flux generated from the deep temperature measurement area of ​​the human body is transferred to the special-shaped heat flow channel through the skin surface. The heat flux sensor in the channel can be used to correct the heat flow transfer process, and the influence of the contact thermal resistance of flexible and rigid materials on the heat flow transfer can be further considered, so that the measurement method is closer to the actual situation, and the accuracy of the deep temperature measurement method is improved in principle. Therefore, the present invention is an improved solution for measuring deep temperature under the special-shaped heat channel structure by changing the sensing model and adding additional heat flux sensors. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a schematic side cross-sectional view of a measuring probe for determining the deep temperature of a living being according to the present invention;

[0034] Figure 2 Schematic diagram of vertical / horizontal heat flux of the probe;

[0035] Figure 3 is a three-dimensional schematic diagram of the probe;

[0036] Reference numerals in the figure: 1. heat transfer unit; 1a. first temperature sensor; 1b. first end face heat flux sensor; 2a. second temperature sensor; 2b. second end face heat flux sensor; s1…sn. side wall heat flux sensor; h1…hn. internal heat flux sensor; i1…in. thermal insulation material layer; z1…zn. central axis of the heat transfer unit; d1. bottom end face of the heat transfer unit (the end face in contact with the skin surface); u1. top end face of the heat transfer unit; e1. side face of the heat transfer unit; e2. side face of the thermal insulation unit; u2. top end face of the thermal insulation unit; 2. shielding layer; 3. vertical heat flow from the skin layer to the heat transfer unit; 4. heat flow through the heat transfer unit. DETAILED DESCRIPTION

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. The technical features in the various embodiments of the present invention can be combined accordingly without conflicting with each other.

[0038] In the description of the present invention, it should be understood that when an element is considered to be "connected" to another element, it can be directly connected to the other element or indirectly connected, that is, there are intermediate elements. On the contrary, when an element is said to be "directly" connected to another element, there are no intermediate elements.

[0039] In the description of the present invention, it should be understood that the terms "first" and "second" are used solely for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly specifying the number of technical features being described. Therefore, features defined as "first" or "second" may explicitly or implicitly include at least one of such features.

[0040] The present invention provides a special-shaped heat flux deep temperature measurement probe that takes contact thermal resistance into consideration. Its core components include a heat transfer unit, a heat insulation unit, a temperature sensor, and a heat flux sensor. The following describes in detail the installation form and the matching relationship between these components.

[0041] The heat transfer unit is a special-shaped structure made of a single material, which can be made of a heat transfer material with a high heat transfer coefficient. The heat transfer unit serves as a heat flux channel. The special-shaped structure of the heat transfer unit can be composed of multiple regular structural units, with all regular structural units taking one or more of the following shapes: a cylinder, a platform, a ring, and a sphere. For example, a curved special-shaped structure can be formed by continuously connecting multiple cylinders in a staggered horizontal and vertical manner. Alternatively, cylinders and platforms can be connected to form a special-shaped structure with abrupt changes in cross-sectional shape. This special-shaped heat flux channel has applications in wearable devices with internal heat sources, which require special-shaped heat flux channels for deep temperature measurement. However, compared to regular cylindrical heat flux channels, deep temperature measurement with this special-shaped heat flux channel is more difficult, requiring a specifically designed measurement method. The top and bottom surfaces of the heat transfer unit should be kept as parallel as possible to eliminate interference from horizontal heat and improve the accuracy of the results.

[0042] In this measurement probe, the thermal insulation unit completely wraps around the top end face and side faces of the heat transfer unit, and the bottom face of the heat transfer unit is exposed from the thermal insulation unit and is flush with the bottom face of the thermal insulation unit. The thermal insulation unit can be composed of a single material layer or a combination of two or more material layers. The thermal conductivity of the thermal insulation material used in the thermal insulation unit should be as low as possible. It can be one or more of the following materials: glass fiber, asbestos, rock wool, gel felt, vacuum cavity, etc. In principle, it is necessary to ensure that the thermal conductivity of the thermal insulation material is less than that of the heat transfer material used in the heat transfer unit to prevent horizontal heat flow and reduce external environmental interference. Experimental results have shown that the use of closed, air-evacuated cavities in the thermal insulation unit is the most effective way to prevent horizontal heat flow in deep temperature probes.

