CN110470569A - A kind of capillary pipeline vapour lock measuring device and measuring method - Google Patents
A kind of capillary pipeline vapour lock measuring device and measuring method Download PDFInfo
- Publication number
- CN110470569A CN110470569A CN201910830824.4A CN201910830824A CN110470569A CN 110470569 A CN110470569 A CN 110470569A CN 201910830824 A CN201910830824 A CN 201910830824A CN 110470569 A CN110470569 A CN 110470569A
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- pipeline
- capillary pipeline
- pressure
- vapour lock
- tested
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N7/00—Analysing materials by measuring the pressure or volume of a gas or vapour
Abstract
The invention discloses a kind of capillary pipeline vapour lock measuring device and measuring method.The present invention includes two-stage tandem loop pressure-stabilizing gas source, measurement module, hardware system and computer.High accuracy and stability air pressure are provided by two-stage tandem loop pressure-stabilizing gas source；By the temperature of measurement module measurement capillary pipeline input terminal and output end, air pressure and pass through the flow of capillary pipeline, piping connection can be installed the influence flowed to gas in pipeline with sensor and minimized by the connector of independent design, improve the precision of measurement result；Closed-loop control, the adjusting of loine pressure and the transmission of sensing data of two-stage tandem loop pressure-stabilizing gas source are realized by hardware system；Vapour lock value is calculated according to formula R=λ ρ l/A by computer program, after completing one-shot measurement, data is saved and draws the characteristic curve of vapour lock under different input air pressures, while vapour lock characteristic can be analyzed.
Description
Technical field
The present invention relates to analysis and survey control technology fields, more particularly, to a kind of capillary pipeline vapour lock measuring device and
Measurement method.
Background technique
In Ultra-precision Turning and ultraprecise detection technique field, either Precision Machining or measuring instrument, all to machinery
Part proposes very harsh requirement.It was verified that gas-static lubrication technology has, speed is fast, precision is high, friction damage
Consume small, high-low temperature resistant and resistance to atomic radiation, the remarkable advantages such as pollution-free or of low pollution, the service life is long, structure is simple.However, gas
That there are bearing capacitys is low for hydrostatic lubrication technology, rigidity is small and the significant technology issues such as stability is poor.Gas-static flow controller is real
The core component of existing gas-static lubrication technology, thus correctly and reasonably choose and calculate the structure of gas-static flow controller with
Parameter is essential important content in the design of gas-static system.
Tradition mainly uses theoretical calculation, numerical value imitative the research of gas-static flow controller bearing capacity, rigidity and stability
The methods of true and Germicidal efficacy, however these methods the disadvantages of there are computationally intensive, simulation time is long, flexibility is poor.In recent years,
For research pipeline in fluid some motion state problems, many scholars by pressure, flow and the circuit in pipeline voltage,
Electric current is associated, establishes the equivalent-circuit model of pipe-line system, then realizes that simplifying for important parameter calculates, this analogy is especially
It is used widely in hydraulic system.Successful application based on equivalent-circuit model in incompressible fluid system, thus
It is necessary to study the equivalent-circuit models of compressible fluid system.By establishing the equivalent-circuit model of gas-static flow controller,
Side more easy and with degree of precision is provided for the calculating of the bearing capacity of gas-static flow controller, rigidity and stability
Method.
Tradition is distributed the foundation of gas-static flow controller equivalent-circuit model primarily directed to gas film pressure, is not considering
In the case where starting and stopping two transient processes, vapour lock is equivalent to linear element, is combined using emulation, numerical value and experiment
Mode is rebuild gas film pressure distribution by equivalent-circuit model, compares, verified with this equivalent with simulation result and experimental result
The correctness of circuit model.However, vapour lock is practical to be in due to the compressibility of gas and the complexity of flow controller internal structure
It is existing non-linear, while vapour lock is not defined accurately in traditional theory, when causing to be calculated using equivalent-circuit model
There are large errors.Vapour lock is defined as the parameter determined by pipeline size herein, while by gas density and along journey
The influence of resistance coefficient, definition are R=λ ρ l/A, and wherein R is vapour lock value, and λ is frictional resistant coefficient, and ρ is gas density, l
For length of pipe, A is pipe section product.
Due to being mostly the other cylindrical flow of grade inside flow controller, it is therefore necessary to develop a kind of high-precision capillary tube
Road vapour lock measuring device and measuring method, research vapour lock R and gas density ρ, frictional resistant coefficient λ, length of pipe l and pipeline are cut
Relationship between area A, the foundation for gas-static flow controller equivalent-circuit model provide important foundation.
