阅读说明：本技术 一种使用体积流量计现场标定质量流量的方法 (Method for calibrating mass flow on site by using volume flowmeter ) 是由 王飞 李先锋 史煜 赵芳 谢明伟 褚卫华 于 2021-08-16 设计创作，主要内容包括：本发明公开了一种使用体积流量计现场标定质量流量的方法,属于机电液及自动化技术应用领域；本发明在已构建的体积流量计现场标定装置上,通过确定时间内,对排放出的密度确定的标定液进行收集并称重,通过体积换算,并同步精确采集流量计电流信号,获得流量计在不同设定挤推压力下的体积流量和电流信号,拟合获得体积流量计的体积流量/电流标定公式；根据试验平台实际使用的液体燃烧剂密度,进行体积/质量换算,间接获得试验平台使用体积流量计监测燃烧剂的质量流量/电流标定公式,嵌入到测控系统中,实现液体燃烧剂质量流量的准确监测,确保平台试验过程的安全可控,满足实际工程应用。(The invention discloses a method for calibrating mass flow on site by using a volume flow meter, belonging to the field of application of electromechanical liquid and automation technology; on a constructed on-site calibration device of a volume flowmeter, the method collects and weighs calibration liquid with determined density in a determined time, obtains volume flow and current signals of the flowmeter under different set extrusion pushing pressures through volume conversion and synchronous and accurate acquisition of flowmeter current signals, and obtains a volume flow/current calibration formula of the volume flowmeter through fitting; according to the density of the liquid combustion agent actually used by the test platform, volume/mass conversion is carried out, a mass flow/current calibration formula for monitoring the combustion agent by using a volume flow meter by the test platform is indirectly obtained, and the calibration formula is embedded into a measurement and control system, so that the accurate monitoring of the mass flow of the liquid combustion agent is realized, the safety and the controllability of the test process of the platform are ensured, and the practical engineering application is met.)

1. A method of calibrating mass flow in situ using a volumetric flow meter, comprising: the method comprises the following steps:

s1, assembling calibration equipment, and selecting dry, pure and common high-pressure dry gas as extruding gas; selecting pure, density-determined and commonly-used liquid as calibration liquid; when the external environment is normal temperature and normal pressure, the chemical properties of the two are stable; calibrating the density Ds of the solution, wherein the unit is g/ml;

the calibration equipment comprises a squeezing and pushing gas cylinder group (1), a calibration liquid storage tank (8), a gas filling mechanism (25), a recovery tank (15) and an acquisition control system (16), wherein a gas outlet of the gas filling mechanism (25) is communicated with the interior of the squeezing and pushing gas cylinder group (1) through a gas filling pipeline (26); an outlet of the squeezing and pushing air bottle group (1) is communicated with the top of a calibration liquid storage tank (8) through an air conveying pipeline (3), the bottom of one side of the calibration liquid storage tank (8) is communicated with an infusion pipeline (11), one end of the infusion pipeline (11) is vertically arranged downwards, a recovery tank (15) is placed below one end of the infusion pipeline (11), and the recovery tank (15) is placed on a weighing tray of an electronic weighing scale (24);

an air pressure sensor I (2) is arranged at the top of the squeezing gas cylinder group (1);

a manual pressure reducing valve (4), an air pressure meter I (5), an air pressure sensor II (6) and an air electromagnetic valve (7) are sequentially arranged on the air transmission pipeline (3);

an air pressure sensor III (9) and an air pressure gauge II (10) are mounted at the top of the calibration liquid storage tank (8);

the infusion pipeline (11) is sequentially provided with a liquid electromagnetic valve (12), a volume flow meter (13) and a liquid discharge electromagnetic valve (14);

the signal output ends of the air pressure sensor I (2), the air pressure sensor II (6), the air pressure sensor III (9), the volume flow meter (13) and the weighing electronic scale (24) are respectively and electrically connected with the signal input end of the acquisition control system (16) through signal cables, and the control output end of the acquisition control system (16) is respectively and electrically connected with the electric control ends of the gas electromagnetic valve (7), the liquid electromagnetic valve (12), the weighing electronic scale (24) and the liquid discharge electromagnetic valve (14) through control cables;

s2, inflating and pressurizing the pressure of the squeezing and pushing gas cylinder set (1) to a working pressure Pw which is more than or equal to 10MPa, so that the working pressure of high-pressure drying gas serving as squeezing and pushing gas in the squeezing and pushing gas cylinder set (1) is Pw which is more than or equal to 10 MPa; adding the calibration liquid into a calibration liquid storage tank (8), wherein the volume ratio of the filled calibration liquid to the volume of the calibration liquid storage tank (8) is R, and R is more than or equal to 0.5 and less than or equal to 0.8;

