CN115436066A - A device for measuring dynamic total pressure of intake air distortion flow field - Google Patents

Abstract

The invention belongs to the technical field of dynamic total pressure parameter testing, and particularly relates to a device for measuring dynamic total pressure of an intake distorted flow field. The intake distortion flow field area is large, if the dynamic total pressure measurement is carried out on the intake distortion flow field area, a multi-point dynamic total pressure probe comb is generally adopted, and the traditional measurement method has the following problems: the number of probe combs is large, and the blockage of a convection field is large; (2) The probe structure of the probe comb has a small insensitive angle to the airflow direction and low frequency response; and (3) low utilization efficiency and high cost. In order to solve the problems, the invention consists of a probe comb support rod, a single-hole dynamic total pressure probe, a mounting seat and a rotating mechanism, can reduce the number of pressure sensors and the number of probe combs, weaken the interference of the probe comb support rod on a measured flow field, simplify test operation, reduce test cost, increase an insensitive angle of the probe for measurement, improve measurement frequency response, realize 360-degree all-around measurement on a certain plane of the flow field to be measured, and improve test precision.

Description

A device for measuring dynamic total pressure of intake air distortion flow field

technical field

The invention belongs to the technical field of dynamic total pressure parameter testing, and in particular relates to a device for measuring the dynamic total pressure of an intake air distortion flow field.

Background technique

Total pressure distortion is a phenomenon of uneven distribution of total pressure in the circumferential or radial direction, which will cause loss of engine performance and cause stability problems. Severe total pressure distortion will cause fan/compressor stall or surge, and the engine will enter Unstable working conditions may even cause the engine to stop in the air, resulting in a serious accident of the aircraft; at the same time, the total pressure distortion will also cause structural damage and failure of the engine; the total pressure distortion will induce the synchronous vibration response of the fan/compressor blade and the wheel , causing the combustion temperature field in the combustion chamber to be uneven, causing problems such as excessive thermal stress on the turbine blades and premature damage;

In the initial study of pressure distortion, only the steady-state total pressure distortion was considered, but it was gradually found that only considering the steady-state total pressure distortion was not sufficient, and the dynamic total pressure distortion had a different impact from the steady-state total pressure distortion; due to the pressure fluctuation The existence of the engine inlet flow will cause fluctuations in performance loss; on the other hand, due to the existence of pressure fluctuations, the actual dynamic peak total pressure distortion value will be greater than the steady-state total pressure distortion value, thus bringing about stability sexual influence;

The air intake distorted flow field has a large area. If the dynamic total pressure is to be measured, a multi-point dynamic total pressure probe comb is generally used. Usually, it is required to arrange 6 probe combs in the word "water" at equal angles in the circumferential direction or form a Eight probe combs are arranged in the word "米"; the traditional measurement method has the following problems: (1) The number of probe combs is large, and the blockage of the flow field is large; (2) The probe structure of the probe comb is not sensitive to the direction of the airflow. , the frequency response is low, which makes the measurement error larger; (3) The sensor adopts a mosaic connection method, which cannot be removed after installation. If one sensor is damaged, the entire probe comb will be scrapped, and the utilization efficiency is low.

Contents of the invention

The technical problem to be solved by the present invention is to obtain the dynamic total pressure parameter of the intake distortion flow field; for this reason, the present invention specifically relates to a device for measuring the dynamic total pressure of the intake distortion flow field to solve the problems existing in the traditional testing method insufficient.

Design scheme of the present invention is:

1. A device for measuring the dynamic total pressure of the intake air distortion flow field consists of a probe comb support rod (1), a single-hole dynamic total pressure probe (2), a mounting base (3), and a rotating mechanism (4), The pressure sensor (8) is fixed on the single-hole dynamic total pressure probe (2) by glue, and the single-hole dynamic total pressure probe (2) is installed on the probe comb support rod (1) through the thread (7). The comb is installed on the rotating mechanism (4) through the mounting seat (3);

2. Furthermore, the single-hole dynamic total pressure probe (2) is a ball-and-socket shape (9), and its section line is 1/4 circle; the probe has a small round hole (5), which can be disassembled with a special fixture; The tail of the probe is designed with an undercut (6) and a thread (7) behind the undercut. ;

3. Furthermore, the probe comb support rod (1) is slotted (12) at the rear for the arrangement of the pressure sensor cable; the threaded hole (13) is opened at the front for the installation of the single-hole dynamic total pressure probe (2); the probe The layout can be arranged according to the iso-annular surface, or can be arranged according to the Chebyshev integral method and the logarithmic linear method; after installing the single-hole dynamic total pressure probe (2), fill the material, seal the slot (12) opened at the rear, Realize the fixation of the pressure sensor cable, and ensure that the airflow will not enter from the slot at the rear of the probe comb support rod, so as to avoid affecting the measurement, and at the same time enhance the strength of the probe comb support rod.

