阅读说明：本技术 一种热壁热流传感器及其测试方法 (Hot wall heat flow sensor and testing method thereof ) 是由 王辉 朱涛 朱新新 杨凯 杨庆涛 程光辉 于 2021-02-05 设计创作，主要内容包括：本发明公开了一种新颖的热壁热流传感器及其测试方法,包括：基于一维传热假设,构建了一种可承受高温的带封装结构和传热体径向双孔测温的热壁热流传感器。本发明的热壁热流传感器结构和材料选择可以实现较长时间低频动态中低热流测试,可以应用于气动热与热防护地面与飞行测试试验模型表面微扰动动态热流测试环境中。(The invention discloses a novel hot wall heat flow sensor and a test method thereof, wherein the novel hot wall heat flow sensor comprises the following steps: based on the assumption of one-dimensional heat transfer, a hot wall heat flow sensor which can bear high temperature and has a packaging structure and a heat transfer body for radial double-hole temperature measurement is constructed. The structure and material selection of the hot wall heat flow sensor can realize long-time low-frequency dynamic low-heat flow test, and can be applied to the test environment of aerodynamic heat and thermal protection ground and surface perturbation dynamic heat flow of a flight test model.)

1. A hot wall heat flow sensor and a test method thereof are characterized by comprising the following steps:

a housing having a T-shaped cavity therein; two layers of ceramic gaskets are arranged at the rear part of the T-shaped cavity;

the heat transfer body is provided with a radial through hole I and a radial through hole II which are mutually crossed at a certain interval at the front part, and the front end port is in flush transition fit with the front end of the shell; the rear part of the heat transfer body is fixed between the two layers of ceramic gaskets through an integrally formed flange plate, and a threaded column is arranged on a rear port; two layers of ceramic penetrating pieces and insulating sleeves are sleeved on the threaded columns and are screwed and fixed through fixing nuts; a pair of stepped holes I and a pair of stepped holes II which are big in top and small in bottom and cross with each other are arranged on the two layers of ceramic through pieces; a pair of corundum tubes I and a pair of corundum tubes II corresponding to the radial through holes I and the radial through holes II are embedded in the side face of the heat transfer body; the rear ends of the pair of corundum tubes I and the pair of corundum tubes II are respectively embedded into the pair of stepped holes I and the pair of stepped holes II;

the temperature measuring node I in the middle of the butt-joint type thermocouple wire I is tightly attached to the middle of the radial through hole I, and a pair of small glass fiber tubes I are sleeved on the two ends of the butt-joint type thermocouple wire I after penetrating out of the pair of stepped holes I and are wrapped in the large glass fiber tubes;

the temperature measuring node II in the middle of the butt-joint thermocouple wire II is tightly attached to the middle of the radial through hole II, and a pair of small glass fiber tubes II are sleeved on the two ends of the butt-joint thermocouple wire II after penetrating out of the pair of stepped holes II and are wrapped in the large glass fiber tubes;

the tail clamp is detachably connected with the rear end of the shell; the tail clamp is provided with a tail frame pressing sheet; the tail frame pressing sheet is positioned on one side of the large glass fiber tube and is pressed and fixed through two fixing bolts.

2. The thermal wall flow sensor of claim 1, wherein said housing and said heat transfer body are the same superalloy material.

3. The hot wall heat flow sensor of claim 1, wherein two layers of the ceramic spacer and two layers of the ceramic lead-through are made of zirconia.

4. The hot wall heat flow sensor of claim 1, wherein the housing is a T-shaped cylindrical structure; the front part of the shell is provided with a thin external thread of M8x0.75 with the length of 10mm, and the length of the front port is 1.5mm, and the diameter is 6.5 mm.

5. The hot wall heat flow sensor of claim 1, wherein an air gap exists between the T-cavity and the heat transfer body; an annular knife edge hole with a small upper part and a big lower part is arranged on a port at the front part of the shell; the smaller end of the annular blade hole is in flush and tight fit with the front end of the heat transfer body, and the larger end of the annular blade hole is communicated with the air gap.

6. The thermal wall flow sensor of claim 1, wherein said heat transfer body is a variable diameter cylindrical structure with a total length of 29mm from front to back of Φ 4.9mm, Φ 9mm, Φ 4.9mm and Φ 2mm, respectively; the inner diameters of the radial through hole I and the radial through hole II are phi 0.2 mm.

