High-frequency composite heat flux detection device suitable for aero-engine combustion chamber

Abstract

The invention relates to the technical field of aero-engines, in particular to a high-frequency composite heat flux detection device suitable for an aero-engine combustion chamber, which comprises a shell of a cylindrical structure, a first window hole and a second window hole are formed in the upper end wall of the shell in a penetrating manner, and a protection window is embedded in an upper end hole opening of the first window hole in a sealing manner; a net radiation heat flux probe is installed in the first window hole, a total heat flux probe is installed in the second window hole, the net radiation heat flux probe comprises a first substrate, an yttrium barium copper oxide sensitive layer and a first heat absorption layer are sequentially fixed to the upper surface of the first substrate in a stacked mode from bottom to top, and the total heat flux probe comprises a second substrate. A thermopile sensitive layer, a thermal resistance layer, a protection layer and a second heat absorption layer are sequentially stacked and fixed on the upper surface of the second substrate from bottom to top. The problems that an existing heat flux detection device is incomplete in measurement, low in measurement precision and low in response speed when applied to the aero-engine combustion chamber are solved, and the device is suitable for thermal protection design of the aero-engine combustion chamber.

Description

Technical Field

[0001] This invention relates to the field of aero-engine technology, specifically a high-frequency composite heat flux detection device suitable for aero-engine combustion chambers. Background Technology

[0002] In the thermal protection design of aero-engine combustors, measuring the heat flux within the combustor using a heat flux detection device is a crucial step in assessing the heat load and optimizing the protection scheme. However, under current technological conditions, heat flux detection devices suffer from the following problems when applied to the aforementioned scenarios due to their inherent structural limitations: First, existing heat flux detection devices can only measure the total heat flux or a single component of the total heat flux (net radiative heat flux or net convective heat flux) within the combustor, and cannot simultaneously and effectively measure the total heat flux and its individual components (net radiative heat flux and net convective heat flux). This results in incomplete measurements, thus affecting the effectiveness of the thermal protection design. Second, existing heat flux detection devices have low measurement accuracy and slow response speed, which also affects the effectiveness of the thermal protection design. Therefore, it is necessary to invent a high-frequency composite heat flux detection device suitable for aero-engine combustors to solve the problems of incomplete measurement, low measurement accuracy, and slow response speed of existing heat flux detection devices when applied to aero-engine combustors. Summary of the Invention

[0003] To address the problems of incomplete measurement, low measurement accuracy, and slow response speed of existing heat flux detection devices when applied to aero-engine combustion chambers, this invention provides a high-frequency composite heat flux detection device suitable for aero-engine combustion chambers.

[0004] This invention is achieved using the following technical solution: A high-frequency composite heat flux detection device suitable for aero-engine combustion chamber includes a cylindrical shell; both the upper and lower ends of the shell are provided with end walls, and the upper end wall of the shell is provided with a first window and a second window; a protective window is sealed and embedded in the upper opening of the first window, and a net radiative heat flux probe is installed in the first window; a total heat flux probe is installed in the second window, and the total heat flux probe is exposed through the second window. The net radiative heat flux probe includes a first substrate; the first substrate is sealed and embedded in the lower end of the first window, and a protective cavity is left between the first substrate and the protective window; the protective cavity is filled with a protective gas; a yttrium barium copper oxide sensitive layer and a first heat-absorbing layer are stacked and fixed on the upper surface of the first substrate from bottom to top; a first lead and a second lead are respectively connected to the yttrium barium copper oxide sensitive layer. The total heat flux probe includes a second substrate; the second substrate is sealed and embedded in the lower end of the second window; the upper surface of the second substrate is sequentially stacked and fixed with a thermopile sensitive layer, a thermal resistance layer, a protective layer, and a second heat-absorbing layer from bottom to top; a third lead is connected to the first end of the thermopile sensitive layer; a fourth lead is connected to the tail end of the thermopile sensitive layer; a fifth lead is connected to the fourth lead; the third lead and the fifth lead are made of the same material; the fourth lead and the fifth lead are made of different materials.

[0005] Furthermore, a first terminal and a second terminal are fixed on the upper surface of the first substrate; the first terminal is connected to the first lead; the second terminal is connected to the second lead; a third terminal, a fourth terminal, and a fifth terminal are also fixed on the upper surface of the second substrate; the third terminal is connected to the third lead; the fourth terminal is connected to the fourth lead; and the fifth terminal is connected to the fifth lead.

