A fast-response total temperature probe with small temperature measurement deviation

Abstract

A fast-response total temperature probe with small temperature measurement deviation includes a support rod housing and multiple stagnation shields inserted into the support rod housing. The stagnation shields are spaced apart along the axial direction of the support rod housing, and the axial direction of the stagnation shields is perpendicular to the support rod housing. Each stagnation shield has a through-hole in the axial direction, with one end serving as an air inlet and the other end as an exhaust outlet. The area of ​​the exhaust outlet is smaller than the area of ​​the air inlet. Each stagnation shield is equipped with a set of thermocouple wires, which are inserted inside the support rod housing. The thermocouple wire balls are all located within the inner cavity of the support rod housing and are positioned within the axial through-holes relative to the stagnation shields. The total temperature probe provided by this invention improves the response speed of the temperature measurement probe while reducing temperature measurement radiation errors compared to traditional probes.

Description

Technical Field

[0001] This invention relates to the field of aero-engine airflow temperature testing technology, and in particular to a fast-response total temperature probe with small temperature measurement deviation. Background Technology

[0002] Testing the temperature field behind the turbine of an aero-engine requires the use of a test probe. In the existing technology, there are relevant documents that disclose the technology of test probes for airflow temperature of aero-engines.

[0003] For example, patent application CN106918410A discloses a total temperature blade-shaped probe. This probe does not require a probe support rod and can simultaneously measure the total temperature at multiple points between blade rows. The measurement time is short. The stagnation shrouds in this probe have different axial directions, each facing the expected incoming flow direction, which can reduce the total temperature measurement error of the probe. It can more accurately and comprehensively measure the distribution of total temperature at the rotor outlet or between stages of the impeller machinery along the blade height direction, thereby improving the measurement accuracy of total temperature data.

[0004] For example, patent CN212082624U discloses a radiation-proof total temperature measurement probe, which consists of a stagnation cover, a temperature sensor, an insulating seal, a convection heat exchange hole, a probe support, a temperature measuring lead, and a shield. This probe has a large air intake, rapid heat exchange on the temperature sensor surface, and a wide range of airflow insensitivity angles, enabling accurate measurement of the total temperature of a flow field with large airflow deflection angles and significant changes in operating conditions. This probe effectively shields against radiation and protects the temperature sensor, allowing for accurate measurement of the total temperature of the flow field under high-temperature conditions.

[0005] In existing technologies, thermocouple wires are easily affected by the low-temperature engine components and casing walls during temperature measurement, resulting in radiation errors. Furthermore, when measuring the temperature field behind the engine turbine, it is necessary to minimize the measurement time. However, with existing probe structures, the total amount of heat exchange airflow generated by the thermocouple wires per unit time is low, affecting the thermocouple's response speed, and the response time cannot meet operational requirements. Summary of the Invention

[0006] The main objective of this invention is to propose a fast-response total temperature probe with small temperature measurement deviation, which reduces radiation error while accelerating heat exchange of the thermocouple wire, thereby reducing the temperature measurement deviation of the probe and improving the response speed of the probe, thus solving the above-mentioned technical problems.

[0007] To achieve the above objectives, this invention proposes a fast-response total temperature probe with small temperature measurement deviation, comprising a support rod housing and multiple stagnation shields inserted into the support rod housing. The multiple stagnation shields are spaced apart along the axial direction of the support rod housing, and the axial direction of the stagnation shields is perpendicular to the support rod housing. Each stagnation shield is provided with a through-hole in the axial direction, one end of which is an air inlet and the other end is an exhaust outlet, the area of ​​which is smaller than the area of ​​the air inlet. Each stagnation shield is provided with a set of thermocouple wires, which are inserted inside the support rod housing. The thermocouple wire balls are all located within the inner cavity region of the support rod housing and are positioned in the axial through-holes relative to the stagnation shields.

[0008] Preferably, the support rod housing is a hollow shell structure, and the inner cavity of the support rod housing is filled with high-temperature bauxite cement.