s3, adjusting a manual pressure reducing valve (4), and initially adjusting the squeezing pressure Ps of the gas transmission pipeline (3) after the manual pressure reducing valve (4) to a filling pressure Pf, wherein Ps is more than or equal to 0.0MPa and less than or equal to 10.0MPa, and Pf is more than or equal to 0.2 MPa and less than or equal to 0.5 MPa;

s4, opening a gas electromagnetic valve (7) by an acquisition control system (16), and inflating and pressurizing a calibration liquid storage tank (8) to a filling pressure Pf; opening a liquid electromagnetic valve (12) and a liquid discharge electromagnetic valve (14), and filling the infusion pipeline (11) until a calibration liquid flows to a recovery tank (15); then, closing the liquid discharge electromagnetic valve (14), the liquid electromagnetic valve (12) and the gas electromagnetic valve (7);

s5, determining the total index point number n, wherein n is an integer;

s6, setting the sequence of the current calibration points as k, and peeling and returning to zero the weighing electronic scale (24) with the recovery tank (15) placed; k is a positive integer, the number of k is increased from 1 in sequence, and k is less than or equal to n;

s7, adjusting a manual pressure reducing valve (4), and adjusting the extrusion pressure Ps to the set pressure Ps (k) of the current calibration point, wherein Ps (k) is more than or equal to 2.0 MPa and less than or equal to 10.0 MPa;

s8, setting the sampling time T (k) and the sampling frequency f (k) of the calibration point in the acquisition control system (16), wherein T (k) is more than or equal to 5S and less than or equal to 30S, f (k) is more than or equal to 10Hz and less than or equal to 50Hz, and T (k) and f (k) are integers;

s9, opening the electromagnetic valve (12) for liquid in advance;

s10, the acquisition control system (16) automatically opens the gas solenoid valve (7) and the liquid discharge solenoid valve (14), starts to discharge and collect the calibration liquid of the calibration point, and simultaneously records the current signal array Ik of the volume flowmeter (13) of the calibration point; the system is accurately timed, the sampling time T (k) is over, the collection control system (16) automatically closes the liquid discharge electromagnetic valve (14), and the discharge and collection of the calibration liquid of the calibration point are over; the collection control system (16) closes the liquid electromagnetic valve (12) and the gas electromagnetic valve (7); ik is a one-dimensional array containing f (k) · T (k) data, and each value of the array is in the range of [4, 20], and the unit is mA;

s11, weighing by a weighing electronic scale (24) to obtain the weight Ms (k) of the calibration point calibration solution; calculating to obtain the volume L (k) = Ms (k)/Ds of the calibration liquid collected by the calibration point according to the density Ds of the calibration liquid; calculating the volume flow rate fv (k) = L (k)/T (k) of the volume flowmeter (13) for obtaining the calibration point according to the acquisition time T (k); calculating and obtaining the average current Ia (k) = (Ik [0] + Ik [1] + … … + Ik [ f (k) · T (k) -1)/(f (k) · T (k)) of the current calibration point volume flowmeter (13) through a current signal array Ik; units of Ms (k) are g, units of L (k) are ml, units of fv (k) are ml/s, units of Ia (k) are mA;

s12, repeating S6-S11, setting squeezing pressure Ps (k) of different calibration point sequences k by adjusting the manual pressure reducing valve (4), and obtaining the volume flow fv (k) and the average current Ia (k) of the volume flow meter (13) until obtaining the volume flow and the average current data of the volume flow meter (13) of all the calibration points;

s13, carrying out data fitting by using the obtained volume flow rates Fv (1), Fv (2), … …, Fv (n) of the volume flow meter (13) and corresponding average currents Ia (1), Ia (2), … … and Ia (n) to obtain a volume flow rate/current calibration formula Fv = G (I) of the volume flow meter (13); fv is the volume flow measurement value of the volume flowmeter (13) with the unit of ml/s, and I is the current measurement value of the volume flowmeter (13) with the unit of mA; g is a calibration formula functional relation;

s14, indirectly obtaining a mass flow/current calibration formula Fm = Df · Fv = Df · G (I) of the combustion agent monitored by the test platform through a volume flow meter (13) according to the density Df of the combustion agent actually used by the test platform, namely Fm = Df · G (I); df unit is g/ml; fm is a test platform combustion agent mass flow measurement value, and the unit is g/s; i is a current measurement value of the test platform volume flowmeter (13) and the unit is mA;

s15, embedding the mass flow/current calibration formula Fm = Df G (I) into a test platform measurement and control system, and monitoring the mass flow of the combustion agent in the test process of the test platform in real time.

2. The method for calibrating mass flow in situ using a volumetric flowmeter of claim 1, wherein in step S1, dry nitrogen N is selected as the high pressure dry gas₂Distilled water H is selected as the extruding gas₂O liquid as calibration liquid and distilled water H₂The O density is determined to be 1 g/ml; when the external environment is normal temperature and normal pressure, nitrogen N is dried under high pressure₂And distilled water H₂O does not generate chemical reaction, and the accuracy of the calibration result is ensured.