[0006] Furthermore, a heat sink is sealed and embedded inside the housing, and the upper surface of the heat sink is fixed to the lower surface of the first base and the lower surface of the second base, respectively; a cooling pipe with a spiral structure is fixed to the lower surface of the heat sink; the two ends of the cooling pipe are respectively connected to the first conduit and the second conduit; a circulation pump is fixed to the lower inner end face of the housing; the inlet of the circulation pump is connected to the first conduit; and the outlet of the circulation pump is connected to the second conduit.

[0007] Furthermore, the shell is made of heat-insulating material; the protective window is made of polycrystalline spinel or sapphire; the first substrate, the second substrate, and the protective layer are all made of aluminum oxide; the first heat-absorbing layer and the second heat-absorbing layer are both made of graphene doped with gold gratings; the first lead and the second lead are both made of copper; the thermopile sensitive layer is composed of multiple pairs of R-type thermocouples connected in series; the thermal resistance layer is made of silicon dioxide; the third lead and the fifth lead are both made of platinum; and the fourth lead is made of platinum-rhodium alloy.

[0008] Furthermore, the first, second, third, fourth, and fifth terminals are all high-temperature resistant ceramic terminals.

[0009] Furthermore, a first through hole is provided in the upper part of the wall of the first window hole; a second through hole is provided in the upper part of the wall of the second window hole.

[0010] Furthermore, a third through hole is provided in the lower part of the side wall of the housing.

[0011] Compared with existing heat flux detection devices, the high-frequency composite heat flux detection device for aero-engine combustion chambers described in this invention, based on a dual-probe structure, achieves real-time, high-precision transient measurement of composite thermal parameters (total heat flux, net radiative heat flux, net convective heat flux, and temperature). This provides the following advantages: First, this invention can simultaneously and effectively measure the total heat flux and its individual components (net radiative heat flux and net convective heat flux) within the combustion chamber, resulting in more comprehensive measurements and significantly improving the effectiveness of thermal protection design. Second, this invention offers higher measurement accuracy and faster response speed, further enhancing the effectiveness of thermal protection design.

[0012] This invention effectively solves the problems of incomplete measurement, low measurement accuracy, and slow response speed of existing heat flux detection devices when applied to aero-engine combustion chambers, and is suitable for thermal protection design of aero-engine combustion chambers. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the present invention.

[0014] Figure 2 yes Figure 1 AA sectional view.

[0015] Figure 3 yes Figure 1 BB cross-sectional view.

[0016] Figure 4 yes Figure 1 Top view.

[0017] Figure 5 yes Figure 4 CC section view.

[0018] Figure 6 yes Figure 4 A partial structural diagram.

[0019] Figure 7 yes Figure 6 DD sectional view.

[0020] Figure 8 yes Figure 6 EE sectional view.

[0021] Figure 9 This is a schematic diagram of the net radiative heat flux probe in this invention.

[0022] Figure 10 yes Figure 9 Top view.

[0023] Figure 11 This is a schematic diagram of the total heat flux probe in this invention.

[0024] Figure 12 yes Figure 11 Top view.

[0025] Figure 13 yes Figure 11 A partial structural diagram.

[0026] Figure 14 yes Figure 13 Top view.

[0027] In the diagram: 1-Shell, 1.1-First window, 1.2-Second window, 1.3-First wiring hole, 1.4-Second wiring hole, 1.5-Third wiring hole, 2-Protective window, 3-First substrate, 4-Yttrium barium copper oxide sensitive layer, 5-First heat-absorbing layer, 6-First lead, 7-Second lead, 8-Second substrate, 9-Thermopile sensitive layer, 10-Thermal resistance layer, 11-Protective layer, 12-Second heat-absorbing layer, 13-Third lead, 14-Fourth lead, 15-Fifth lead, 16-First terminal, 17-Second terminal, 18-Third terminal, 19-Fourth terminal, 20-Fifth terminal, 21-Heat sink, 22-Cooling pipe, 23-First conduit, 24-Second conduit, 25-Circulation pump. Detailed Implementation