[0043] The probe also includes two temperature sensors, one located on the top and one on the bottom of the heat transfer unit. The bottom sensor measures skin surface temperature, while the top sensor helps determine if the insulation unit has failed and needs replacement. When the top sensor measures a temperature close to ambient temperature, the insulation unit has failed.

[0044] The heat flux sensors in the measuring probe include three types: a first heat flux sensor, a second heat flux sensor, and a third heat flux sensor. The arrangements of the three types of heat flux sensors are as follows:

[0045] A first heat flux sensor can be positioned at each of the top and bottom end surfaces of the heat transfer unit to detect heat flux passing through the end surfaces. The first heat flux sensors can be positioned in close proximity to the end surfaces. The first heat flux sensors at the top and bottom end surfaces of the heat transfer unit are used to calculate heat flux transferred from deep within the body to the skin through the heat flow channels within the heat transfer unit.

[0046] As for the second heat flux sensor, one can be placed at the interface between the side of the heat transfer unit and each type of insulation unit material to detect the heat flux passing through the interface. The second heat flux sensor can be placed in close contact with the interface.

[0047] The second heat flux sensor at the interface and the first heat flux sensors at each end of the heat transfer unit can help determine if the insulation unit has failed and locate the failure. These heat flux sensors can also be used to determine the optimal structural form during the design phase of the heat transfer unit's special-shaped structure.

[0048] As for the third heat flux sensor, the third heat flux sensor is arranged inside the heat transfer unit, there is at least one, and a third heat flux sensor is arranged at each position in the heat transfer unit where the heat flow direction suddenly changes due to a change in the unit shape and where the heat flow size suddenly changes due to a sudden change in the external insulating material.

[0049] The arrangement position of the third heat flux sensor arranged inside the heat transfer unit is related to the form of the heat transfer unit and the heat insulation unit, specifically:

[0050] i) If the heat insulation unit is composed of a single material layer and there is no sudden change in the heat flow direction due to a change in the unit shape, a third heat flux sensor is arranged inside the heat transfer unit to detect the heat flux of the heat flow in the heat transfer unit;

[0051] ii) If there is a sudden change in heat flow direction at a location in the heat insulation unit due to a change in unit shape, a third heat flux sensor is arranged at each sudden change in heat flow direction within the heat transfer unit to detect the heat flux when the heat flow in the heat transfer unit passes through the sudden change location;

[0052] iii) If the thermal insulation unit is composed of two or more material layers, the plane where the interface between any two adjacent different material layers is located and the heat transfer unit form an intersection surface with a sudden change in heat flux, and a third heat flux sensor is arranged in each of the intersection surfaces to detect the heat flux passing through the intersection surface.

[0053] It should be noted that the third heat flux sensor arranged in i) above can be arranged parallel to the bottom surface of the heat transfer unit, and its height can be set at the middle position of the heat transfer unit. As for the third heat flux sensor arranged in ii), the change in the unit shape that causes the sudden change in heat flow direction in the present invention is caused by the non-smooth corner of the heat transfer unit body. For example, when two square columns are continuously spliced ​​at right angles or other angles, a non-smooth transition corner will be generated at the splicing position, and this position will cause a sudden change in heat flow direction; similarly, when a frustum is spliced ​​with a cylinder, a non-smooth transition corner will also be generated at the splicing position, and this position will also cause a sudden change in heat flow direction. These positions where sudden changes in heat flow direction occur require the placement of a third heat flux sensor, thereby ensuring that every part of the special-shaped probe is monitored and eliminating the interference of the special-shaped structure on the deep temperature. In addition, for the third heat flux sensor arranged in iii), the intersection surface at the location where the heat flux size suddenly changes in the present invention is caused by the change of the insulation unit material outside the heat transfer unit. Different insulation materials have different insulation coefficients, which will affect the outward transfer of heat in the heat transfer unit. The third heat flux sensor here can be arranged along the intersection surface. In actual operation, the interface between the two different material layers in the insulation unit can be extended to form an intersection surface with the heat transfer unit, and then the third heat flux sensor is arranged on this intersection surface.

[0054] The function of the third heat flux sensor is to detect the heat flow in the heat channel and then calibrate and calculate the actual heat flow value U in the heat channel. HFS .