7. The hot wall heat flow sensor of claim 1, wherein a pair of said corundum tubes i and ii have an outer diameter of Φ 0.9mm, an inner diameter of Φ 0.4mm, and lengths of 22.8mm and 20.8mm, respectively; and the distance between the front end of the radial through hole I and the center line of the radial through hole II is 0.3 mm.

8. The hot wall heat flow sensor of claim 1, wherein the retaining nut is an M2 ceramic hexagonal nut.

9. The hot wall heat flow sensor of claim 1, wherein the housing rear end is provided with an M12 internally threaded tube; the front end of the tail clamp is provided with an M12 external thread pipe; the rear end of the T-shaped cavity is sealed and the two layers of ceramic gaskets are compressed through the threaded connection of the external threaded pipe and the internal threaded pipe, so that the stable connection of all parts is ensured, and the detachable connection is realized; two compression screw holes I of M2 are formed in two sides of the internal threaded pipe; two M2 hexagon socket flat-end set screws are respectively in threaded connection with the two M2 compression screw holes I, so that the external thread pipe is compressed and fixed from two sides.

10. The hot wall heat flow sensor of claim 1, wherein two M2 hold-down screw holes ii are provided on both sides of the tail clamp tab; the two fixing bolts are two M2 socket head cap screws; and the two fixing bolts are respectively in threaded connection with the two pressing screw holes II, so that the large glass fiber tube is pressed on the tail clamp pressing sheet.

11. A method for performing a hot wall heat flow test using the hot wall heat flow sensor according to any one of claims 1 to 10, comprising the steps of:

step one, calibrating the square wave heat flow amplitude of a heat flow sensor calibration test platform: the heat flow sensor calibration experiment platform provides square-waveform input heat flow; then, a reference heat flow sensor is used for testing the absolute heat flow q of the amplitude of the square wave heat flow_cAnd testing the absolute heat flow q_cThe amplitude of the square wave heat flow is used as the calibration input of the hot wall heat flow sensor based on the assumption of the one-dimensional nonlinear heat transfer body;

step two, synchronously acquiring a spectral path photodiode signal s (k) of square waveform input heat flow with the amplitude value calibrated by taking the sampling time interval as delta T and temperature data T of a temperature measurement node I and a temperature measurement node II of a hot wall heat flow sensor based on the assumption of a one-dimensional nonlinear heat transfer body₁(k)、T₂(k) (ii) a Normalizing the s (k) signal to reflect the nominal heat flow waveform, and combining the signal with the known nominal input square wave heat flow amplitude q_cThe dynamic calibration input heat flow q (k) of the heat flow sensor based on the assumption of the one-dimensional nonlinear heat transfer body can be obtained;

step three, adopting a Levenberg-Marquardt optimization identification algorithm, and combining the dynamic calibration input heat flow q (k) and the temperature data T of the heat flow sensor based on the assumption of the one-dimensional nonlinear heat transfer body₁(k) And T₂(k) According to the optimal objective functionNonlinear artificial neural network model for adjusting number of neurons in single hidden layer to be 3Parameter vector ofI.e. weight coefficients and threshold values, such that the heat flow is estimatedWith actual calibration of the input heat flow q_incident(k) The mean square error is minimum, thereby obtaining the optimal parameter vectorK is the number of parameters of the nonlinear artificial neural network model; gamma-shaped_KIs K-dimensional vector space; n is the logarithm of calibration test data; q. q.s_incident(k) To calibrate the input heat flow; in addition, the first and second substrates are,

the total number of the input variables of the nonlinear artificial neural network is 10.

Step four, obtaining a heat inverse estimation model of the heat flow sensor based on the assumption of the one-dimensional nonlinear heat transfer body according to the optimal parameter vector obtained in the step three, namely

Wherein the content of the first and second substances,estimating the dynamic heat flow for the inverse;and optimizing the parameter vector for the nonlinear neural network model.

Technical Field

The invention relates to the technical field of ground heat protection tests and flight test tests of hypersonic devices, in particular to a hot wall heat flow sensor based on one-dimensional nonlinear heat transfer and a test method thereof.