[0028] A high-frequency composite heat flux detection device suitable for aero-engine combustion chambers includes a cylindrical housing 1; both the upper and lower ends of the housing 1 are provided with end walls, and the upper end wall of the housing 1 is provided with a first window 1.1 and a second window 1.2; a protective window 2 is sealed and embedded in the upper opening of the first window 1.1, and a net radiative heat flux probe is installed in the first window 1.1; a total heat flux probe is installed in the second window 1.2, and the total heat flux probe is exposed through the second window 1.2. The net radiative heat flux probe includes a first substrate 3; the first substrate 3 is sealed and embedded in the lower end opening of the first window 1.1, and a protective cavity is left between the first substrate 3 and the protective window 2; the protective cavity is filled with a protective gas; a yttrium barium copper oxide sensitive layer 4 and a first heat-absorbing layer 5 are sequentially stacked and fixed on the upper surface of the first substrate 3 from bottom to top; a first lead wire 6 and a second lead wire 7 are respectively connected to the yttrium barium copper oxide sensitive layer 4; The total heat flux probe includes a second substrate 8; the second substrate 8 is sealed and embedded in the lower end of the second window 1.2; the upper surface of the second substrate 8 is sequentially stacked and fixed with a thermopile sensitive layer 9, a thermal resistance layer 10, a protective layer 11, and a second heat-absorbing layer 12 from bottom to top; the first end of the thermopile sensitive layer 9 is connected to a third lead 13; the tail end of the thermopile sensitive layer 9 is connected to a fourth lead 14; a fifth lead 15 is connected to the fourth lead 14; the third lead 13 and the fifth lead 15 are made of the same material; the fourth lead 14 and the fifth lead 15 are made of different materials.

[0029] In operation, this invention is installed inside the combustion chamber of an aircraft engine. A first data acquisition card, a second data acquisition card, a third data acquisition card, and a host computer are selected. The first lead 6 and the second lead 7 are both connected to the first data acquisition card. The third lead 13 and the fourth lead 14 are both connected to the second data acquisition card. The fourth lead 14 and the fifth lead 15 are both connected to the third data acquisition card. The first, second, and third data acquisition cards are all connected to the host computer.

[0030] The specific work process includes: I. Measurement of Net Radiative Heat Flux: When the total heat flux in the combustion chamber acts on the protective window 2, the net convective heat flux in the total heat flux is shielded by the protective window 2, while the net radiative heat flux in the total heat flux passes through the protective window 2 into the protective cavity. It is then absorbed by the first heat-absorbing layer 5 and acts on the yttrium barium copper oxide sensitive layer 4, where it is converted into a potential difference signal. The first data acquisition card acquires this potential difference signal in real time via the first lead 6 and the second lead 7, and transmits the acquisition results to the host computer. The host computer can calculate the net radiative heat flux based on the acquisition results and the pre-calibrated relationship curve.

[0031] II. Measurement of Total Heat Flux and Temperature: The total heat flux in the combustion chamber is directly absorbed by the second heat-absorbing layer 12, and then acts on the thermopile sensitive layer 9 sequentially through the protective layer 11 and the thermal resistance layer 10. The heat flux is then converted into a potential difference signal by the thermopile sensitive layer 9. The second data acquisition card acquires this potential difference signal in real time through the third lead 13 and the fourth lead 14, and transmits the acquisition results to the host computer. The host computer can calculate the total heat flux based on the acquisition results and the pre-calibrated relationship curve. Simultaneously, the third data acquisition card acquires the potential difference signal between the fourth lead 14 and the fifth lead 15 in real time, and transmits the acquisition results to the host computer. The host computer can calculate the temperature based on the acquisition results and the pre-calibrated relationship curve.

[0032] III. Measurement of net convective heat flux: The net convective heat flux can be obtained by subtracting the calculated total heat flux from the net radiative heat flux using the host computer.

[0033] In the above process, the protective gas prevents the net radiative heat flux probe from oxidizing and failing under high-temperature conditions. The thermal resistance layer 10 generates a temperature gradient to calculate the total heat flux using Fourier's law of thermal conductivity. The protective layer 11 enhances the total heat flux probe's resistance to high temperatures and oxidation.

