阅读说明：本技术 高热流耦合环境下双探头热流计及其热流密度的测定方法 (Double-probe heat flow meter in high heat flow coupling environment and method for measuring heat flow density thereof ) 是由 董士奎 孙一强 贺志宏 帅永 李嘉宁 于 2018-08-16 设计创作，主要内容包括：一种高热流耦合环境下双探头热流计及其热流密度的测定方法,涉及热流测量技术领域。本发明解决了现有的热流计均无法同时测量对流热、纯辐射热流和总热流值的问题。它包括相邻设置在燃烧室内的两个探头,每个探头均包括第一冷套组件、第二冷套组件、紫铜芯体以及两根热电偶,所述第一冷套组件包括外壳、内套、第一进水管、第一出水管、分区隔板和若干折流板,外壳为桶状结构且外壳的桶底部开设有直通孔,内套包括由上到下依次同轴固接为一体且呈阶梯状分布的第一至第四圆柱段,且内套沿其中心轴向位置开设有阶梯通孔,外壳扣装在第四圆柱段上方,第一圆柱段穿装在直通孔内且第一圆柱段的顶面与外壳的桶底面位于同一水平面。(A double-probe heat flow meter under a high heat flow coupling environment and a method for measuring heat flow density thereof relate to the technical field of heat flow measurement. The invention solves the problem that the existing heat flow meters can not measure the convection heat, the pure radiation heat flow and the total heat flow value simultaneously. The device comprises two probes adjacently arranged in a combustion chamber, wherein each probe comprises a first cold sleeve assembly, a second cold sleeve assembly, a red copper core body and two thermocouples, the first cold sleeve assembly comprises a shell, an inner sleeve, a first water inlet pipe, a first water outlet pipe, a partition plate and a plurality of baffle plates, the shell is of a barrel-shaped structure, a through hole is formed in the barrel bottom of the shell, the inner sleeve comprises first to fourth cylindrical sections which are sequentially coaxially and fixedly connected into a whole from top to bottom and distributed in a step shape, the inner sleeve is provided with a step through hole along the central axial position of the inner sleeve, the shell is buckled above the fourth cylindrical section, the first cylindrical section is arranged in the through hole in a penetrating mode, and the top surface of the first cylindrical section and the barrel bottom surface of the shell are located on the same horizontal plane.)

1. A double-probe heat flow meter under high heat flow coupling environment is characterized in that: it comprises two probes adjacently arranged in a combustion chamber, each probe comprises a first cold sleeve component (1-1), a second cold sleeve component (1-2), a red copper core body (1-3) and two thermocouples (1-4),

the first cold sleeve component (1-1) comprises a shell (1-11), an inner sleeve (1-12), a first water inlet pipe (1-13), a first water outlet pipe (1-14), partition plates (1-15) and a plurality of baffle plates (1-16), wherein the shell (1-11) is of a barrel-shaped structure, a through hole (1-111) is formed in the barrel bottom of the shell (1-11), the inner sleeve (1-12) comprises first to fourth cylindrical sections which are sequentially and coaxially fixedly connected into a whole from top to bottom and distributed in a step shape, a step through hole (1-125) is formed in the inner sleeve (1-12) along the central axial position of the inner sleeve, the shell (1-11) is buckled above the fourth cylindrical section (1-124), and the shell (1-11) is in threaded connection with the third cylindrical section (1-123), the first cylindrical section (1-121) is arranged in the through hole (1-111) in a penetrating way, the top surface of the first cylindrical section (1-121) and the barrel bottom surface of the shell (1-11) are positioned on the same horizontal plane, the partition plates (1-15) and the baffle plates (1-16) are vertically welded on the outer walls of the second cylindrical section (1-122) and are in gapless contact with the inner wall of the shell (1-11), gaps are reserved between the adjacent partition plates (1-15) and the baffle plates (1-16) and between the adjacent two baffle plates (1-16), the top ends of the partition plates (1-15) are in gapless contact with the barrel bottom of the shell (1-11), the bottom ends of the partition plates (1-15) are in gapless contact with the top ends of the third cylindrical section (1-123), and the baffle plates (1-16) are arranged in a staggered way, the first water inlet pipes (1-13) and the first water outlet pipes (1-14) are respectively vertically penetrated and welded on the inner sleeves (1-12) at the two sides of the partition boards (1-15),

the second cold sleeve component (1-2) comprises cold sleeves (1-21), end covers (1-22), second water inlet pipes (1-23) and second water outlet pipes (1-24), the upper parts of the cold sleeves (1-21) are positioned inside the inner sleeves (1-12) and are in threaded connection with the inner sleeves (1-12), the end covers (1-22) are in threaded connection with the lower parts of the cold sleeves (1-21), the second water inlet pipes (1-23) and the second water outlet pipes (1-24) are vertically penetrated and welded on the end covers (1-22), the top ends of the second water inlet pipes (1-23) are arranged close to the red copper core bodies (1-3), the top ends of the second water outlet pipes (1-24) and the top surfaces of the end covers (1-22) are positioned on the same horizontal plane,

