CN-121977660-A - Standard flow measuring device and multi-test bed flow consistency evaluation method

CN121977660ACN 121977660 ACN121977660 ACN 121977660ACN-121977660-A

Abstract

The invention relates to a flow measurement accuracy evaluation method, in particular to a standard flow measurement device and a multi-test-bed flow consistency evaluation method. The method mainly solves the technical problem that the existing liquid oxygen flow measurement method cannot carry out transverse comparison evaluation on the liquid oxygen flow measurement precision of each test bed. The standard flow measuring device comprises a rectifying tube, a differential pressure tube, a pressure regulating tube, a pressure and temperature measuring unit and a heat insulation structure, and the method comprises the following steps of 1, measuring calibration of the standard flow measuring device, 2, on-site in-situ calibration of the standard flow measuring device, and 3, liquid oxygen flow consistency evaluation of each test bed. According to the invention, the correction flow coefficient is obtained based on the standard flow measurement device, and then the standard flow measurement device is adopted to carry out the comparison and evaluation of the liquid oxygen flow on different test benches based on the correction flow coefficient, so that the transverse comparison and evaluation of the liquid oxygen flow measurement precision of each test bench is realized.

Inventors

CHEN YU
GAO YAN
HE XIANG
XIANG MIN
BAI JIN
ZHU YAOYAO
XI JINYUAN
YANG ZHANWEI
LIANG RUI

Assignees

西安航天动力试验技术研究所

Dates

Publication Date: 20260505
Application Date: 20251219

Claims (9)

1. A standard flow measurement device, comprising: A differential pressure pipe (2) which adopts a venturi pipe; the rectifying tube (1) is arranged at the upstream of the differential pressure tube (2) along the medium flow direction and adopts a porous pore plate structure; The pressure regulating pipe (3) is arranged at the downstream of the differential pressure pipe (2) along the medium flow direction and adopts a porous pore plate structure; And a plurality of groups of pressure and temperature measuring units are respectively arranged on the differential pressure pipe (2), the rectifying pipe (1) and the pressure regulating pipe (3) and are used for measuring the pressure and the temperature at different positions in the differential pressure pipe (2), the rectifying pipe (1) and the pressure regulating pipe (3).
2. Standard flow measurement device according to claim 1, characterized in that the pressure and temperature measurement unit comprises a pressure measurement element (6) and a temperature sensor, the pressure measurement element (6) comprising a pressure sensor or a differential pressure sensor.
3. The standard flow measurement device according to claim 2, characterized in that a plurality of pressure taking holes (4) are formed in the pipe wall of the differential pressure pipe (2), an outer sleeve (7) is sleeved outside the differential pressure pipe (2), a pressure stabilizing cavity (5) is formed between the outer sleeve (7) and the differential pressure pipe (2), pressure measurement elements (6) corresponding to the pressure taking holes (4) in number are arranged on the outer sleeve (7) in the circumferential direction, and mounting points of the pressure measurement elements (6) are staggered with the pressure taking holes (4).
4. A standard flow measurement device according to claim 3, characterized in that the top and circumferential 120 ° spacing of the differential pressure tube (2) are provided with temperature sensors.
5. The standard flow measurement device of any one of claims 1-4, further comprising: the heat insulation structure is sleeved outside the differential pressure pipe (2), the rectifying pipe (1) and the pressure regulating pipe (3); And the measurement and control system is used for collecting data of the pressure and temperature measuring unit, medium flow passing through the differential pressure pipe (2), the rectifying pipe (1) and the pressure regulating pipe (3) and carrying out data processing.
6. A multiple test bed flow consistency evaluation method based on the standard flow measurement device of any one of claims 1 to 4, comprising the steps of: step 1, measuring and calibrating a standard flow measuring device, and determining a standard flow coefficient C of the standard flow measuring device; step 2, performing on-site in-situ calibration on the standard flow measuring device after metering calibration; And 3, carrying out liquid oxygen flow comparison evaluation on liquid oxygen tapping systems carried by different test benches by adopting a standard flow measuring device after in-situ calibration, so as to realize flow consistency evaluation of multiple test benches.
7. The multiple test bed flow consistency evaluation method according to claim 6, wherein the specific operation of step 2 comprises the steps of: the standard flow measuring device after measurement and calibration is arranged in a liquid oxygen tapping system pipeline of a 1# test bed, a sectional liquid level meter is arranged in the liquid oxygen tapping system pipeline of the 1# test bed, and the liquid oxygen flow passing through the standard flow measuring device is measured Monitoring temperature and pressure data corresponding to different parts of a differential pressure pipe, a rectifying pipe and a pressure regulating pipe in a standard flow measuring device, and performing on-site in-situ calibration linear fitting on the standard flow measuring device to obtain a fitting coefficient, wherein a linear fitting formula is as follows: ; In the formula, And A is intercept, b is slope, which is a fitting coefficient; to correct the differential pressure tube throat area, Is the density of the liquid oxygen, and the liquid oxygen is the density of the liquid oxygen, To correct the differential pressure of the inlet and the outlet of the differential pressure pipe.
8. The method for evaluating the uniformity of a flow rate of a plurality of test beds according to claim 7, wherein the throat area of the differential pressure pipe is corrected The calculation method of (1) is that ; Density of liquid oxygen Calculation is performed by differential pressure tube inlet temperature t: ; Correcting differential pressure tube inlet-outlet differential pressure The calculation method of (1) is as follows: ; P hwql =0.011052t+2.112563; wherein t is the inlet temperature of the differential pressure pipe, P iwql is the inlet pressure of the differential pressure pipe, P hwql is the throat pressure of the differential pressure pipe, d is the throat inner diameter of the differential pressure pipe, Is the linear expansion coefficient of the differential pressure tube material.
9. The multiple test bed flow consistency assessment method according to claim 8, wherein the specific operation of step 3 comprises the steps of: Installing the standard flow measuring device after in-situ calibration in a liquid oxygen discharging pipeline of other test benches, arranging a sectional liquid level meter in the liquid oxygen discharging pipeline, respectively acquiring a liquid oxygen flow measuring value of the sectional liquid level meter and a liquid oxygen flow calculating value of the standard flow measuring device, calculating uncertainty of the liquid oxygen flow measuring value and the liquid oxygen flow calculating value, and then analyzing flow consistency of the multiple test benches according to a normalization error En number calculating formula which is: ; wherein: calculating a liquid oxygen flow; is a liquid oxygen flow measurement; uncertainty of the calculated value for the liquid oxygen flow; Is the uncertainty of the liquid oxygen flow measurement.