[0034] The upper surface of the first substrate 3 is also fixed with a first terminal 16 and a second terminal 17; the first terminal 16 is connected to the first lead 6; the second terminal 17 is connected to the second lead 7; the upper surface of the second substrate 8 is also fixed with a third terminal 18, a fourth terminal 19, and a fifth terminal 20; the third terminal 18 is connected to the third lead 13; the fourth terminal 19 is connected to the fourth lead 14; and the fifth terminal 20 is connected to the fifth lead 15. During operation, a first wire connects the first data acquisition card to the first terminal 16, and the first lead 6 is connected to the first data acquisition card sequentially through the first terminal 16 and the first wire. A second wire connects the first data acquisition card to the second terminal 17, and the second lead 7 is connected to the first data acquisition card sequentially through the second terminal 17 and the second wire. A third wire connects the second data acquisition card to the third terminal 18, and the third lead 13 is connected to the second data acquisition card sequentially through the third terminal 18 and the third wire. A fourth wire connects the second data acquisition card to the fourth terminal 19. The fourth lead 14 is connected to the second data acquisition card via the fourth terminal 19 and the fourth wire. A fifth wire connects the third data acquisition card to the fourth terminal 19. The fourth lead 14 is connected to the third data acquisition card via the fourth terminal 19 and the fifth wire. A sixth wire connects the third data acquisition card to the fifth terminal 20. The fifth lead 15 is connected to the third data acquisition card via the fifth terminal 20 and the sixth wire.

[0035] A heat sink 21 is sealed and embedded inside the housing 1, and the upper surface of the heat sink 21 is fixed to the lower surface of the first base 3 and the lower surface of the second base 8, respectively. A spiral cooling pipe 22 is fixed to the lower surface of the heat sink 21. The two ends of the cooling pipe 22 are connected to the first conduit 23 and the second conduit 24, respectively. A circulation pump 25 is fixed to the lower inner end face of the housing 1. The inlet of the circulation pump 25 is connected to the first conduit 23, and the outlet of the circulation pump 25 is connected to the second conduit 24. During operation, the circulation pump 25 stores coolant. Under the pumping action of the circulation pump 25, the coolant flows from the circulation pump 25, sequentially through the second conduit 24, the cooling pipe 22, and the first conduit 23, and then returns to the circulation pump 25. When flowing through the cooling pipe 22, the coolant exchanges heat with the heat sink 21, thereby circulating and cooling the net radiative heat flux probe and the total heat flux probe.

[0036] The shell 1 is made of heat-insulating material; the protective window 2 is made of polycrystalline spinel or sapphire; the first substrate 3, the second substrate 8, and the protective layer 11 are all made of aluminum oxide; the first heat-absorbing layer 5 and the second heat-absorbing layer 12 are all made of graphene doped with gold gratings; the first lead 6 and the second lead 7 are both made of copper; the thermopile sensitive layer 9 is composed of multiple pairs of R-type thermocouples connected in series; the thermal resistance layer 10 is made of silicon dioxide; the third lead 13 and the fifth lead 15 are both made of platinum; and the fourth lead 14 is made of platinum-rhodium alloy.

[0037] The first terminal 16, the second terminal 17, the third terminal 18, the fourth terminal 19, and the fifth terminal 20 are all high-temperature resistant ceramic terminals.

[0038] A first through-hole 1.3 is provided through the upper part of the wall of the first window 1.1; a second through-hole 1.4 is provided through the upper part of the wall of the second window 1.2. During operation, the first through-hole 1.3 allows the first and second wires to pass through. The second through-hole 1.4 allows the third, fourth, fifth, and sixth wires to pass through.

[0039] A third wiring hole 1.5 is provided through the lower part of the side wall of the housing 1. During operation, a power cord is threaded through the third wiring hole 1.5, and the power supply terminal of the circulating pump 25 is connected to an external power source through the power cord.

[0040] In specific implementation, the protective gas is argon. The yttrium barium copper oxide sensitive layer 4 is grown on the upper surface of the first substrate 3 using pulsed laser deposition technology. The thickness of the thermopile sensitive layer 9 and the thermal resistance layer 10 are both 3 μm. The thickness of the protective layer 11 is 4 μm.