Background

In the test of the aerodynamic heat and the thermal protection, the effective acquisition of the heat flow data plays an important role in improving the thermal response prediction model of the aerodynamic heat environment and the thermal protection material thereof. Cold wall heat flow testing methods, including plug, zero, water card and gordon have found wide application in aerodynamic heat and thermal protection tests.

However, in the long-time pneumatic heating process, because the cold wall heat flow sensor is inconsistent with the surrounding model in terms of material and surface temperature, obvious differences exist in the heat exchange processes such as catalytic heat effect, heat transfer characteristics of a convection boundary layer, heat dissipation of convection heat and heat radiation, and the like, so that the cold wall heat flow measurement cannot completely and truly reflect the surface heat flow of the heat-proof model in the hypersonic aircraft flight environment/ground simulation test. In addition, in the ground or flight test environment of aerodynamic heat and thermal protection, the surface of the model has a non-one-dimensional heat transfer phenomenon, so that the accuracy of heat flow test or inverse identification is low.

Disclosure of Invention

An object of the present invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages described hereinafter.

To achieve these objects and other advantages in accordance with the purpose of the invention, there is provided a hot wall heat flow sensor and a method for testing the same, including: a housing having a T-shaped cavity therein; two layers of ceramic gaskets are arranged at the rear part of the T-shaped cavity;

the heat transfer body is provided with a radial through hole I and a radial through hole II which are mutually crossed at a certain interval at the front part, and the front end port is in flush transition fit with the front end of the shell; the rear part of the heat transfer body is fixed between the two layers of ceramic gaskets through an integrally formed flange plate, and a threaded column is arranged on a rear port; two layers of ceramic penetrating pieces and insulating sleeves are sleeved on the threaded columns and are screwed and fixed through fixing nuts; a pair of stepped holes I and a pair of stepped holes II which are big in top and small in bottom and cross with each other are arranged on the two layers of ceramic through pieces; a pair of corundum tubes I and a pair of corundum tubes II corresponding to the radial through holes I and the radial through holes II are embedded in the side face of the heat transfer body; the rear ends of the pair of corundum tubes I and the pair of corundum tubes II are respectively embedded into the pair of stepped holes I and the pair of stepped holes II; the temperature measuring node I in the middle of the butt-joint type thermocouple wire I is tightly attached to the middle of the radial through hole I, and a pair of small glass fiber tubes I are sleeved on the two ends of the butt-joint type thermocouple wire I after penetrating out of the pair of stepped holes I and are wrapped in the large glass fiber tubes; the temperature measuring node II in the middle of the butt-joint thermocouple wire II is tightly attached to the middle of the radial through hole II, and a pair of small glass fiber tubes II are sleeved on the two ends of the butt-joint thermocouple wire II after penetrating out of the pair of stepped holes II and are wrapped in the large glass fiber tubes; the tail clamp is detachably connected with the rear end of the shell; the tail clamp is provided with a tail frame pressing sheet; the tail frame pressing sheet is positioned on one side of the large glass fiber tube and is pressed and fixed through two fixing bolts.

Preferably, the casing and the heat transfer body are made of the same high-temperature alloy material.

Preferably, the two ceramic gaskets and the two ceramic sheets are made of zirconia.

Preferably, the housing is a T-shaped cylinder structure. The front part of the shell is provided with a thin external thread of M8x0.75 with the length of 10mm, and the length of the front port is 1.5mm, and the diameter is 6.5 mm.

Preferably, an air gap exists between the T-shaped cavity and the heat transfer body; an annular knife edge hole with a small upper part and a big lower part is arranged on a port at the front part of the shell; the smaller end of the annular blade hole is in flush and tight fit with the front end of the heat transfer body, and the larger end of the annular blade hole is communicated with the air gap.

Preferably, the heat transfer body is a variable-diameter cylindrical structure, and the total length of the heat transfer body is 29mm, wherein the diameter of the heat transfer body is phi 4.9mm, phi 9mm, phi 4.9mm and phi 2mm from the front end to the rear end; the inner diameters of the radial through hole I and the radial through hole II are phi 0.2 mm.

Preferably, the pair of corundum tubes I and the pair of corundum tubes II have the outer diameter of phi 0.9mm, the inner diameter of phi 0.4mm and the lengths of 22.8mm and 20.8mm respectively; and the distance between the front end of the radial through hole I and the center line of the radial through hole II is 0.3 mm.