3. The method for calibrating mass flow in situ by using a volume flow meter according to claim 1, wherein the signal output terminal of the air pressure sensor I (2) is connected with the collection control system (16) through a signal cable I (17), the signal output terminal of the air pressure sensor II (6) is connected with the collection control system (16) through a signal cable II (18), the electric control terminal of the gas solenoid valve (7) is connected with the collection control system (16) through a control cable I (19), the signal output terminal of the air pressure sensor III (9) is connected with the collection control system (16) through a signal cable III (20), the electric control terminal of the liquid solenoid valve (12) is connected with the collection control system (16) through a control cable II (21), and the signal output terminal of the volume flow meter (13) is connected with the collection control system (16) through a signal cable IV (22), the electric control end of the liquid discharge electromagnetic valve (14) is connected with an acquisition control system (16) through a control cable III (23), and the acquisition control system (16) comprises a PLC (programmable logic controller).

4. The method for on-site calibration of mass flow rate by using a volumetric flow meter according to claim 1, characterized in that the gas filling means (25) is a nitrogen production pressurizing device, and the pressure in the squeeze gas cylinder set (1) is maintained between 10.0Mpa and 10.5Mpa by the gas filling means (25).

Technical Field

The invention relates to the technical field of electromechanical liquid and automation, in particular to a method for calibrating mass flow on site by using a volume flow meter.

Background

In order to ensure that the mixing ratio of the combustion agent and the combustion improver is within the design range in the test process of a certain high-temperature high-pressure gas generator test platform and simultaneously ensure the safety and controllability of the test process of the platform, the mass flow of the combustion agent needs to be monitored in real time. Therefore, on the basis of a volume flowmeter calibration device constructed on site, a method for calibrating mass flow on site by using a volume flowmeter is provided, and mass flow of a combustion agent is calibrated on site by using the volume flowmeter.

A method for calibrating mass flow in situ by using a volume flowmeter is based on the following basic idea: collecting and weighing discharged calibration liquid (density determination) within a determined time, carrying out volume conversion, synchronously and accurately collecting flowmeter current signals, obtaining volume flow and current signals of the flowmeter under different set extrusion pressure, and fitting to obtain a volume flow/current calibration formula of the volume flowmeter; according to the density (density determination) of the liquid combustion agent actually used by the test platform, carrying out volume/mass conversion, indirectly obtaining a mass flow/current calibration formula of the combustion agent monitored by the test platform through a volume flow meter, and embedding the calibration formula into a measurement and control system to realize accurate monitoring of the mass flow of the liquid combustion agent of the test platform; therefore, the safety and controllability of the platform test process are ensured.

Disclosure of Invention

The present invention is directed to a method for calibrating mass flow in situ using a volumetric flow meter, which overcomes the above-mentioned problems of the prior art.

The technical scheme of the invention is realized as follows:

a method of calibrating mass flow in situ using a volumetric flow meter, comprising the steps of:

s1, assembling calibration equipment, and selecting dry, pure and common high-pressure dry gas as extruding gas; selecting pure, density-determined and commonly-used liquid as calibration liquid; when the external environment is normal temperature and normal pressure, the chemical properties of the two are stable; calibrating the density Ds of the solution, wherein the unit is g/ml;

the calibration equipment comprises a squeezing and pushing gas cylinder group, a calibration liquid storage tank, a gas filling mechanism, a recovery tank and an acquisition control system, wherein a gas outlet of the gas filling mechanism is communicated with the interior of the squeezing and pushing gas cylinder group through a gas filling pipeline; an outlet of the squeezing and pushing air bottle group is communicated with the top of a calibration liquid storage tank through an air conveying pipeline, the bottom of one side of the calibration liquid storage tank is communicated with an infusion pipeline, one end of the infusion pipeline is vertically and downwards arranged, a recovery tank is arranged below one end of the infusion pipeline, and the recovery tank is arranged on a weighing tray of the weighing electronic scale;

the top of the squeezing gas cylinder group is provided with an air pressure sensor I;

a manual pressure reducing valve, a barometer I, a barometer II and a pneumatic solenoid valve are sequentially arranged on the gas transmission pipeline;

the top of the calibration liquid storage tank is provided with an air pressure sensor III and an air pressure gauge II;

the liquid conveying pipeline is sequentially provided with a liquid electromagnetic valve, a volume flow meter and a liquid discharging electromagnetic valve;

the signal output ends of the air pressure sensor I, the air pressure sensor II, the air pressure sensor III, the volume flow meter and the weighing electronic scale are respectively and electrically connected with the signal input end of the acquisition control system through signal cables, and the control output end of the acquisition control system is respectively and electrically connected with the electric control ends of the gas electromagnetic valve, the liquid electromagnetic valve, the weighing electronic scale and the liquid discharging electromagnetic valve through control cables;