[0055] To ensure the accuracy of the third heat flux sensor's detection data, the sensor plane centers of all third heat flux sensors within the heat transfer unit can be arranged along the axis of the heat flow channel within the heat transfer unit. The planes of third heat flux sensors located at locations where the heat flow direction suddenly changes face the heat flow direction, while the planes of third heat flux sensors located at locations where the heat flow magnitude suddenly changes coincide with the aforementioned intersecting plane. It should be noted that the planes of the third heat flux sensors face the heat flow direction. In principle, it is best if the sensor planes are perpendicular to the heat flow direction. However, due to manufacturing constraints and the difficulty in determining the actual heat flow direction, a certain angle between the two is permitted.

[0056] In addition, when in use, the measuring probe can be directly pressed on the skin surface of the part to be measured, and the pressure can be kept constant to read the internal sensor data. In order to facilitate fixing the measuring probe on the skin, an adhesive element can be provided on the bottom end face of the thermal insulation unit in contact with the skin, so that the probe can be attached to the skin by means of an adhesive element. Of course, it can also be fixed to the skin by means of a bandage or other pressing methods. However, since the pressure on the measuring probe is related to the contact thermal resistance between the skin and the part to be measured, in order to subsequently calculate the deep temperature of the part to be measured, it is necessary to obtain the pressing pressure on the measuring probe in advance. The pressure can be measured by clamping a pressure sensor between the measuring probe and the skin, or by measuring it through an external device. If a clamping pressure sensor is used, the pressure sensor can be pre-set on the bottom end face of the thermal insulation unit of the measuring probe, or it can be placed separately between the bottom end face of the thermal insulation unit and the skin when in use.

[0057] The bottom end surface of the thermal insulation unit that contacts the skin is made of either a flexible or rigid material, preferably a flexible material. The bottom end surface of the thermal insulation unit that contacts the skin can be made of either a flexible or rigid material. Flexible materials can include, for example, graphene, while rigid materials can include, for example, Corning glass. Preferably, the material used for the bottom end surface of the thermal insulation unit that contacts the skin has as high a thermal conductivity as possible to avoid excessive contact thermal resistance and improve measurement accuracy.

[0058] Furthermore, to reduce heat loss from the insulation unit through thermal radiation, the sides and top surfaces of the insulation unit are covered with a thermal radiation shielding layer. This shielding layer can be made of a uniform metal material, preferably aluminum alloy or nickel silver. Preferably, the metal layer is polished. Such materials have a low thermal emissivity and can effectively reduce temperature fluctuations within the insulation due to thermal radiation. The thickness of the shielding layer is preferably controlled to be less than 1 mm.

[0059] The above-mentioned special-shaped heat flux deep temperature measurement probe that takes into account contact thermal resistance can be used to obtain sensor data related to deep temperature, and then used to calculate deep temperature. Therefore, based on this measurement probe, the present invention also provides a deep temperature measurement method, which is as follows: pressing the bottom surface of the measurement probe on the skin surface of the part to be measured, obtaining the pressing pressure P applied to the measurement probe and the detection data of all temperature sensors and heat flux sensors in the measurement probe, and calculating the deep temperature T of the part to be measured. c , the deep temperature is calculated as follows:

[0060] T c =(R+ΔR c )* HFS +T s +m* a

[0061] Where: R is the thermal resistance between the skin and the deep temperature at a specified compression pressure. s And the contact thermal resistance R between the skin and the part to be tested c The sum is the pre-calibrated value; ΔR c is the contact thermal resistance R related to the pressing pressure P c The change is determined by the pre-calibrated ΔR c The mapping relationship between T and P is determined; s is the skin surface temperature of the measured part; T a is the ambient temperature of the measuring probe during measurement; m is the ambient temperature T a The relevant correction coefficient is a pre-calibrated value; U HFS is the heat flux value within the heat transfer unit, which is obtained by calibrating the heat flux values ​​detected by all heat flux sensors inside the heat transfer unit. The calibration formula is: Where k i is the pre-calibrated i-th calibration coefficient, U HFSi is the heat flux value detected by the i-th heat flux sensor inside the heat transfer unit, and n is the total number of heat flux sensors inside the heat transfer unit.