Preferably, wherein the fixing nut is an M2 ceramic hexagonal nut.

Preferably, wherein the rear end of the shell is provided with an M12 internal thread tube; the front end of the tail frame is provided with an M12 external thread pipe; the rear end of the T-shaped cavity is sealed and the two layers of ceramic gaskets are compressed through the threaded connection of the external threaded pipe and the internal threaded pipe, so that the stable connection of all parts is ensured, and the detachable connection is realized; two compression screw holes I of M2 are formed in two sides of the internal threaded pipe; two M2 hexagon socket flat-end set screws are respectively in threaded connection with the two M2 compression screw holes I, so that the external thread pipe is compressed and fixed from two sides.

Preferably, two compression screw holes II of M2 are arranged on two sides of the tail clamping and pressing sheet; the two fixing bolts are two M2 socket head cap screws; and the two fixing bolts are respectively in threaded connection with the two pressing screw holes II, so that the large glass fiber tube is pressed on the tail clamp pressing sheet.

The invention also provides a method for carrying out hot wall heat flow test by adopting the hot wall heat flow sensor, which comprises the following steps:

step one, calibrating the square wave heat flow amplitude of a heat flow sensor calibration test platform: the heat flow sensor calibration experiment platform provides square-waveform input heat flow; then, a reference heat flow sensor is used for testing the absolute heat flow q of the amplitude of the square wave heat flow_cAnd testing the absolute heat flow q_cAs a hot-wall heat-flow sensor based on the assumption of a one-dimensional nonlinear heat-transfer bodyCalibrating the amplitude of the heat flow of the input square wave;

step two, synchronously acquiring a spectral path photodiode signal s (k) of square waveform input heat flow with the amplitude value calibrated by taking the sampling time interval as delta T and temperature data T of a temperature measurement node I and a temperature measurement node II of a hot wall heat flow sensor based on the assumption of a one-dimensional nonlinear heat transfer body₁(k)、T₂(k) (ii) a Normalizing the s (k) signal to reflect the nominal heat flow waveform, and combining the signal with the known nominal input square wave heat flow amplitude q_cThe dynamic calibration input heat flow q (k) of the heat flow sensor based on the assumption of the one-dimensional nonlinear heat transfer body can be obtained;

step three, adopting a Levenberg-Marquardt optimization identification algorithm, and combining the dynamic calibration input heat flow q (k) and the temperature data T of the heat flow sensor based on the assumption of the one-dimensional nonlinear heat transfer body₁(k) And T₂(k) According to the optimal objective functionNonlinear artificial neural network model for adjusting number of neurons in single hidden layer to be 3Parameter vector ofI.e. weight coefficients and threshold values, such that the heat flow is estimatedWith actual calibration of the input heat flow q_incident(k) The mean square error is minimum, thereby obtaining the optimal parameter vectorK is the number of parameters of the nonlinear artificial neural network model; gamma-shaped_KIs K-dimensional vector space; n is the logarithm of calibration test data; q. q.s_incident(k) To calibrate the input heat flow; in addition, the first and second substrates are,

the total number of the input variables of the nonlinear artificial neural network is 10.

Step four, obtaining a heat inverse estimation model of the heat flow sensor based on the assumption of the one-dimensional nonlinear heat transfer body according to the optimal parameter vector obtained in the step three, namely

Wherein the content of the first and second substances,estimating the dynamic heat flow for the inverse;and optimizing the parameter vector for the nonlinear neural network model.

The invention at least comprises the following beneficial effects:

the invention constructs a hot wall heat flow sensor with a packaging structure and a heat transfer body radial double-hole temperature measurement capable of bearing high temperature based on a one-dimensional heat transfer hypothesis, can realize a long-time low-frequency dynamic low-heat flow test, and can be applied to a micro-disturbance dynamic heat flow test environment on the surface of a pneumatic heat and thermal protection ground and a flight test model.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Description of the drawings:

FIG. 1 is a front sectional view of a hot wall heat flow sensor provided by the present invention;

FIG. 2 is a left side sectional view of a hot wall heat flow sensor provided by the present invention;

FIG. 3 is a bottom sectional view of a hot wall heat flow sensor provided by the present invention;

FIG. 4 is a top view of a hot wall heat flow sensor provided by the present invention;

the specific implementation mode is as follows:

the present invention is further described in detail below with reference to the attached drawings so that those skilled in the art can implement the invention by referring to the description text.