s2, inflating and pressurizing the squeezing and pushing gas cylinder group to a working pressure Pw which is more than or equal to 10MPa, so that the working pressure of high-pressure drying gas serving as squeezing and pushing gas in the squeezing and pushing gas cylinder group is Pw which is more than or equal to 10 MPa; adding a calibration liquid into a calibration liquid storage tank, wherein the volume ratio of the filled calibration liquid to the volume of the calibration liquid storage tank is R, and R is more than or equal to 0.5 and less than or equal to 0.8;

s3, adjusting a manual pressure reducing valve, and preliminarily adjusting the squeezing pressure Ps of the gas transmission pipeline behind the manual pressure reducing valve to a filling pressure Pf, wherein Ps is more than or equal to 0.0MPa and less than or equal to 10.0MPa, and Pf is more than or equal to 0.2 MPa and less than or equal to 0.5 MPa;

s4, opening a gas electromagnetic valve by the acquisition control system, and inflating and pressurizing the calibration liquid storage tank to a filling pressure Pf; opening a liquid electromagnetic valve and a liquid discharge electromagnetic valve, and filling the infusion pipeline until a calibration liquid flows to a recovery tank; then, closing the liquid discharge electromagnetic valve, the liquid electromagnetic valve and the gas electromagnetic valve;

s5, determining the total index point number n, wherein n is an integer;

s6, setting the sequence of the current calibration points as k, and peeling and zeroing the weighing electronic scale with the recovery tank; k is a positive integer, the number of k is increased from 1 in sequence, and k is less than or equal to n;

s7, adjusting a manual pressure reducing valve, and adjusting the extrusion pressure Ps to the set pressure Ps (k) of the current calibration point, wherein Ps (k) is more than or equal to 2.0 MPa and less than or equal to 10.0 MPa;

s8, setting the sampling time T (k) and the sampling frequency f (k) of the calibration point in the acquisition control system, wherein T (k) is more than or equal to 5S and less than or equal to 30S, f (k) is more than or equal to 10Hz and less than or equal to 50Hz, and T (k) and f (k) are integers;

s9, opening the electromagnetic valve for liquid in advance;

s10, the acquisition control system automatically opens the gas solenoid valve and the liquid discharge solenoid valve, starts to discharge and collect the calibration liquid of the calibration point, and simultaneously records the current signal array Ik of the volume flowmeter of the calibration point; the system accurately times, the sampling time T (k) is over, the collection control system automatically closes the liquid discharge electromagnetic valve, and the discharge and collection of the calibration liquid of the calibration point are over; the collection control system closes the electromagnetic valve for liquid and the electromagnetic valve for gas; ik is a one-dimensional array containing f (k) · T (k) data, and each value of the array is in the range of [4, 20], and the unit is mA;

s11, weighing by a weighing electronic scale to obtain the weight Ms (k) of the calibration point calibration liquid at the time; calculating to obtain the volume L (k) = Ms (k)/Ds of the calibration liquid collected by the calibration point according to the density Ds of the calibration liquid; calculating the volume flow fv (k) = L (k)/T (k) of the volume flowmeter of the calibration point according to the acquisition time T (k); calculating to obtain the average current Ia (k) = (Ik [0] + Ik [1] + … … + Ik [ f (k) · T (k) -1)/(f (k) · T (k)) of the calibrated point volume flowmeter; units of Ms (k) are g, units of L (k) are ml, units of fv (k) are ml/s, units of Ia (k) are mA;

s12, repeating S6-S11, setting extrusion pressure Ps (k) of different calibration point sequences k by adjusting a manual pressure reducing valve, and obtaining the volume flow fv (k) and the average current Ia (k) of the volume flow meter until obtaining the volume flow and the average current data of the volume flow meter of all the calibration points;

s13, carrying out data fitting by using the obtained volume flow rates Fv (1), Fv (2), … …, Fv (n) and corresponding average currents Ia (1), Ia (2), … … and Ia (n) of the volume flow meter to obtain a volume flow rate/current calibration formula Fv = G (I) of the volume flow meter; fv is the volume flow measurement value of the volume flowmeter, and the unit is ml/s, I is the current measurement value of the volume flowmeter, and the unit is mA; g is a calibration formula functional relation;

s14, indirectly obtaining a mass flow/current calibration formula Fm = Df · Fv = Df · G (I) of the combustion agent monitored by the test platform through a volume flow meter according to the density Df of the combustion agent actually used by the test platform, namely Fm = Df · G (I); df unit is g/ml; fm is a test platform combustion agent mass flow measurement value, and the unit is g/s; i is a current measurement value of the volume flowmeter of the test platform, and the unit is mA;

s15, embedding the mass flow/current calibration formula Fm = Df G (I) into a test platform measurement and control system, and monitoring the mass flow of the combustion agent in the test process of the test platform in real time.