[0062] In the deep temperature calculation formula described above, the present invention significantly reduces the interference of contact thermal resistance on the result by separating and calibrating the change in contact thermal resistance under pressure changes and incorporating this change into the thermal resistance term. Furthermore, the probe incorporates heat flux sensors at locations within the heat transfer channel where sudden changes in heat flow direction and magnitude may occur. The detected heat flux is multiplied by a calibration coefficient to produce a shape-corrected heat flux value, effectively eliminating interference from irregular shapes and external point heat sources. Finally, given that insulation materials cannot completely insulate and are affected by changes in ambient temperature, a correction term related to ambient temperature has been added to eliminate external interference.

[0063] It should be noted that the specified pressure for determining the R value can be selected according to actual conditions, and the R value can be determined in the calibration procedure using the sensor data obtained at the specified pressure. c , which is related to the pressing pressure P on the measuring probe. Therefore, after determining the R value, the pressing pressure can be changed to calibrate the contact thermal resistance R under different pressing pressures P. c Change ΔR c , establish a lookup table with a mapping relationship, so that the corresponding ΔR can be found according to the actual applied P value in actual application. c The skin surface temperature T of the measured part s The ambient temperature T can be measured by the temperature sensor at the bottom end of the heat transfer unit. a It can be determined by external temperature detection equipment. The correction coefficient m can be determined by fitting the sensor data by changing different ambient temperatures in the calibration procedure. HFS The calibration coefficient k in the calibration formula i This can be determined in the calibration procedure by fixing the external heat source position and then varying the deep temperature and acquiring sensor data for fitting.

[0064] It can be seen that the above-mentioned deep temperature measurement method is particularly effective for special-shaped heat channel structures. By adding an appropriate number of temperature sensors and heat flow sensors to the heat transfer channel and the insulation unit, and measuring the deep temperature T c A contact thermal resistance term is additionally added to the calculation model, so that the heat flux generated from the deep temperature measurement area of ​​the human body is transferred through the skin surface to the special-shaped heat flow channel. The heat flux sensor in the channel can be used to correct the heat flow transfer process, thereby taking into account the influence of contact thermal resistance on heat flow transfer, making the measurement method closer to the actual situation and improving the accuracy of the deep temperature measurement method in principle.

[0065] In addition, the above-mentioned deep temperature measurement method can be integrated into a corresponding computing unit to form a deep temperature measurement device. The deep temperature measurement device includes the aforementioned measuring probe and computing unit. The computing unit can obtain the detection data of all internal temperature sensors and heat flux sensors when the measuring probe is pressed against the skin surface of the measured part with a pressing pressure P, and calculate the deep temperature T of the measured part. c , deep temperature T c The calculation formula is shown above. This calculation unit can be a data processing unit such as a chip integrated on the probe, or it can be a host computer or cloud server that has a data communication connection with the measurement probe, without limitation.

[0066] The specific implementation of the above-mentioned special-shaped heat flux deep temperature measurement probe and measurement method considering contact thermal resistance of the present invention is demonstrated below through embodiments.

[0067] Example

[0068] like Figure 1 As shown, in a preferred embodiment of the present invention, a measuring probe for deep temperature measurement of special-shaped heat flux is shown, and its main components include a heat transfer unit 1, a heat insulation unit (including a heat insulation material layer i1, a heat insulation material layer i2, and a heat insulation material layer i3), a first temperature sensor 1a, a second temperature sensor 2a, a first end surface heat flux sensor 1b, a second end surface heat flux sensor 2b, four internal heat flux sensors are recorded as h1, h2, h3, and h4, and three side wall heat flux sensors are recorded as s1, s2, and s3.

[0069] The heat transfer unit 1 is a special-shaped structure. In this embodiment, it is a rectangular heat transfer channel with a Z-shaped longitudinal section. It is composed of three square pillars with identical cross-sections, connected in a continuous pattern, with adjacent pillars perpendicular to each other. This heat transfer unit 1 effectively utilizes the lateral space of the equipment, enabling heat flux establishment and deep temperature calculation within a limited vertical space. Heat transfer unit 1 forms a special-shaped heat flow channel.