the red copper core body (1-3) is arranged in the inner sleeve (1-12) in a penetrating way, the top surface of the red copper core body (1-3) and the barrel bottom surface of the outer shell (1-11) are positioned on the same horizontal plane, the lower part of the red copper core body (1-3) is arranged at the upper part of the cold sleeve (1-21) in a penetrating way and is connected with the cold sleeve (1-21) in a threaded way,

two blind holes (1-31) are formed in the side wall of the middle of the red copper core body (1-3) from top to bottom, two thermocouples (1-4) are arranged on the end covers (1-22) in a penetrating mode, measuring ends of the two thermocouples (1-4) are correspondingly inserted into the two blind holes (1-31), and a heat absorbing layer is sprayed on the top surface of the red copper core body (1-3) in one probe.

2. A dual probe heat flow meter in a high heat flow coupled environment according to claim 1 wherein: and heat insulation materials are filled between the red copper core body (1-3) and the inner sleeve (1-12).

3. A dual probe heat flow meter in a high heat flow coupled environment according to claim 1 or 2, wherein: the red copper core body (1-3) is a three-section variable cross-section coaxial cylinder and comprises an induction section (1-32), a measurement section (1-33) and a cooling section (1-34) which are coaxially and fixedly connected from top to bottom, the red copper core body (1-3) is arranged inside the inner sleeve (1-12) in a penetrating way, the top end surfaces of the induction sections (1-32) and the bottom surfaces of the shells (1-11) are located on the same horizontal plane, the lower parts of the cooling sections (1-34) are arranged on the upper parts of the cooling sleeves (1-21) in a penetrating mode and are in threaded connection with the cooling sleeves (1-21), the two thermocouples (1-4) are sequentially arranged on the end covers (1-22) and the cooling sections (1-34) in a penetrating mode from bottom to top, and the measuring ends of the two thermocouples (1-4) are inserted into the measuring sections (1-33).

4. A dual probe heat flow meter in a high heat flow coupled environment according to claim 3 wherein: the diameter phi 'of the measuring section (1-33) of the red copper core body (1-3) is smaller than the diameter phi' of the induction section (1-32).

5. A dual probe heat flow meter in a high heat flow coupled environment according to claim 3 wherein: the distance between the two blind holes (1-31) on the measuring section (1-33) is 6 mm.

6. A dual probe heat flow meter in a high heat flow coupled environment according to claim 4 or 5 wherein: the measuring ends of the thermocouples (1-4) are fixed in the blind holes (1-31) through repair glue, and waterproof resin glue is filled between the thermocouples (1-4) and the cooling sections (1-34) and between the thermocouples (1-4) and the end covers (1-22).

7. A dual probe heat flow meter in a high heat flow coupled environment according to claim 1, 2, 4 or 5 wherein: the plurality of baffle plates (1-16) comprise a plurality of upper baffle plates (1-161) and a plurality of lower baffle plates (1-162) which are arranged in a staggered manner, wherein the top ends of the upper baffle plates (1-161) are in gapless contact with the bottom of the shell (1-11), a gap is formed between the bottom ends of the upper baffle plates (1-161) and the top ends of the third cylindrical sections (1-123), a gap is formed between the top ends of the lower baffle plates (1-162) and the bottom of the shell (1-11), and the bottom ends of the lower baffle plates (1-162) are in gapless contact with the top ends of the third cylindrical sections (1-123).

8. A dual probe heat flow meter in a high heat flow coupled environment according to claim 7 wherein: the lower parts of the outer shells (1-11) and the inner sleeves (1-12) and the lower parts of the cold sleeves (1-21) and the end covers (1-22) are sealed by waterproof resin adhesives.

9. The method for measuring the heat flow density of the double-probe heat flow meter in the high heat flow coupling environment according to any one of claims 1 to 8 is characterized in that: the surface emissivity of the red copper core body (1-3) is calibrated in advance by using a black body furnace, and then the two probes are calibrated to obtain a calibration curve between the temperature difference and the radiant heat flow. When the measuring device is used for measuring a certain environment, the circulating cooler is firstly opened to enable the initial temperatures of the two measuring heads to be consistent, the two measuring heads are the top surfaces of the red copper core bodies (1-3), after heat flow is received, the top surfaces of the red copper core body induction sections (1-32) can absorb heat, and the measuring sections (1-33) are insulated around, so that the measuring sections are simplified into axial one-dimensional heat conduction and are used for measuring the axial temperature difference delta T of the red copper core bodies (1-3) in the two measuring heads₁And Δ T₂The probe for spraying the heat absorbing layer on the top surface of the red copper core body (1-3) is numbered as 1, wherein the red copper core body (1-3) is defined as a No. 1 red copper core body, the probe for spraying the heat absorbing layer on the top surface of the red copper core body (1-3) is numbered as 2, the red copper core body (1-3) is defined as a No. 2 red copper core body, and the following results are obtained through the Fourier law:

wherein:

λ₁-thermal conductivity of red copper core No. 1 (1-3); lambda [ alpha ]₂-thermal conductivity of red copper core No. 2 (1-3);

a' — the area of the top surface of the red copper core induction section (1-32); a' -the cross-sectional area of the red copper core measuring section (1-33);

ΔT₁-axial temperature difference of red copper core No. 1; delta T₂-axial temperature difference of red copper core No. 2;

delta x is the axial distance between two temperature measuring points on each red copper core body;

q″_total1-total heat flow obtained from the top surface of the induction section of the red copper core No. 1; q ″)_total2Total heat flux density from the top surface of induction section of No. 2 red copper core

The energy balance equation of the top surface of the red copper core body (1-3) is obtained:

wherein:

α₁emissivity of the top surface of induction section of No. 1 red copper core α₂The emissivity of the top surface of the induction section of the No. 2 red copper core body;

q″_rad-pure radiant heat flux density;

q″_conv-pure convection heat flux density;

therefore, the difference between the formula (3) and the formula (4) can be obtained to obtain the pure radiation heat flow density q ″)_rad

The pure convection heat flow density q ″' can be obtained by substituting the formula (5) into the formula (3)_conv

Pure radiation heat flow density q ″)_radAnd convective heat flux density q ″)_convThe sum is the total heat flux density q ″)_total

q″_total＝q″_rad+q″_convEquation (7).

Technical Field

The invention relates to a double-probe heat flow meter in a high heat flow coupling environment and a method for measuring heat flow density thereof, and relates to the technical field of heat flow measurement.

Background

With the push ratio of the aero-engine and the aerodynamic heat of the aircraft being higher and higher, the temperature of the aero-engine and the aerodynamic heat of the aircraft can reach 1400-1600 ℃, the local maximum can reach 3000 ℃, and the surface heat flux density can reach 6MW/m²The highest local heat flow density can be predicted to be 8MW/m²And the measuring environment is severe.

The full space of radiation heat flow in the combustion chambers of the gas turbine and the internal combustion engine can reflect thermal environment parameters such as a fuel combustion heat release process, fuel combustion characteristics, wall heat flow distribution and wall temperature distribution of the combustion chambers and the like. In the field of thermal protection, a protective material is subjected to the test of radiation heat flow and the scouring under strong convection, so that the measurement of pure radiation and pure convection heat flow provides reference for selecting a proper material and designing a reliable thermal protection system. Therefore, the pure convection heat flow, the pure radiation heat flow and the total heat flow value in the high-temperature coupling environment are very important for controlling the heating process, evaluating the performance of equipment materials at high temperature and optimizing the performance and the thermal protection of a combustor in a power system.

Disclosure of Invention

The invention aims to solve the problem that the conventional heat flow meter cannot simultaneously measure convection heat, pure radiation heat flow and total heat flow, and further provides a double-probe heat flow meter in a high heat flow coupling environment and a method for measuring heat flow density of the double-probe heat flow meter.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a double-probe heat flow meter under high heat flow coupling environment comprises two probes adjacently arranged in a combustion chamber, each probe comprises a first cold sleeve component, a second cold sleeve component, a red copper core body and two thermocouples,

the first cold sleeve component comprises an outer shell, an inner sleeve, a first water inlet pipe, a first water outlet pipe, a partition plate and a plurality of baffle plates, wherein the outer shell is of a barrel-shaped structure, a through hole is formed in the barrel bottom of the outer shell, the inner sleeve comprises first to fourth cylindrical sections which are sequentially and coaxially fixedly connected into a whole from top to bottom and distributed in a step shape, a step through hole is formed in the inner sleeve along the central axial position of the inner sleeve, the outer shell is buckled above the fourth cylindrical section, the outer shell is in threaded connection with the third cylindrical section, the first cylindrical section is arranged in the through hole in a penetrating mode, the top surface of the first cylindrical section and the barrel bottom surface of the outer shell are located on the same horizontal plane, the partition plate and the baffle plates are vertically welded on the outer wall of the second cylindrical section and are in gapless contact with the inner wall of the outer shell, gaps exist between the adjacent partition plate and the baffle plates and between the adjacent, the bottom end of the partition plate is in gapless contact with the top end of the third cylindrical section, a plurality of baffle plates are arranged in a staggered way, a first water inlet pipe and a first water outlet pipe are respectively vertically penetrated and welded on the inner sleeves at the two sides of the partition plate,