Further, in step S1, high pressure dry nitrogen N is selected₂Distilled water H is selected as the extruding gas₂O liquid as calibration liquid and distilled water H₂The O density is determined to be 1 g/ml; when the external environment is normal temperature and normal pressure, high pressure nitrogen N₂And distilled water H₂O does not generate chemical reaction, and the accuracy of the calibration result is ensured.

Further, the signal output part of the air pressure sensor I is connected with the acquisition control system through a signal cable I, the signal output part of the air pressure sensor II is connected with the acquisition control system through a signal cable II, the electric control end of the air electromagnetic valve is connected with the acquisition control system through a control cable I, the signal output part of the air pressure sensor III is connected with the acquisition control system through a signal cable III, the electric control end of the liquid electromagnetic valve is connected with the acquisition control system through the control cable II, the signal output part of the volume flow meter is connected with the acquisition control system through a signal cable IV, the electric control end of the liquid discharge electromagnetic valve is connected with the acquisition control system through the control cable III, and the acquisition control system comprises a PLC (programmable logic controller).

Furthermore, the gas filling mechanism is a nitrogen making pressurizing device, and the pressure in the extrusion gas cylinder set is maintained between 10.0MPa and 10.5MPa through the gas filling mechanism.

The invention has the beneficial effects that:

1. the method for calibrating mass flow on site by using the volume flow meter provided by the invention realizes the on-site calibration of mass flow of the combustion agent of a certain high-temperature high-pressure gas generator test platform by using the volume flow meter on the constructed on-site calibration device of the volume flow meter, and meets the requirement of monitoring the mass flow of the combustion agent in real time in the test process of the platform;

2. according to the method for calibrating the mass flow on site by using the volume flow meter, provided by the invention, dry, pure and common gas is selected as the extruding gas, pure, density-determined and common liquid is selected as the calibration liquid, and the chemical properties of the pure, pure and common liquid are stable under normal temperature and normal pressure, so that the calibration process and the result are feasible and credible;

3. the invention provides a method for calibrating mass flow on site by using a volume flowmeter, which obtains accurate volume flow and current of the flowmeter through strict time control, mass volume conversion and signal average processing; the setting of the extrusion pushing pressure in a wide range is realized through manual adjustment, so that a series of volume flow and corresponding current values of the flowmeter are obtained, and a volume flow/current calibration formula of the flowmeter is obtained through fitting;

4. according to the method for calibrating the mass flow on site by using the volume flow meter, provided by the invention, a mass flow/current calibration formula for monitoring the combustion agent by using the volume flow meter on the test platform is obtained through the calculation of the volume flow and the density of the combustion agent, and is supplied to a platform measurement and control system for use, so that the test safety of the platform is further ensured.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a flow chart of a method for calibrating mass flow in situ using a volumetric flow meter according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a field calibration apparatus for a volumetric flowmeter according to an embodiment of the invention.

In the figure:

1. pushing the air bottle group; 2. an air pressure sensor I; 3. a gas transmission pipeline; 4. a manual pressure reducing valve; 5. a barometer I; 6. an air pressure sensor II; 7. a gas solenoid valve; 8. a calibration liquid storage tank; 9. an air pressure sensor III; 10. a barometer II; 11. a transfusion pipeline; 12. a hydraulic solenoid valve; 13. a volumetric flow meter; 14. a liquid discharge electromagnetic valve; 15. a recovery tank; 16. an acquisition control system; 17. a signal cable I; 18. a signal cable II; 19. a control cable I; 20. a signal cable III; 21. a control cable II; 22. a signal cable IV; 23. a control cable III; 24. weighing an electronic scale; 25. a gas adding mechanism; 26. and a gas adding pipeline.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the embodiments given herein are intended to be within the scope of the present invention.

The first embodiment is as follows:

in accordance with an embodiment of the present invention,

referring to fig. 1, a method for calibrating mass flow in situ using a volumetric flow meter includes the steps of:

s1, assembling calibration equipment, and selecting dry, pure and common high-pressure dry gas as extruding gas; selecting pure, density-determined and commonly-used liquid as calibration liquid; when the external environment is normal temperature and normal pressure, the chemical properties of the two are stable; calibrating the density Ds of the solution, wherein the unit is g/ml;

as shown in fig. 2, the calibration device comprises a squeeze gas bottle group 1, a calibration liquid storage tank 8, a gas filling mechanism 25, a recovery tank 15 and an acquisition control system 16, wherein a gas outlet of the gas filling mechanism 25 is communicated with the interior of the squeeze gas bottle group 1 through a gas filling pipeline 26; an outlet of the squeezing and pushing air bottle group 1 is communicated with the top of a calibration liquid storage tank 8 through an air conveying pipeline 3, the bottom of one side of the calibration liquid storage tank 8 is communicated with an infusion pipeline 11, one end of the infusion pipeline 11 is vertically and downwards arranged, a recovery tank 15 is arranged below one end of the infusion pipeline 11, and the recovery tank 15 is arranged on a weighing tray of a weighing electronic scale 24;