[0070] Four internal heat flux sensors h1, h2, h3, and h4 are embedded in the heat transfer unit 1. Each sensor's center is positioned on the central axis of the heat flow channel to ensure that the measured heat flux value is as close as possible to the heat flux value for the entire channel. Each internal heat flux sensor is located at a specific location within the heat transfer unit 1 where the cross-sectional shape or orientation of the heat flow channel undergoes a sudden change, causing a change in the direction of heat flow through the location. This is why the internal heat flux sensors are necessary. Figure 2 Shown Figure 1The schematic diagram of the vertical and horizontal heat flux within the probe shows that the locations of the four internal heat flux sensors h1, h2, h3, and h4 all experience sudden changes in heat flow direction due to the sudden change in unit shape. To accurately measure these locations where the heat flow direction suddenly changes, the sensor planes of the four internal heat flux sensors h1, h2, h3, and h4 should be oriented as much as possible towards the heat flow direction at their respective locations. In addition, since the insulation unit contains three different layers of thermal insulation material—insulation layer i1, insulation layer i2, and insulation layer i3—it is necessary to arrange internal heat flux sensors at the intersection of the plane where the interface between insulation layer i1 and insulation layer i2 intersects with heat transfer unit 1. Internal heat flux sensors are also arranged at the intersection of the plane where the interface between insulation layer i2 and insulation layer i3 intersects with heat transfer unit 1 to detect the heat flux values ​​at these two intersections where the heat flux magnitude suddenly changes. However, in this embodiment, the two interface surfaces of the three-layer insulation material coincide with the two shape mutation positions of the heat transfer unit 1. Therefore, the internal heat flux sensor h1 and the internal heat flux sensor h2 actually also play the role of measuring the heat flow at the two intersecting surfaces, and there is no need to repeatedly set up the internal heat flux sensor.

[0071] In the probe of this embodiment, three sidewall heat flux sensors s1, s2, and s3 are positioned at the three interfaces formed between the side surface e1 of the heat transfer unit 1 and the three insulation materials. The sensor planes of the three sidewall heat flux sensors are aligned with the interfaces. In the probe of this embodiment, a first temperature sensor 1a, a first end surface heat flux sensor 1b, and a second temperature sensor 2a, a second end surface heat flux sensor 2b are embedded in the bottom end surface d1 and the top end surface u1 of the heat transfer unit 1, respectively. The temperature sensors and end surface heat flux sensors on each end surface are positioned symmetrically about the central axis of the corresponding end surface.

[0072] At the same time, the insulation material layer i1, the insulation material layer i2, and the insulation material layer i3 in the insulation unit need to completely wrap the top end surface u1 and the side surface e1 of the heat transfer unit 1. The bottom surface of the heat transfer unit 1 is exposed from the insulation unit and is flush with the bottom surface of the insulation unit. The insulation materials used in each insulation material layer i1, i2, and i3 in the insulation unit can be the same or different, but the insulation materials of two adjacent insulation material layers are different. The thermal conductivity of the material in the insulation material layer is required to be as low as possible. In principle, it is necessary to ensure that the thermal conductivity of the insulation material is less than the thermal conductivity of the heat transfer material used in the heat transfer unit 1. At the same time, the inner wall of the insulation unit and the heat transfer unit are kept in close contact with each other as much as possible to improve the insulation performance and minimize the occurrence of horizontal heat flow.

[0073] When in use, the aforementioned measuring probe can be pressed directly against the skin surface. However, to reduce contact thermal resistance and increase heat exchange rate, a highly thermally conductive, flexible filler material can be placed between the surface skin and the deep temperature probe. However, the bottom end surface d1 in contact with the skin must be completely covered with the filler material. Further securing can be achieved with a strap. Of course, other adhesive or fixing methods can also be used if necessary, such as placing adhesive elements on the bottom end surface of the thermal insulation unit.

[0074] In addition, if the filling material is flexible and has high thermal conductivity, the contact thermal resistance can be ignored when the thermal contact is sufficient. However, if it is rigid but the microscopic contact is a discrete area element, the heat will pass through the air gap layer between the non-contact interfaces by heat conduction. At this time, the contact thermal resistance cannot be ignored and should be reflected in the deep temperature sensing model.