the second cold sleeve component comprises a cold sleeve, an end cover, a second water inlet pipe and a second water outlet pipe, the upper part of the cold sleeve is positioned in the inner sleeve and is in threaded connection with the inner sleeve, the end cover is in threaded connection with the lower part of the cold sleeve, the second water inlet pipe and the second water outlet pipe are respectively vertically penetrated and welded on the end cover, the top end of the second water inlet pipe is arranged close to the red copper core body, the top end of the second water outlet pipe and the top surface of the end cover are positioned on the same horizontal plane,

the red copper core body is arranged in the inner sleeve in a penetrating way, the top surface of the red copper core body and the bottom surface of the outer shell are positioned on the same horizontal plane, the lower part of the red copper core body is arranged at the upper part of the cold sleeve in a penetrating way and is connected with the cold sleeve through threads,

two blind holes are formed in the side wall of the middle of the red copper core body from top to bottom, the two thermocouples are arranged on the end cover in a penetrating mode, the measuring ends of the two thermocouples are correspondingly inserted into the two blind holes, and a heat absorbing layer is sprayed on the top face of the red copper core body in one probe.

A method for measuring the heat flow density of a double-probe heat flow meter in a high heat flow coupling environment comprises the steps of pre-calibrating the surface emissivity of a red copper core body by using a black body furnace, and then calibrating two probes to obtain a calibration curve between temperature difference and radiation heat flow. When measuring to a certain environment, firstly, the circulating cooler is opened to make the initial temperatures of the top surfaces of the two red copper core bodies consistent, after receiving heat flow, the top surfaces of the induction sections of the red copper core bodies can absorb heat, and the measurement sections are simplified into axial one-dimensional heat conduction due to the heat insulation around the measurement sections and are used for measuring two red copper core bodiesAxial temperature difference delta T of red copper core in probe₁And Δ T₂The probe number with red copper core top surface spraying heat-sink shell is 1, and red copper core wherein is defined as No. 1 red copper core, and red copper core top surface uncoated probe number is 2, and red copper core wherein is defined as No. 2 red copper core, derives through the fourier law:

wherein:

λ₁-thermal conductivity of red copper core No. 1; lambda [ alpha ]₂-thermal conductivity of red copper core No. 2;

a' — area of top surface of red copper core induction section; a' -the cross-sectional area of the red copper core measuring section;

ΔT₁-axial temperature difference of red copper core No. 1; delta T₂-axial temperature difference of red copper core No. 2;

delta x is the axial distance between two temperature measuring points on each red copper core body;

q″_total1-total heat flow obtained from the top surface of the induction section of the red copper core No. 1; q ″)_total2-total heat flux density obtained on top of induction section of red copper core No. 2.

The energy balance equation of the red copper core top surface is obtained:

wherein:

α₁emissivity of the top surface of induction section of No. 1 red copper core α₂Emissivity of top surface of induction section of No. 2 red copper core；

q″_rad-pure radiant heat flux density;

q″_conv-pure convection heat flux density;

therefore, the difference between the formula (3) and the formula (4) can be obtained to obtain the pure radiation heat flow density q ″)_rad

The pure convection heat flow density q ″' can be obtained by substituting the formula (5) into the formula (3)_conv

Pure radiation heat flow density q ″)_radAnd convective heat flux density q ″)_convThe sum is the total heat flux density q ″)_total

q″_total＝q″_rad+q″_convFormula (7)

Compared with the prior art, the invention has the following effects:

the induction section of the red copper core serves as a probe for receiving the radiant heat flow. Two probes are arranged adjacently in this application, think that the convection current heat flow that two gauge heads received is the same promptly, and red copper core body top surface spraying in a probe has the heat-sink shell for the radiation that two gauge heads absorbed is different, and the emissivity on surface is different, produces different temperature gradients. And (4) calibrating the emissivity of the top surface of the red copper core body by using a high-temperature black body furnace. Therefore, the pure convection heat flow, the pure radiation heat flow and the total heat flow value can be measured simultaneously under the high heat flow coupling environment.

The probe in this application can work for a long time steadily under the high heat flow condition, and its measuring error is little, and economic nature is good.

Drawings

FIG. 1 is a schematic perspective view of a probe;

FIG. 2 is a schematic sectional view taken along line A-A of FIG. 1;

FIG. 3 is a schematic cross-sectional view taken along line D-D of FIG. 1;

FIG. 4 is a schematic main sectional view of a red copper core;

FIG. 5 is a schematic view of the arrangement of a partition plate and a plurality of baffles.

Detailed Description