wherein, an air pressure sensor I2 is arranged at the top of the squeezing air bottle group 1; the gas transmission pipeline 3 is sequentially provided with a manual pressure reducing valve 4, a barometer I5, a pressure sensor II6 and a gas electromagnetic valve 7; the top of the calibration liquid storage tank 8 is provided with an air pressure sensor III9 and an air pressure gauge II 10; the infusion pipeline 11 is sequentially provided with a liquid electromagnetic valve 12, a volume flow meter 13 and a liquid discharge electromagnetic valve 14;

the signal output ends of the air pressure sensor I2, the air pressure sensor II6, the air pressure sensor III9, the volume flow meter 13 and the weighing electronic scale 24 are respectively and electrically connected with the signal input end of the acquisition control system 16 through signal cables, and the control output end of the acquisition control system 16 is respectively and electrically connected with the electric control ends of the air electromagnetic valve 7, the liquid electromagnetic valve 12, the weighing electronic scale 24 and the liquid discharge electromagnetic valve 14 through control cables;

s2, inflating and pressurizing the pressure of the squeezing and pushing gas cylinder set 1 to a working pressure Pw which is more than or equal to 10MPa, so that the working pressure of high-pressure drying gas serving as squeezing and pushing gas in the squeezing and pushing gas cylinder set 1 is Pw which is more than or equal to 10 MPa; adding a calibration solution into a calibration solution storage tank 8, wherein the volume ratio of the filled calibration solution to the calibration solution storage tank 8 is R, and R is more than or equal to 0.5 and less than or equal to 0.8;

s3, adjusting the manual pressure reducing valve 4, and initially adjusting the squeezing pressure Ps of the gas transmission pipeline 3 after the manual pressure reducing valve 4 to a filling pressure Pf, wherein Ps is more than or equal to 0.0MPa and less than or equal to 10.0MPa, and Pf is more than or equal to 0.2 MPa and less than or equal to 0.5 MPa;

s4, opening the gas electromagnetic valve 7 by the acquisition control system 16, and inflating and pressurizing the calibration liquid storage tank 8 to a filling pressure Pf; opening the liquid electromagnetic valve 12 and the liquid discharge electromagnetic valve 14, and filling the infusion pipeline 11 until calibration liquid flows to the recovery tank 15; then, the liquid discharge electromagnetic valve 14, the liquid electromagnetic valve 12 and the gas electromagnetic valve 7 are closed; wherein, S2-S4 are debugging preparation stages;

s5, determining the total index point number n, wherein n is an integer;

s6, setting the sequence of the current calibration points as k, and peeling and zeroing the weighing electronic scale 24 with the recovery tank 15; k is a positive integer, the number of k is increased from 1 in sequence, and k is less than or equal to n;

s7, adjusting a manual pressure reducing valve 4, and adjusting the extrusion pressure Ps to the set pressure Ps (k) of the current calibration point, wherein Ps (k) is more than or equal to 2.0 MPa and less than or equal to 10.0 MPa;

s8, setting the sampling time T (k) and the sampling frequency f (k) of the calibration point in the acquisition control system 16, wherein T (k) is more than or equal to 5S and less than or equal to 30S, f (k) is more than or equal to 10Hz and less than or equal to 50Hz, and T (k) and f (k) are integers;

s9, opening the electromagnetic valve 12 for liquid in advance;

s10, the acquisition control system 16 automatically opens the gas solenoid valve 7 and the liquid discharge solenoid valve 14, starts the discharge and collection of the calibration liquid of the calibration point, and simultaneously records the current signal array Ik of the volume flowmeter 13 of the calibration point; the system is accurately timed, the sampling time T (k) is over, the collection control system 16 automatically closes the liquid discharge electromagnetic valve 14, and the discharge and collection of the calibration liquid of the calibration point are over; the acquisition control system 16 closes the electromagnetic valve 12 for liquid and the electromagnetic valve 7 for gas; ik is a one-dimensional array containing f (k) · T (k) data, and each value of the array is in the range of [4, 20], and the unit is mA;

s11, weighing by the electronic weighing scale 24 to obtain the weight Ms (k) of the calibration point calibration liquid at the time; calculating to obtain the volume L (k) = Ms (k)/Ds of the calibration liquid collected by the calibration point according to the density Ds of the calibration liquid; calculating the volume flow fv (k) = l (k)/t (k) of the volume flowmeter 13 for obtaining the calibration point at this time according to the acquisition time t (k); calculating to obtain an average current ia (k) = (Ik [0] + Ik [1] + … … + Ik [ f (k) · t (k) -1)/(f (k) · t (k)) of the present calibrated point volumetric flowmeter 13 through a current signal array Ik; units of Ms (k) are g, units of L (k) are ml, units of fv (k) are ml/s, units of Ia (k) are mA;