Description

Standard flow measuring device and multi-test bed flow consistency evaluation method Technical Field The invention relates to a flow measurement accuracy evaluation method, in particular to a standard flow measurement device and a multi-test-bed flow consistency evaluation method. Background In performing liquid engine surface tests, in situ calibration of liquid oxygen flow measurements is often required. However, the existing liquid oxygen flow measurement method is limited by the difference of test systems of different test benches, the difference of an in-situ calibration device and a flow measurement device and the individual difference of engines, and cannot carry out transverse comparison evaluation on the liquid oxygen flow measurement precision of each test bench. Therefore, a method for realizing the consistency evaluation of the flow of multiple test beds is needed. Disclosure of Invention The invention provides a standard flow measurement device and a multi-test-bed flow consistency evaluation method, which are used for solving the technical problem that the existing liquid oxygen flow measurement method is limited by the difference of different test bed systems, the difference of an in-situ calibration device and a flow measurement device and the individual difference of engines, and the liquid oxygen flow measurement precision of each test bed cannot be subjected to transverse comparison evaluation. In order to achieve the above purpose, the present invention adopts the following technical scheme: In one aspect, the present invention provides a standard flow measurement device comprising: a differential pressure pipe, which adopts a venturi pipe; the rectifying tube is arranged at the upstream of the differential pressure tube along the flow direction of the medium and adopts a porous pore plate structure; the pressure regulating pipe is arranged at the downstream of the differential pressure pipe along the medium flow direction and adopts a porous pore plate structure; And the pressure and temperature measuring units are respectively arranged on the differential pressure pipe, the rectifying pipe and the pressure regulating pipe and are used for measuring the pressure and the temperature at different positions in the differential pressure pipe, the rectifying pipe and the pressure regulating pipe. Further, the pressure and temperature measuring unit comprises a pressure measuring element and a temperature sensor, the pressure measuring element comprising a pressure sensor or a differential pressure sensor. Further, a plurality of pressure taking holes are formed in the pipe wall of the differential pressure pipe, an outer sleeve is sleeved outside the differential pressure pipe, a pressure stabilizing cavity is formed between the outer sleeve and the differential pressure pipe, pressure measuring elements corresponding to the pressure taking holes in number are arranged on the circumferential direction of the outer sleeve, and mounting points of the pressure measuring elements are staggered with the pressure taking holes. Furthermore, temperature sensors are arranged at the top of the differential pressure pipe and at 120-degree intervals in the circumferential direction. Further, the device further comprises: The heat insulation structure is sleeved outside the differential pressure pipe, the rectifying pipe and the pressure regulating pipe; And the measurement and control system is used for collecting data of the pressure and temperature measuring unit, and medium flow passing through the differential pressure pipe, the rectifying pipe and the pressure regulating pipe, and carrying out data processing. On the other hand, the invention provides a multi-test-bed flow consistency evaluation method based on the standard flow measurement device, which comprises the following steps: step 1, measuring and calibrating a standard flow measuring device, and determining a standard flow coefficient C of the standard flow measuring device; step 2, performing on-site in-situ calibration on the standard flow measuring device after metering calibration; And 3, carrying out liquid oxygen flow comparison evaluation on liquid oxygen tapping systems carried by different test benches by adopting a standard flow measuring device after in-situ calibration, so as to realize flow consistency evaluation of multiple test benches. Further, the specific operation of step 2 includes the following steps: the standard flow measuring device after measurement and calibration is arranged in a liquid oxygen tapping system pipeline of a 1# test bed, a sectional liquid level meter is arranged in the liquid oxygen tapping system pipeline of the 1# test bed, and the liquid oxygen flow passing through the standard flow measuring device is measured Monitoring temperature and pressure data corresponding to different parts of a differential pressure pipe, a rectifying pipe and a pressure regulating pipe in a standard flow measuring d