[0009] Preferably, a probe mounting base is provided at one end of the support rod housing, and a sleeve is inserted into the inner hole of the probe mounting base. The thermocouple wire passes through the sleeve and extends into the interior of the support rod housing.

[0010] Furthermore, the sleeve is made of polytetrafluoroethylene.

[0011] Preferably, the stagnation cover includes an insertion part and an external part; the diameter of the insertion part is smaller than the diameter of the external part, and the insertion part is inserted into the support rod housing; a limiting step is formed between the insertion part and the external part and abuts against the outer cylindrical surface of the support rod housing.

[0012] Furthermore, the external parts of each stagnation cover are located on the same side of the support rod housing, and the height of each external part is different. From the outer end to the inner end of the support rod housing, the height of each external part decreases sequentially.

[0013] Preferably, the limiting step is welded and fixed to the outer cylindrical surface of the support rod housing.

[0014] Preferably, a radial insertion hole is provided on the cylindrical surface of the stagnation cover, and the thermocouple wire ball head extends into the axial through hole of the stagnation cover through the radial insertion hole; a retaining ring is provided on the outer cylindrical surface of the stagnation cover at the position of the radial insertion hole; a retaining block is fixedly connected to the thermocouple wire near the thermocouple wire ball head; the retaining block is inserted into the retaining ring; the retaining block is a double-hole ceramic tube.

[0015] Preferably, a bevel is provided on the end face of the support rod housing at the end away from the probe mounting base.

[0016] Preferably, an external thread is provided on the outer peripheral surface of the probe mounting base.

[0017] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows:

[0018] (1) In this invention, the thermocouple wire is inserted inside the support rod housing. The support rod housing forms a fully shielded structure for the thermocouple wire, "wrapping" the thermocouple wire inside. During the temperature measurement process, the influence of the engine components and casing wall with lower temperature on the thermocouple wire is reduced, that is, the radiation influence of the engine components around the measuring point is reduced, and the radiation error of the total temperature probe is reduced.

[0019] (2) In this invention, the stagnation cover is provided with a through-hole, and the area of ​​the exhaust port of the stagnation cover is smaller than the area of ​​the air inlet. This structure makes the stagnation cover form a "nozzle" structure. The exhaust port structure with a narrow opening is used to speed up the exhaust speed. During the test, the airflow will be accelerated in the stagnation cover, which effectively increases the airflow that exchanges heat with the ferrule head per unit time and reduces the response time of the probe.

[0020] (3) In this invention, the double-hole ceramic tube structure is used to fix the axial through hole of the stagnation cover by interlocking the locking block and the locking ring, and then the wire is routed from inside the support rod housing. This improves the space utilization rate and allows more measuring points to be arranged when the size of the support rod housing is fixed. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the total temperature probe provided by the present invention;

[0023] Figure 2 This is a partial schematic diagram of the total temperature probe provided by the present invention.

[0024] Explanation of reference numerals in the attached drawings: 1. Support rod housing; 101. Inclined surface; 2. Locking cover; 201. Insertion part; 202. External part; 203. Snap ring; 204. Radial insertion hole; 3. Air inlet; 4. Exhaust outlet; 5. Thermocouple wire; 6. Thermocouple wire ball head; 7. Probe mounting base; 8. Sleeve; 9. Locking block. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0027] Combination Figure 1 As shown, a fast-response total temperature probe with small temperature measurement deviation includes a support rod housing 1 and multiple stagnation covers 2 inserted on the support rod housing 1. The multiple stagnation covers 2 are spaced apart along the axial direction of the support rod housing 1, and the axial direction of the stagnation covers 2 is perpendicular to the support rod housing 1. The stagnation covers 2 are provided with a through-hole in the axial direction, one end of which is an air inlet 3 and the other end is an exhaust outlet 4. The area of ​​the exhaust outlet 4 is smaller than the area of ​​the air inlet 3. Each stagnation cover 2 is provided with a set of thermocouple wires 5, which are inserted inside the support rod housing 1. The thermocouple wire ball heads 6 of the thermocouple wires 5 are all located in the inner cavity area of ​​the support rod housing 1 and are arranged in the axial through-hole relative to the stagnation cover 2.