4. Further, through the designed four round holes (10), combine the bolts to fix the probe comb on the rotating mechanism (4); the front part of the mounting seat is designed with a straight section (11) for positioning;

5. Further, the rotating mechanism (4) is mainly composed of a gear transmission mechanism (14) and a motor (15), which realizes 360° rotation of the probe comb around the axial direction;

The present invention can reduce the number of pressure sensors and the number of probe combs, weaken the interference of the probe comb struts on the measured flow field, simplify the test operation, reduce the test cost, and increase the insensitivity angle of the probe measurement , Improve the measurement frequency response, realize the 360° all-round measurement of a certain plane of the flow field to be measured, and improve the test accuracy.

Compared with the traditional test scheme, the beneficial effects of the present invention are:

Beneficial effect one: the insensitive angle of the total pressure probe is improved; the single-hole total pressure probe on the traditional probe comb adopts a 45° inner chamfer. The inventor has compared various probe structures through numerical simulation and experiments, and found that The ball-and-socket probe has a larger insensitivity angle, which can reach 50°, which improves the measurement accuracy;

Beneficial effect 2: The frequency response of the total pressure probe is improved; the single-hole total pressure probe on the traditional probe comb generally uses a pressure introduction tube, or the pressure sensor is installed at the rear of the single-hole total pressure probe. This installation method leads to The cavity effect is obvious, and the measurement frequency response is low; the present invention installs the pressure sensor directly on the single-hole total pressure probe, the cavity between the sensor and the pressure sensing hole is small, the cavity effect is not obvious, and the frequency response of the probe is high , can reach 100kHz;

Beneficial effect three: the number of measurement points is increased; the traditional test plan is to arrange 6 probe combs at equal angles in the shape of "water" or 8 probe combs at equal angles in the shape of "m" on the cross-section to be tested, which cannot be used The method of the present invention utilizes the rotation mechanism to rotate the probe comb to realize the multi-point measurement because the traditional probe comb total pressure probe is stable and is measured through the pressure induction tube, or the pressure sensor is arranged on the probe The rear part has a low measurement frequency response, and the distorted flow field is dynamic. If it is rotated, the traditional probe comb cannot meet the measurement frequency response requirements, and the accuracy of the measurement results is very low; the present invention uses a rotating mechanism, which can Realize 360° dynamic measurement, the number of measurement points is several times or even dozens of times that of the traditional solution, which improves the measurement accuracy;

Beneficial effect 4: high utilization rate and reduced test cost; the traditional probe comb adopts an integrated design as a whole, that is, the probe is often embedded on the probe comb support rod, and if one probe is damaged, the entire probe comb will be scrapped; The present invention adopts a refined design, and focuses on reusable and detachable, especially in the design of the probe, which is designed with a small round hole and thread for disassembly. If a probe is damaged, only a single probe needs to be reprocessed to replace it. The cost is much lower than that of the whole probe comb, and the overall utilization rate is high, which reduces the test cost.

Description of drawings

Figure 1 is a schematic diagram of the device for measuring the dynamic total pressure of the intake distortion flow field.

Fig. 2 is a front view of Fig. 1 .

Figure 3 is a schematic diagram of a single-hole dynamic pressure probe.

FIG. 4 is a sectional view of FIG. 3 .

FIG. 5 is a schematic diagram of the probe comb rod in FIG. 3 .

FIG. 6 is a rear view of FIG. 5 .