[0041] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A high frequency complex heat flux probe suitable for use in an aeroengine combustion chamber, characterised in that: The shell (1) comprises a cylindrical structure; the upper and lower ends of the shell (1) are provided with end walls, and the upper end wall of the shell (1) is provided with a first window hole (1.1) and a second window hole (1.2); a protective window (2) is sealingly embedded in the upper end opening of the first window hole (1.1), and a net radiant heat flux probe is installed in the first window hole (1.1); a total heat flux probe is installed in the second window hole (1.2), and the total heat flux probe is exposed through the second window hole (1.2); The net radiant heat flux probe comprises a first base (3); the first base (3) is sealingly embedded in the lower end opening of the first window hole (1.1), and a protection cavity is left between the first base (3) and the protective window (2); the protection cavity is filled with a protective gas; the upper surface of the first base (3) is sequentially stacked and fixed from bottom to top with a yttrium-barium-copper oxygen sensitive layer (4) and a first heat absorbing layer (5); the yttrium-barium-copper oxygen sensitive layer (4) is respectively connected with a first lead wire (6) and a second lead wire (7); The total heat flux probe comprises a second base (8); the second base (8) is sealingly embedded in the lower end opening of the second window hole (1.2); the upper surface of the second base (8) is sequentially stacked and fixed from bottom to top with a thermoelectric pile sensitive layer (9), a thermal resistance layer (10), a protective layer (11), and a second heat absorbing layer (12); the leading end of the thermoelectric pile sensitive layer (9) is connected with a third lead wire (13); the tail end of the thermoelectric pile sensitive layer (9) is connected with a fourth lead wire (14); the fourth lead wire (14) is connected with a fifth lead wire (15); the third lead wire (13) and the fifth lead wire (15) are made of the same material; the fourth lead wire (14) and the fifth lead wire (15) are made of different materials.

2. A high frequency complex heat flux probe suitable for use in a combustion chamber of an aeroengine according to claim 1, characterised in that: The upper surface of the first base (3) is also fixed with a first terminal post (16) and a second terminal post (17); the first terminal post (16) is connected with the first lead wire (6); the second terminal post (17) is connected with the second lead wire (7); the upper surface of the second base (8) is also fixed with a third terminal post (18), a fourth terminal post (19), and a fifth terminal post (20); the third terminal post (18) is connected with the third lead wire (13); the fourth terminal post (19) is connected with the fourth lead wire (14); the fifth terminal post (20) is connected with the fifth lead wire (15).

3. A high frequency complex heat flux probe suitable for use in a combustion chamber of an aeroengine according to claim 1, characterised in that: A heat sink body (21) is sealingly embedded in the shell (1), and the upper surface of the heat sink body (21) is fixed with the lower surface of the first base (3) and the lower surface of the second base (8); the lower surface of the heat sink body (21) is fixed with a cooling pipe (22) in a spiral structure; the two ends of the cooling pipe (22) are respectively communicated with a first conduit (23) and a second conduit (24); a circulating pump (25) is fixed to the lower inner end surface of the shell (1); the inlet of the circulating pump (25) is communicated with the first conduit (23); the outlet of the circulating pump (25) is communicated with the second conduit (24).

4. A high frequency complex heat flux probe suitable for use in a combustion chamber of an aeroengine according to claim 1, characterized in that: The shell (1) is made of heat insulation material; the protective window (2) is made of polycrystalline spinel or sapphire; the first base (3), the second base (8) and the protective layer (11) are all made of aluminum oxide; the first heat absorption layer (5) and the second heat absorption layer (12) are both made of graphene doped with gold grating; the first lead wire (6) and the second lead wire (7) are both made of copper; the thermoelectric sensitive layer (9) is made of multiple pairs of R-type thermocouples connected in series; the thermal resistance layer (10) is made of silicon dioxide; the third lead wire (13) and the fifth lead wire (15) are both made of platinum; and the fourth lead wire (14) is made of platinum-rhodium alloy.

5. A high frequency complex heat flux probe suitable for use in a combustion chamber of an aeroengine according to claim 2, characterised in that: The first terminal post (16), the second terminal post (17), the third terminal post (18), the fourth terminal post (19) and the fifth terminal post (20) are all high-temperature-resistant ceramic terminal posts.

6. A high frequency complex heat flux probe suitable for use in a combustion chamber of an aeroengine according to claim 2, characterised in that: A first threading hole (1.3) is formed through the upper part of the hole wall of the first window hole (1.1); and a second threading hole (1.4) is formed through the upper part of the hole wall of the second window hole (1.2).

7. A high frequency complex heat flux probe suitable for use in a combustion chamber of an aeroengine according to claim 3, characterised in that: A third threading hole (1.5) is formed through the lower part of the side wall of the shell (1).

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