[0028] Traditional temperature probes, in order to achieve better stagnation, typically place the thermocouple wire ball head 6 at the inlet end face of the stagnation cover 2. During temperature measurement, the thermocouple wire 5 is easily affected by the low-temperature engine components and casing walls, resulting in radiation errors. This invention, however, by passing the thermocouple wire 5 through the support rod housing 1, which forms a fully shielded structure, effectively "enclosing" the thermocouple wire 5, and with the thermocouple wire ball head 6 located within the inner cavity of the support rod housing 1 and positioned in the axial through-holes relative to the stagnation cover 2, reduces the influence of the low-temperature engine components and casing walls on the thermocouple wire 5 and the thermocouple wire ball head 6 during temperature measurement. This reduces the radiation influence of engine components around the measurement point, thus lowering the radiation error of the total temperature probe.

[0029] Furthermore, combined Figure 1 As shown, the inner cavity of the support rod housing 1 is filled with high-temperature bauxite cement. Filling with high-temperature bauxite cement serves two purposes: firstly, it provides insulation between the thermocouple wires 5; secondly, it fixes the thermocouple wires 5, preventing them from shaking within the inner cavity of the support rod housing 1. Furthermore, high-temperature bauxite cement possesses high-temperature resistance.

[0030] Combination Figure 1As shown, a probe mounting base 7 is provided at one end of the support rod housing 1, and a sleeve 8 is inserted into the inner hole of the probe mounting base 7. The thermocouple wire 5 passes through the sleeve 8 and extends into the interior of the support rod housing 1. This structure serves two purposes: first, it facilitates the installation of the support rod housing 1; second, it allows for sealing after the interior of the support rod housing 1 is filled with high-temperature bauxite cement. Furthermore, the sleeve 8, used for threading the thermocouple wire 5, protects the thermocouple wire 5 and prevents it from rubbing against other parts during use. Moreover, the sleeve 8 is made of polytetrafluoroethylene (PTFE), which possesses excellent high-temperature resistance, electrical insulation, and aging resistance.

[0031] Combination Figure 1 and Figure 2 As shown, the retaining cover 2 includes an insertion part 201 and an external part 202; the diameter of the insertion part 201 is smaller than the diameter of the external part 202, and the insertion part 201 is inserted into the support rod housing 1; a limiting step is formed between the insertion part 201 and the external part 202 and abuts against the outer cylindrical surface of the support rod housing 1. This structure can limit the retaining cover 2. During installation, the insertion part 201 is directly inserted into the support rod housing 1, and the limiting step abuts against the support rod housing 1 to complete the installation. The structure is simple and the assembly is convenient.

[0032] Combination Figure 1 As shown, the external portions 202 of each stagnation cover 2 are located on the same side of the support rod housing 1. The height h of each external portion 202 is different. From the outer end to the inner end of the support rod housing 1 (during testing, the end of the support rod housing 1 away from the probe mounting seat 7 is the outer end, and the end inserted into the probe mounting seat 7 is the inner end), the height h of each external portion 202 decreases sequentially. The inconsistent height h of each external portion 202 is intended to avoid friction with the engine structure. The sequentially decreasing height h of each external portion 202 is designed based on previous measurement results to avoid errors caused by the measuring point being too far from the outlet section.

[0033] Combination Figure 2 As shown, the limiting step is welded and fixed to the outer cylindrical surface of the support rod housing 1. Welding is used for fixation to ensure the firmness of the installation of the retaining cover 2.

[0034] Combination Figure 2 As shown, a radial insertion hole 204 is provided on the cylindrical surface of the stagnation cover 2, and the thermocouple wire ball head 6 of the thermocouple wire 5 extends into the axial through hole of the stagnation cover 2 through the radial insertion hole 204; a retaining ring 203 is provided on the outer cylindrical surface of the stagnation cover 2 at the position of the radial insertion hole 204; a retaining block 9 is fixedly connected to the thermocouple wire 5 near the thermocouple wire ball head 6; the retaining block 9 is inserted into the retaining ring 203; the retaining block 9 is a double-hole ceramic tube. By utilizing the retaining ring 203 and the retaining block 9, it is easy to fix the thermocouple wire ball head 6 and prevent the thermocouple wire ball head 6 from shaking inside the stagnation cover 2.