It will be understood that terms such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof.

It is to be understood that in the description of the present invention, the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are used only for convenience in describing the present invention and for simplification of the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, unless otherwise specifically stated or limited, the terms "mounted," "disposed," "sleeved/connected," "connected," and the like are used broadly, and for example, "connected" may be a fixed connection, a detachable connection, or an integral connection, a mechanical connection, an electrical connection, a direct connection, an indirect connection via an intermediate medium, or a communication between two elements, and those skilled in the art will understand the specific meaning of the terms in the present invention specifically.

Further, in the present invention, unless otherwise explicitly specified or limited, a first feature "on" or "under" a second feature may be directly contacted with the first and second features, or indirectly contacted with the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature.

Fig. 1-4 show an implementation form of the present invention, comprising:

a housing 1 having a T-shaped cavity 11 therein; two layers of ceramic gaskets 12 are arranged at the rear part of the T-shaped cavity 11;

the heat transfer body 2 is provided with two radial through holes I21 and two radial through holes II 22 which are mutually crossed at a certain interval at the front part, and the front end port is in flush transition fit with the front end of the shell 1; the rear part of the heat transfer body 2 is fixed between the two layers of the ceramic gaskets 12 through an integrally formed flange 23, and a threaded column 24 is arranged on the port of the rear part; two layers of ceramic penetrating sheets 25 and insulating sleeves 26 are sleeved on the threaded columns 24 and are screwed and fixed through fixing nuts 27; a pair of stepped holes I251 and a pair of stepped holes II 252 which are big in top and small in bottom and cross with each other are arranged on the two layers of ceramic threading sheets 25; a pair of corundum tubes I28 and a pair of corundum tubes II 29 corresponding to the radial through holes I21 and the radial through holes II 22 are embedded in the side face of the heat transfer body 2; the rear ends of the pair of corundum tubes I28 and the pair of corundum tubes II 29 are respectively embedded into the pair of stepped holes 251I and the pair of stepped holes II 252;

the temperature measuring node I31 in the middle of the butt-joint type thermocouple wire I3 is tightly attached to the middle of the radial through hole I21, and two ends of the butt-joint type thermocouple wire I3 penetrate out of the pair of stepped holes I251 and then are sleeved with the pair of small glass fiber tubes I32 and wrapped in the large glass fiber tube 5;

the middle temperature measuring node II 41 of the butt-joint thermocouple wire II 4 is tightly attached to the middle of the radial through hole II 22, and two ends of the butt-joint thermocouple wire II penetrate through the pair of stepped holes II 252 and then are sleeved with the pair of small glass fiber tubes II 42 and wrapped in the large glass fiber tube 5;

the tail clamp 6 is detachably connected with the rear end of the shell 1; a tail frame pressing sheet 61 is arranged on the tail clamp 6; the tailstock pressing sheet 61 is positioned on one side of the large glass fiber pipe 5 and is pressed and fixed through two fixing bolts 62.

The working principle is as follows:

in the surface micro-disturbance hot wall heat flow test of a pneumatic thermal environment model of a hypersonic ground/flight test, after the front end of a shell 1 and the front end of a heat transfer body 2 are contacted with input heat flow, a temperature measurement node I31 on a butt-joint type thermocouple wire I3 in the middle of a radial through hole I21 and a temperature measurement node II 41 on a butt-joint type thermocouple wire II 4 in the middle of a radial through hole II 22 respectively obtain temperature data T₁(k) And T₂(k) (ii) a Of butt-joint type thermocouple wire I3 and butt-joint type thermocouple wire II 4Two ends of the shell respectively penetrate out of the pair of stepped holes I251 and the pair of stepped holes II 252 and then are sleeved with the pair of small glass fiber tubes I32 and the pair of small glass fiber tubes II 44, and then the two ends of the shell are all input into corresponding detection instruments through the plurality of externally connected leads 7 to be tested and calculated, so that the input heat flow q at the front end of the shell 1 can be obtained_e(k) In that respect In the technical scheme, the temperature measurement node I31 and the temperature measurement node II 41 realize one-dimensional heat transfer, simplify heat transfer boundary conditions and improve measurement accuracy; the radial through hole I21 and the radial through hole II 21 have certain distance and are cross-shaped with each other, so that the temperature measurement precision of an isothermal layer is ensured, and simultaneously, the embedded installation of a pair of corundum tubes I28 and a pair of corundum tubes II 29 on the side surface of the heat transfer body 2 is facilitated; the pair of corundum tubes I28 and the pair of corundum tubes II 29 ensure high-temperature-resistant insulativity of the butt-joint type thermocouple wire I3 and the butt-joint type thermocouple wire II 4 at other parts except the radial through hole I21 and the radial through hole II 22; the pair of stepped holes I251 and the pair of stepped holes II 252 ensure the stable limit of the rear ends of the pair of corundum tubes I28 and the pair of corundum tubes II 29; the two layers of ceramic gaskets 12 can obstruct the heat transfer influence between the shell 1 and the heat transfer body 2 as much as possible; the pair of small glass fiber tubes I32, the pair of small glass fiber tubes II 42 and the large glass fiber tube 5 protect the high-temperature insulation between the butt-joint type thermocouple wire I3 and the butt-joint type thermocouple wire II 4 which penetrate out of the two layers of ceramic through pieces 25, and meanwhile, the electric contact between the butt-joint type thermocouple wire I3 and the butt-joint type thermocouple wire II 4 is avoided; the tail clamping and pressing sheet 61 can compress the large glass fiber tube 5, so that a plurality of wires 7 of the external detection instrument at the rear end of the shell 1 are prevented from loosening and the risk of pulling and breaking is reduced.

In the above technical solution, the casing 1 and the heat transfer body 2 are made of the same high temperature alloy material. The arrangement can reduce the temperature difference between the shell 1 and the heat transfer body 2, reduce the lateral heat transfer and improve the one-dimensional heat transfer hypothesis approximation precision.

In the above technical solution, the two layers of the ceramic gasket 12 and the two layers of the ceramic penetration pieces 25 are made of zirconia. This arrangement ensures high temperature resistance and heat insulation at the joint of the respective parts of the heat transfer body 2, preventing electrical contact.

In the above technical solution, the housing 1 is a T-shaped cylindrical structure. The front of the housing 1 is provided with a 10mm long, m8x0.75, thin external thread 101, and the front port 102 is 1.5mm long and 6.5mm in diameter. This arrangement provides a better enclosure and insulation for the housing 1, while providing space for other components inside and outside the housing 1.

In the above technical solution, an air gap 103 exists between the T-shaped cavity 11 and the heat transfer body 2; an annular blade hole 104 with a small upper part and a big lower part is arranged on a port at the front part of the shell 1; the smaller end of the annular blade hole 104 is flush and tightly fitted with the front end of the heat transfer body 2, and the larger end is communicated with the air gap 103. The circumferential contact area between the front end of the heat transfer body 2 and the front end of the shell 1 can be reduced through the annular blade hole 104 with a small upper part and a large lower part, heat insulation is carried out, and meanwhile, the heat insulation effect is further improved by matching with the air gap 103, and the approximate precision of one-dimensional heat transfer is ensured.

In the above technical solution, the heat transfer body 2 is a variable diameter cylindrical structure, and has a total length of 29mm, and the diameter is phi 4.9mm, phi 9mm, phi 4.9mm and phi 2mm from the front end to the rear end; the inner diameters of the radial through hole I251 and the radial through hole II 252 are phi 0.2 mm. The heat conduction effect can be improved by the arrangement, and the test response speed of the hot wall heat flow sensor is improved.

In the technical scheme, the pair of corundum tubes I28 and the pair of corundum tubes II 29 have the outer diameter of phi 0.9mm, the inner diameter of phi 0.4mm and the lengths of 22.8mm and 20.8mm respectively; and the distance between the front end of the connecting rod and the center line of the radial through hole I21 and the center line of the radial through hole II 22 is 0.3 mm. The arrangement makes the penetration installation of the butt-joint thermocouple wire I3 and the butt-joint thermocouple wire II 4 between the pair of corundum tubes I28 and the pair of corundum tubes II 29 more convenient.