[0075] When the bottom end face of the measuring probe is pressed against the skin surface corresponding to the deep location to be measured, the vertical heat flux 3 transmitted from the skin layer to the heat transfer unit passes through the skin surface, through the filler material (if any) between the skin interface and the probe, and then enters the heat transfer unit. Because the thermal conductivity of the insulation material is lower than that of the heat transfer unit, the heat flow tends to flow through areas with lower thermal resistance. Therefore, the heat flow entering the channel is transmitted along the path of the irregular heat flow channel, ultimately establishing a stable heat flow channel 4. During this process, the heat flow flowing through the irregular channel is converted into heat flux values ​​at each location by the four heat flux sensors h1, h2, h3, and h4 inside the channel. Ideally, the heat flux values ​​obtained by these four heat flux sensors are consistent. However, because the insulation material cannot completely block heat, the four heat flux values ​​are not necessarily completely equal. The sidewall heat flux sensors s1, s2, and s3 embedded in each sidewall of the heat transfer unit 1 ensure that every part of the irregular probe is monitored, eliminating interference caused by imperfect insulation material and the shape of the channel itself. When the insulation layer fails, the sidewall heat flux sensors can detect the failure. In addition, the top temperature sensor 2a can also be used to detect whether the insulation layer above is damaged. When damage occurs, its temperature sensing value will be close to the ambient temperature.

[0076] In addition, thermal radiation is also an important component of the heat transfer path, and the probe of the present invention also needs to block thermal radiation. In this embodiment, the side e2 and top end surface u2 of the thermal insulation material layers i1, i2, and i3 of the thermal insulation unit are continuously covered with a thermal radiation shielding layer 2, which can reduce the thermal radiation heat exchange between the inside of the temperature probe and the outside world. In this embodiment, the shielding layer adopts a metal tin layer with a reflection coefficient of less than 0.1, which can effectively reduce the heat loss caused by the radiation path and ensure the effective establishment of a heat flow channel based on heat conduction. At the same time, the thickness of the shielding layer is less than 1 mm, which can minimize the volume of the probe and effectively utilize the equipment space.

[0077] The measuring principle of the measuring probe is based on the heat flow method, which will be described in detail below. For the sake of convenience, the value obtained by the first temperature sensor 1a at the skin is recorded as T s , parameter R s , R c They are the thermal resistance between the skin and the deep temperature, and the contact thermal resistance between the skin and the sensor to be measured. R is the sum of the thermal resistance between the skin and the deep temperature, and the contact thermal resistance between the skin and the sensor to be measured under stable pressure. ΔR c is the change in contact thermal resistance between the skin and the sensor's measured area when pressure changes. HFS It is the heat flow value corrected by multiple heat flow sensors in the channel. For the heat flow transferred from deep temperature to the skin, it is defined as follows:

[0078]

[0079] Therefore, the deep temperature T c It can be calculated by the temperature sensor and heat flow sensor on the skin surface. The sensing model can be constructed as follows:

[0080] T c =(R s +R c )* HFS +T s =(R+ΔR c )* HFS +T s

[0081] In addition, due to T c It is also related to the ambient temperature, so the above sensing model can further add a calibration item for the ambient temperature. Therefore, in this embodiment, the deep temperature T based on the heat flow method is finally adopted. c The calculation formula can be expressed as:

[0082] T c =(R+ΔR c )* HFS +T s+m* a

[0083] Where: R is the thermal resistance between the skin and the deep temperature at a specified compression pressure. s And the contact thermal resistance R between the skin and the part to be tested c The sum is the pre-calibrated value; ΔR c is the contact thermal resistance R related to the pressing pressure P c The change is determined by the pre-calibrated ΔR c The mapping relationship between T and P is determined; s is the skin surface temperature of the measured part; T a is the ambient temperature of the measuring probe during measurement; m is the ambient temperature T a The relevant correction coefficient is a pre-calibrated value; U HFS It is the heat flux value in the heat transfer unit 1, which is obtained by calibrating the heat flux values ​​detected by all heat flux sensors inside the heat transfer unit 1.