s12, repeating S6-S11, setting squeezing pressure Ps (k) of different calibration point sequences k by adjusting the manual pressure reducing valve 4, and obtaining the volume flow fv (k) and the average current Ia (k) of the volume flow meter 13 until obtaining the volume flow and the average current data of the volume flow meter 13 of all the calibration points;

s13, performing data fitting by using the obtained volume flow rates Fv (1), Fv (2), … …, Fv (n) and the corresponding average currents Ia (1), Ia (2), … …, Ia (n) of the volume flow meter 13 to obtain a volume flow rate/current calibration formula Fv = g (i) of the volume flow meter 13; fv is the volume flow measurement value of the volume flowmeter 13, and the unit is ml/s, I is the current measurement value of the volume flowmeter 13, and the unit is mA; g is a calibration formula functional relation;

s14, indirectly obtaining a mass flow/current calibration formula Fm = Df · Fv = Df · G (I) of the combustion agent monitored by the test platform by using the volume flow meter 13 according to the density Df of the combustion agent actually used by the test platform, namely Fm = Df · G (I); df unit is g/ml; fm is a test platform combustion agent mass flow measurement value, and the unit is g/s; i is a current measurement value of the test platform volume flowmeter 13, and the unit is mA;

s15, embedding the mass flow/current calibration formula Fm = Df G (I) into a test platform measurement and control system, and monitoring the mass flow of the combustion agent in the test process of the test platform in real time.

Specifically, when the system is implemented, the signal output end of the air pressure sensor I2 is connected with the acquisition control system 16 through a signal cable I17, the signal output end of the air pressure sensor II6 is connected with the acquisition control system 16 through a signal cable II18, the electric control end of the air electromagnetic valve 7 is connected with the acquisition control system 16 through a control cable I19, the signal output end of the air pressure sensor III9 is connected with the acquisition control system 16 through a signal cable III20, the electric control end of the liquid electromagnetic valve 12 is connected with the acquisition control system 16 through a control cable II21, the signal output end of the volume flow meter 13 is connected with the acquisition control system 16 through a signal cable IV22, the electric control end of the liquid discharge electromagnetic valve 14 is connected with the acquisition control system 16 through a control cable III23, and the acquisition control system 16 comprises a PLC controller.

In the above embodiment, the gas filling mechanism 25 is a nitrogen-making pressurizing device, so as to ensure that the pressure in the squeeze gas cylinder set 1 is maintained between 10.0Mpa and 10.5 Mpa.

The embodiment is applied to a test platform of a certain high-temperature high-pressure gas generator, the actually used combustion agent of the test platform is industrial alcohol, and the detailed flow is as follows based on a volume flow meter field calibration device:

s1, selecting high-pressure dry nitrogen (N)₂) Distilled water (H) was selected as the pushing gas₂O) liquid is used as calibration liquid, and the chemical properties of the liquid and the calibration liquid are stable when the external environment is normal temperature and normal pressure; the density of distilled water is 1 g/ml;

s2, pressurizing the working pressure Pw of the squeeze gas cylinder group 1 to 10.5 MPa; distilled water (H)₂O) is added into a calibration liquid storage tank 8, the volume of the calibration liquid storage tank 8 is 200000ml, the volume ratio R of the added distilled water to the volume of the calibration liquid storage tank 8 is 0.7, namely the added distilled water is 140000 ml;

s3, manually adjusting the manual pressure reducing valve 4, and initially adjusting the squeezing pressure Ps (namely the pressure behind the manual pressure reducing valve 4) to the filling pressure Pf =0.3 MPa;

s4, opening the electromagnetic valve 7 for gas by the acquisition control system 16, and inflating and pressurizing the calibration liquid storage tank 8 to a filling pressure of 0.3 MPa; opening the liquid solenoid valve 12 and the liquid discharge solenoid valve 14 to fill the liquid delivery pipe 11 until distilled water (H) is present₂O) to the recovery tank 15; then, the liquid discharge electromagnetic valve 14, the liquid electromagnetic valve 12 and the gas electromagnetic valve 7 are closed; in the operation of step S4, the calibration liquid collected at the first calibration point is ensured to eliminate errors of the part of the infusion pipeline 11 by filling the infusion pipeline 11; in actual operation, the data of the first index point can be discarded;

s5, determining the total number of the calibration points to be 6;

s6, setting the sequence of the current calibration points to be 1, and peeling and zeroing the weighing electronic scale 24 with the recovery tank 15;

s7, adjusting a manual pressure reducing valve 4, and adjusting the extrusion pressure Ps to the current set point pressure Ps (1), wherein Ps (1) =2.5 MPa;