Among them: 1-probe comb support rod, 2-single-hole dynamic total pressure probe, 3-mounting seat, 4-rotation mechanism, 5-small round hole on the probe, 6-relief groove, 7-thread at the rear of the probe , 8-pressure sensor, 9-ball socket, 10-round hole on the mounting seat, 11-straight section on the mounting seat, 12-slot at the rear of the probe comb rod, 13-threaded hole, 14- Gear transmission mechanism, 15-motor.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 3 and Figure 4, the outer diameter of the single-hole total pressure probe (2) is 5 mm, and the inner diameter is 1.8 mm; the small round hole (5) opened in the middle of the single-hole total pressure probe (2) has a diameter of 1 mm and a depth of 1 mm. The probe at the opening is thickened, with an outer diameter of 6mm; the length of the front part of the single-hole total pressure probe (2), that is, the part in front of the undercut (6), is 10mm; the undercut width is 1mm, and the depth is 0.5mm; the single-hole total pressure The thread (7) at the rear of the probe (2) is a standard thread of M5×0.5 with a length of 7mm; A 1/4 arc line with a radius of 1.6 mm; a pressure sensor (8) is installed inside the single-hole total pressure probe (2);

As shown in Fig. 5 and Fig. 6, six M5×0.5 threaded holes (13) with a depth of 7mm are opened on the probe comb rod (1), and the holes are arranged along the radial iso-annular surface. The distance between the center of the hole and the center of the bottom of the mounting seat is 19.5mm, 60.5mm, 106.5mm, 160.5mm, 226.5mm, and 321.5mm; Equivalent strength design, groove (12) on the back, the width of the groove (12) is 5mm, and the length is 310mm; The diameter is 10mm, through the mounting base, the distance between the center of the round hole (10) and the center of the mounting base (3) is 80mm; the length of the straight section on the mounting base (3) is 30mm;

As shown in Figure 1 and Figure 2, the rotating mechanism (4) is mainly composed of a motor (14) and a gear transmission mechanism (13). The single-hole total pressure probe is installed (2) on the probe comb rod (1), Then it is integrally installed on the rotating mechanism (4) to measure the dynamic total pressure of the air intake distortion flow field of the aeroengine;

The invention can be installed on the inner wall surface of the transition section of the aeroengine air intake, the probe comb is installed firmly, the structural strength is reliable, and the measurement of the dynamic total pressure of the air intake distortion flow field can be realized.

Claims (1)

1. The utility model provides a device for measuring intake distortion flow field developments are total presses which characterized in that: the probe comb is composed of a probe comb supporting rod (1), a single-hole dynamic total pressure probe (2), a mounting seat (3) and a rotating mechanism (4), wherein a pressure sensor (8) is fixed on the single-hole dynamic total pressure probe (2) in a gluing mode, the single-hole dynamic total pressure probe (2) is installed on the probe comb supporting rod (1) through a thread (7), and a probe comb is installed on the rotating mechanism (4) through the mounting seat (3);

the single-hole dynamic total pressure probe (2) is in a spherical socket shape (9), and the section profile of the probe is 1/4 of the circumference; the probe is provided with a small round hole (5) which can be disassembled and assembled by a special fixture; the tail part of the probe is provided with a tool withdrawal groove (6) and a thread (7) behind the tool withdrawal groove. (ii) a

A groove (12) is formed in the rear part of the probe comb support rod (1) so as to arrange a pressure sensor cable; the front part of the device is provided with a threaded hole (13) so as to install a single-hole dynamic total pressure probe (2); the arrangement mode of the probe can be arranged according to an isotorus, and also can be arranged according to a Chebyshev integral method and a logarithmic linear method; after the single-hole dynamic total pressure probe (2) is installed, the rear-opened groove (12) is sealed by filling materials, the pressure sensor cable is fixed, the air flow is guaranteed not to enter from the rear-opened groove of the probe comb supporting rod, the influence on measurement is avoided, and meanwhile the strength of the probe comb supporting rod is enhanced.

The probe comb is fixed on the rotating mechanism (4) through four designed round holes (10) in combination with bolts; the front part of the mounting seat is designed with a straight section (11) for positioning;

the rotating mechanism (4) mainly comprises a gear transmission mechanism (14) and a motor (15), and the probe comb can rotate 360 degrees around the axis direction;

the invention can reduce the number of pressure sensors and the number of probe combs, weaken the interference of the probe comb support rods on a measured flow field, simplify test operation, reduce test cost, increase the probe measurement insensitive angle which can reach 50 degrees, improve measurement frequency response which can reach 100kHz, realize 360-degree all-dimensional measurement on a certain plane of the flow field to be measured, and improve test precision.

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