In the above technical solution, the fixing nut 27 is an M2 ceramic hexagonal nut. The arrangement can ensure the high temperature resistance and heat insulation of the bottom of the heat transfer body 2 and prevent electrical contact;

in the above technical solution, the rear end of the housing 1 is provided with an M12 internal threaded tube 105; the front end of the tailstock 6 is provided with an M12 external thread pipe 106; the threaded connection between the external threaded pipe 106 and the internal threaded pipe 102 realizes the sealing of the rear end of the T-shaped cavity 11 and the compression of the two layers of ceramic gaskets 12, ensures the stable connection of all parts and realizes the detachable connection; two compression screw holes I107 of M2 are formed in two sides of the internal threaded pipe 105; the two M2 hexagon socket flat-end set screws 108 are respectively in threaded connection with the two M2 compression screw holes I107, so that the external thread pipe 106 is compressed and fixed from two sides. The arrangement can ensure that the tail clamp 6 is more stably connected with the shell 1, is convenient to mount and dismount, and can avoid the looseness of the external thread pipe 106 screwed together due to vibration.

In the technical scheme, two compression screw holes II 108 of M2 are arranged on two sides of the tail clamping and pressing sheet 61; the two fixing bolts 62 are two M2 socket head cap screws; the large glass fiber tube 5 is tightly pressed on the tail clamping and pressing sheet 61 by using two fixing bolts 62 which are respectively in threaded connection with two pressing screw holes II 108. The arrangement can ensure that the tail clamping and pressing sheet 61 has better pressing effect on the large glass fiber tube 5 and can prevent looseness.

A method for carrying out hot wall heat flow test by adopting the hot wall heat flow sensor comprises the following steps:

step one, calibrating the square wave heat flow amplitude of a heat flow sensor calibration test platform: the heat flow sensor calibration experiment platform provides square-waveform input heat flow; then, a reference heat flow sensor is used for testing the absolute heat flow q of the amplitude of the square wave heat flow_cAnd testing the absolute heat flow q_cThe amplitude of the square wave heat flow is used as the calibration input of the hot wall heat flow sensor based on the assumption of the one-dimensional nonlinear heat transfer body;

step two, synchronously acquiring a spectral path photodiode signal s (k) of square waveform input heat flow with the amplitude value calibrated by taking the sampling time interval as delta T and temperature data T of a temperature measurement node I31 and a temperature measurement node II 41 of a hot wall heat flow sensor based on the assumption of a one-dimensional nonlinear heat transfer body₁(k)、T₂(k) (ii) a Normalizing the s (k) signal to reflect the nominal heat flow waveform, and combining the signal with the known nominal input square wave heat flow amplitude q_cThe dynamic calibration input heat flow q (k) of the heat flow sensor based on the assumption of the one-dimensional nonlinear heat transfer body can be obtained;

step three, adopting LevenbergMarquardt optimal identification algorithm combined with dynamic calibration of input heat flow q (k) and temperature data T of a heat flow sensor based on one-dimensional nonlinear heat transfer body assumptions₁(k) And T₂(k) According to the optimal objective functionNonlinear artificial neural network model for adjusting number of neurons in single hidden layer to be 3Parameter vector ofI.e. weight coefficients and threshold values, such that the heat flow is estimatedWith actual calibration of the input heat flow q_incident(k) The mean square error is minimum, thereby obtaining the optimal parameter vectorK is the number of parameters of the nonlinear artificial neural network model; gamma-shaped_KIs K-dimensional vector space; n is the logarithm of calibration test data; q. q.s_incident(k) To calibrate the input heat flow; in addition, the first and second substrates are,

the total number of the input variables of the nonlinear artificial neural network is 10.

Step four, obtaining a heat inverse estimation model of the heat flow sensor based on the assumption of the one-dimensional nonlinear heat transfer body according to the optimal parameter vector obtained in the step three, namely

Wherein the content of the first and second substances,estimating the dynamic heat flow for the inverse;and optimizing the parameter vector for the nonlinear neural network model.

The number of apparatuses and the scale of the process described herein are intended to simplify the description of the present invention. Applications, modifications and variations of the present invention will be apparent to those skilled in the art.

While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable in various fields of endeavor to which the invention pertains, and further modifications may readily be made by those skilled in the art, it being understood that the invention is not limited to the details shown and described herein without departing from the general concept defined by the appended claims and their equivalents.