s8, setting the current calibration point sampling time T (1) and sampling frequency f (1) in the acquisition control system 16, where T (1) =10S and f (1) =20 Hz;

s9, opening the electromagnetic valve 12 for liquid in advance;

s10, starting calibration, the acquisition control system 16 automatically opens the gas solenoid valve 7 and the liquid discharge solenoid valve 14 to start the calibration of the point distilled water (H)₂O) discharging and collecting, and simultaneously recording a current signal array I1 of the volume flowmeter 13 of the calibration point; the system is accurately timed, the sampling time T (1) is over, the collection control system 16 automatically closes the liquid discharge electromagnetic valve 14, and the calibration point distilled water (H) is over₂O) discharging and collecting; the acquisition control system 16 closes the electromagnetic valve 12 for liquid and the electromagnetic valve 7 for gas; i1 is a one-dimensional array containing f (1) · T (1) =20 · 10=200 data, each value of the array is [4, 20 = 20%]Within the range, in mA;

s11, weighing by the electronic weighing scale 24 to obtain the distilled water (H) collected at the calibration point₂O) weight Ms (1) =10644 g; according to distilled water (H)₂O) density of 1g/ml, and calculating to obtain the distilled water (H) collected at the calibration point₂O) volume L (1) = 10644/1=10644 ml; calculating to obtain the volume flow Fv (1) = 10644/10=1064.4ml/s of the calibration point volume flowmeter 13 according to the acquisition time 10 s; calculating to obtain the average current Ia (1) =8.060mA of the current calibration point volume flowmeter 13 through the current signal array I1;

s12, repeating S6-S11, setting extrusion pushing pressures Ps (k) when the sequence k of the calibration points is sequentially 2, 3, 4, 5 and 6 by adjusting the manual pressure reducing valve 4, wherein Ps (2) =3.5MPa, Ps (3) =4.5MPa, Ps (4) =5.5MPa, Ps (6) =6.5MPa and Ps (6) =7.5MPa respectively; under different extrusion pressure working conditions, the volume flow rates corresponding to the flow meters are respectively Fv (2) =1495.7ml/s, Fv (3) =1923ml/s, Fv (4) =2350.3 ml/s, Fv (5) =2777.7 ml/s and Fv (6) =3205 ml/s, and the average currents corresponding to the volume flow meters 13 are respectively Ia (2) =9.684mA, Ia (3) = 11.308mA, Ia (4) =12.932mA, Ia (5) =14.556mA and Ia (6) = 16.181 mA;

s13, performing data fitting by using the obtained volume flow rates Fv (1), Fv (2), … … and Fv (6) of the volume flow meter 13 and corresponding average currents Ia (1), Ia (2), … … and Ia (6), and finally obtaining a volume flow rate/current calibration formula Fv = 263.15. I-1052.5 of the flow meter; in the formula: fv is the volume flow measurement value of the volume flow meter 13, and the unit is ml/s; i is a current measurement value of the volume flowmeter 13 and has a unit of mA;

s14, obtaining a calibration formula Fm = Df · Fv =0.8 · (263.15 · I-1052.5) of the test platform for monitoring the mass flow rate/current of the alcohol by using the volume flowmeter 13 according to the density Df (0.8 g/ml) of the industrial alcohol actually used as the combustion agent of the test platform, namely Fm = 210.5 · I-842; fm is a mass flow measurement value of the alcohol of the test platform, and the unit is g/s; i is a current measurement value of the test platform volume flowmeter 13, and the unit is mA;

s15, embedding a calibration formula Fm = 210.5. I-842 of mass flow/current into a test platform measurement and control system, and monitoring the mass flow of alcohol in the test process in real time.

In summary, with the above technical solution of the present invention,

the method for calibrating mass flow on site by using the volume flow meter provided by the invention realizes the on-site calibration of mass flow of the combustion agent of a certain high-temperature high-pressure gas generator test platform by using the volume flow meter on the constructed on-site calibration device of the volume flow meter, and meets the requirement of monitoring the mass flow of the combustion agent in real time in the test process of the platform; dry, pure and common high-pressure dry gas is selected as the extruding gas, pure, density-determined and common liquid is selected as the calibration liquid, and the chemical properties of the dry, pure and common high-pressure dry gas and the pure, density-determined and common liquid are stable at normal temperature and normal pressure, so that the calibration process and the result are feasible and credible; accurate volume flow and current of the flowmeter are obtained through strict time control, mass volume conversion and signal average processing; the setting of the extrusion pushing pressure in a wide range is realized through manual adjustment, so that a series of volume flow and corresponding current values of the flowmeter are obtained, and a volume flow/current calibration formula of the flowmeter is obtained through fitting; through the calculation of the volume flow and the density of the combustion agent, a mass flow/current calibration formula for monitoring the combustion agent by using a volume flow meter on the test platform is obtained and is used by a platform measurement and control system, so that the test safety of the platform is ensured.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.