[0084] Before using the above-mentioned measuring probe, various parameters in the sensing model need to be calibrated. The calibration procedure is carried out in the following order:

[0085] First, R and ΔR c When the probe is pressed on the skin with a stable pressure P, the contact thermal resistance R c With R s The sum of the two is recorded as R. At this time, the core temperature is changed to calibrate the thermal resistance, and the R value can be obtained when the pressing pressure P is stable. After that, the pressing pressure P on the probe is changed, because only the contact thermal resistance R c It will change with the pressure P, so we separate and calibrate this part to get ΔR under different pressure P conditions. c A mapping relationship table can be established to query the corresponding ΔR according to the applied pressing pressure P. c It should be noted that, in this embodiment, the pressing pressure received by the probe can be achieved by placing a pressure sensor between the probe and the skin.

[0086] Then the heat flux value U in the special-shaped structure HFS Calibration is performed. The detection values ​​of the four internal heat flux sensors h1, h2, h3, and h4 added to the special-shaped heat flux channel in the above preferred embodiment are respectively recorded as U HFS1 、U HFS2 、U HFS3 、U HFS4 , then when the special-shaped structure has no effect on the stability and establishment of the heat flux channel, the heat flux in the channel should be equal, that is, U HFS =U HFS1 =U HFS2 =UHFS3 =U HFS4 However, when the special-shaped structure affects the stability and establishment of the heat flux channel, it is necessary to use the heat flux sensor in the channel to calibrate the real heat flux sensor, that is,

[0087] U HFS =a*U HFS1 +bu HFS2 +c* HFS3 +d* HFS4

[0088] Among them, a, b, c, and d are calibration coefficients related to the geometric structure of the special-shaped channel. Assuming that the external heat source is a point heat source and heat is transferred from the center to the periphery, the temperature difference between the four can be reversed to obtain the corresponding point heat source position, and the calibration coefficients a, b, c, and d corresponding to the heat source position at this time can be obtained. The heat flux sensor value is calibrated using the calibration coefficients. In the actual calibration process, after fixing the external heat source, different deep temperatures can be continuously changed, and then the detection data U of the four internal heat flux sensors h1, h2, h3, and h4 can be obtained. HFS1 、U HFS2 、U HFS3 、U HFS4 , and simultaneously obtain the detection data U of the first end surface heat flux sensor 1b and the second end surface heat flux sensor 2b HFSd1 、U HFSu2 , used to fit the four calibration coefficients a, b, c, and d. In each fitting sample, U HFS For U HFSd1 、U HFSu2 The average value of .

[0089] In addition, when other conditions are fixed, the coefficient m is calibrated continuously, and only the ambient temperature is changed from 5°C to 40°C. A set of discrete points about the ambient temperature and the formula error can be obtained, and the correction coefficient m can be fitted using the least squares regression method.

[0090] The embodiment described above is only a preferred solution of the present invention, but it is not intended to limit the present invention. Ordinary technicians in the relevant technical field can also make various changes and modifications without departing from the spirit and scope of the present invention. For example, the heat flux sensors and side wall heat flux sensors at each interface in the channel are deleted and adjusted. The materials used for each component and the filling material between the probe and the skin can also be selected according to actual conditions, as long as they can meet the corresponding functional requirements. In addition to the Z-shaped special-shaped channel, the heat transfer unit of the present invention can also adopt other special-shaped forms. Therefore, all technical solutions obtained by equivalent replacement or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A special-shaped heat flux deep temperature measurement probe considering contact thermal resistance, characterized in that: It includes a heat transfer unit, a heat insulation unit, a temperature sensor and a heat flux sensor; The heat transfer unit is a special-shaped structure made of a single material; The heat insulation unit completely covers the top end surface and side surfaces of the heat transfer unit, and the bottom surface of the heat transfer unit is exposed from the heat insulation unit and is flush with the bottom surface of the heat insulation unit; the heat insulation unit is composed of a single material layer or a combination of two or more material layers; There are two temperature sensors, one on the top end face and one on the bottom end face of the heat transfer unit; The heat flux sensor includes three types: a first heat flux sensor, a second heat flux sensor, and a third heat flux sensor; in A first heat flux sensor is arranged at each of the top end surface and the bottom end surface of the heat transfer unit to detect the heat flux passing through the end surface; A second heat flux sensor is arranged at the interface between the side surface of the heat transfer unit and each type of heat insulation unit material to detect the heat flux passing through the interface; The third heat flux sensor is arranged inside the heat transfer unit, with at least one, and a third heat flux sensor is arranged at each location in the heat transfer unit where the heat flow direction suddenly changes due to a change in the unit shape and where the heat flow size suddenly changes due to a sudden change in the external insulation material.

2. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 1, characterized in that: The special-shaped structure of the heat transfer unit is formed by splicing together a plurality of regular structural monomers, and the shapes of all the regular structural monomers are one or more of a column, a platform, a ring and a sphere.

3. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 1, characterized in that: The arrangement position of the third heat flux sensor arranged inside the heat transfer unit is related to the form of the heat transfer unit and the heat insulation unit, specifically: If the heat insulation unit is composed of a single material layer and there is no location inside the heat transfer unit where the heat flow direction suddenly changes due to a change in the unit shape, a third heat flux sensor is arranged inside the heat transfer unit to detect the heat flux of the heat flow in the heat transfer unit; If there is a sudden change in heat flow direction due to a change in the unit shape in the heat insulation unit, a third heat flux sensor is arranged at each sudden change in heat flow direction inside the heat transfer unit to detect the heat flux when the heat flow in the heat transfer unit passes through the sudden change position; If the thermal insulation unit is composed of two or more material layers, the plane where the interface between any two adjacent different material layers is located and the heat transfer unit form an intersection surface with a sudden change in heat flux size, and a third heat flux sensor is arranged in each of the intersection surfaces to detect the heat flux passing through the intersection surface.

4. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 3, characterized in that: The sensor plane centers of the third heat flux sensors inside the heat transfer unit are all arranged along the axis of the heat flow channel inside the heat transfer unit, and the plane of the third heat flux sensor arranged at the position where the heat flow direction suddenly changes faces the heat flow direction, and the plane of the third heat flux sensor arranged at the position where the heat flow magnitude suddenly changes coincides with the intersection surface.

5. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 1, characterized in that: The thermal insulation material used in the thermal insulation unit is one or more of glass fiber, asbestos, rock wool, gel felt, and vacuum cavity, and the thermal conductivity of the thermal insulation material is smaller than the thermal conductivity of the heat transfer material used in the heat transfer unit.

6. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 1, characterized in that: The bottom end surface of the heat insulation unit in contact with the skin is provided with an adhesive element for adhering the probe to the skin.

7. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 1, characterized in that: The bottom end surface of the heat insulation unit is made of flexible material.

8. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 7, characterized in that: The flexible material is graphene.

9. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 1, characterized in that: The bottom end surface of the heat insulation unit is made of rigid material.

10. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 9, characterized in that: The bottom end surface of the thermal insulation unit is made of Corning glass.

11. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 1, characterized in that: The side surfaces and top end surfaces of the heat insulation unit are covered with a heat radiation shielding layer.

12. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 11, characterized in that: The shielding layer is a uniform metal material layer.

13. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 12, characterized in that: The shielding layer is made of aluminum alloy and nickel silver.

14. The special-shaped heat flux deep temperature measurement probe considering contact thermal resistance according to claim 12, characterized in that: The thickness of the shielding layer is controlled to be less than 1 mm.

15. A method for measuring deep temperature using the measuring probe according to any one of claims 1 to 13, characterized in that: Press the bottom of the measuring probe on the skin surface of the part to be measured, obtain the pressing pressure P applied to the measuring probe and the detection data of all temperature sensors and heat flux sensors in the measuring probe, and calculate the deep temperature of the part to be measured : in: is the thermal resistance between the skin and the deep temperature at a specified compression pressure and the thermal contact resistance between the skin and the part to be tested The sum is the pre-calibrated value; is the contact thermal resistance related to the pressing pressure P The change is pre-calibrated The mapping relationship between P and is determined; is the skin surface temperature of the part to be measured; is the ambient temperature of the measuring probe during measurement; m is the ambient temperature The relevant correction coefficient is a pre-calibrated value; is the heat flux value within the heat transfer unit, which is obtained by calibrating the heat flux values ​​detected by all heat flux sensors inside the heat transfer unit. The calibration formula is: , where is the pre-calibrated i-th calibration coefficient, is the heat flux value detected by the i-th heat flux sensor inside the heat transfer unit, is the total number of heat flux sensors inside the heat transfer unit.

Images