[0035] Combination Figure 1 As shown, a bevel 101 is provided on the end face of the support rod housing 1 at the end away from the probe mounting seat 7. The purpose of providing the bevel 101 is to avoid friction with the engine structure.

[0036] Combination Figure 1 As shown, an external thread is provided on the outer peripheral surface of the probe mounting base 7. By utilizing the external thread of the probe mounting base 7, it is convenient to install the entire total temperature probe on the engine turbine for testing.

[0037] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A fast-response total temperature probe with small temperature measurement deviation, characterized in that: It includes a support rod housing (1) and multiple retaining covers (2) inserted on the support rod housing (1). The multiple retaining covers (2) are spaced apart along the axial direction of the support rod housing (1), and the axial direction of the retaining covers (2) is perpendicular to the support rod housing (1). The stagnation cover (2) is provided with a through axial hole, one end of which is an air inlet (3) and the other end is an exhaust port (4). The area of ​​the exhaust port (4) is smaller than the area of ​​the air inlet (3). Each stagnation cover (2) is provided with a set of thermocouple wires (5), which are inserted inside the support rod housing (1); the thermocouple wire ball head (6) of the thermocouple wire (5) is located in the inner cavity area of ​​the support rod housing (1) and is set in the axial through hole relative to the stagnation cover (2). The stagnation cover (2) includes an insertion part (201) and an external part (202); the diameter of the insertion part (201) is smaller than the diameter of the external part (202), and the insertion part (201) is inserted into the support rod housing (1); a limiting step is formed between the insertion part (201) and the external part (202) and abuts against the outer cylindrical surface of the support rod housing (1); The external parts (202) of each stagnation cover (2) are located on the same side of the support rod housing (1). The height of each external part (202) is different. From the outer end to the inner end of the support rod housing (1), the height of each external part (202) decreases sequentially. A radial insertion hole (204) is provided on the cylindrical surface of the stagnation cover (2), and the thermocouple wire ball head (6) of the thermocouple wire (5) extends into the axial through hole of the stagnation cover (2) through the radial insertion hole (204); a retaining ring (203) is provided on the outer cylindrical surface of the stagnation cover (2) at the position of the radial insertion hole (204); a retaining block (9) is fixedly connected to the thermocouple wire (5) near the thermocouple wire ball head (6); the retaining block (9) is inserted into the retaining ring (203); the retaining block (9) is a double-hole ceramic tube.

2. The fast-response total temperature probe with small temperature measurement deviation as described in claim 1, characterized in that: The inner cavity of the support rod housing (1) is filled with high-temperature bauxite cement.

3. The fast-response total temperature probe with small temperature measurement deviation as described in claim 1, characterized in that: A probe mounting base (7) is provided at one end of the support rod housing (1), and a sleeve (8) is inserted into the inner hole of the probe mounting base (7). The thermocouple wire (5) passes through the sleeve (8) and extends into the interior of the support rod housing (1).

4. The fast-response total temperature probe with small temperature measurement deviation as described in claim 3, characterized in that: The sleeve (8) is made of polytetrafluoroethylene.

5. The fast-response total temperature probe with small temperature measurement deviation as described in claim 1, characterized in that: The limiting step is welded and fixed to the outer cylindrical surface of the support rod housing (1).

6. The fast-response total temperature probe with small temperature measurement deviation as described in claim 3, characterized in that: An inclined surface (101) is provided on the end face of the support rod housing (1) away from the probe mounting base (7).

7. The fast-response total temperature probe with small temperature measurement deviation as described in claim 3, characterized in that: External threads are provided on the outer peripheral surface of the probe mounting base (7).

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