Summary of the invention
In view of the deficiencies of the prior art, the present invention provides a kind of capillary pipeline vapour lock measuring device and measuring method, solutions
The problem that knitting wool pipeline vapour lock of having determined measurement is difficult and precision is not high.
The technical solution adopted by the present invention to solve the technical problems is:
Measuring device in the present invention includes two-stage tandem loop pressure-stabilizing gas source, measurement module, hardware system and calculating
Machine.
The two-stage tandem loop pressure-stabilizing gas source is connect with measurement module by tracheae；The measurement module is for adopting
Collect temperature, pressure and the flow by capillary pipeline of tested capillary pipeline input terminal and output end；The hardware controls
System is used for closed-loop control, the adjusting of loine pressure and the transmission of sensing data of two-stage tandem loop pressure-stabilizing gas source；Institute
The computer stated is for gas computing the resistor value and vapour lock specificity analysis.
The measurement module includes air filtration valve, oil mist separator, electric Proportion valve, the initial segment capillary pipeline, enters
Mouth temperature sensor, inlet connecting, inlet pressure transducer, tested capillary pipeline one, the electrodeless clip of monaural, tested capillary
Road two, outlet connector, outlet pressure sensor, outlet temperature sensor, outflow section capillary pipeline, gas mass flow meter,
Current signal generator, aluminum profile bracket, divergent nozzle.Air filtration valve, oil mist separator and the electric Proportion valve can
It is directly cooperatively connected, the output end of the electric Proportion valve is connected with the initial segment capillary pipeline, the initial segment capillary
The output end on road is connected with the input terminal of the inlet connecting, the output end of inlet connecting and the tested capillary
The input terminal on road one is connected, and the inlet temperature sensor and the inlet pressure transducer are connected through a screw thread mode and pacify
At the blind hole of inlet connecting side, the input of the output end of the tested capillary pipeline two and the outlet connector
End is connected, and tested capillary pipeline one and tested capillary pipeline two are attached by the electrodeless clip of monaural, are fixed, described
Outlet temperature sensor and the outlet pressure sensor be connected through a screw thread mode to be installed on outlet connector side blind
At hole, the output end of outlet connector is connected with the input terminal of the outflow section capillary pipeline, flows out the defeated of section capillary pipeline
Outlet is connected with the input terminal of the gas mass flow meter, the output end connection of the gas mass flow meter flaring spray
Mouth.
The diameter of bore and the initial segment capillary pipeline of the inlet connecting and outlet connector, tested capillary pipeline
One, it is consistent with outflow section capillary pipeline internal diameter to be tested capillary pipeline two, pacifies by way of the open-blind hole of inlet connecting side
Loading port temperature sensor and inlet pressure transducer, the installation outlet equally by way of in outlet connector side open-blind hole
Temperature sensor and outlet pressure sensor, the influence for flowing installation sensor and connecting line to gas in pipeline are down to most
It is small.
The measurement module integral installation on the aluminum profile bracket, while aluminum profile bracket be mounted on it is described
On optical platform, reduce the vibration that device is subject to.
Capillary pipeline vapour lock is measured using above-mentioned apparatus, which comprises the following steps:
Step 1: air accumulator being inflated, 1.0Mpa is inflated to, control gas source output accuracy is maintained within 2%；
Step 2: changing the opening and closing degree of electric Proportion valve by current signal generator, then change the input gas of measurement module
Pressure；
Step 3: the air pressure and temperature of tested pipeline input terminal are measured by inlet pressure transducer and inlet temperature sensor, by going out
Mouth pressure sensor and outlet temperature sensor measure the air pressure and temperature of tested pipeline output end, are measured by gas mass flow
The flow that amount passes through pipeline；
Step 4: by hardware system by entrance and exit pressure sensor, inlet and outlet temperatures sensor and gaseous mass
The data of flowmeter are transmitted to computer, calculate vapour lock value according to formula R=λ ρ l/A by program；
Step 5: changing the input air pressure of measurement module by electric Proportion valve, repeat step 2 to step 4, until measurement module
Input air pressure reach maximum, data are saved by program and draw the characteristic curve of vapour lock under different input air pressures, while can be divided
Gassing hinders characteristic.
Compared with the background art, the beneficial effects of the present invention are:
1, by measuring the vapour lock value of capillary pipeline, drawing vapour lock characteristic curve and analyzing vapour lock characteristic, it is further applicable to gas
In body static pressure flow controller, the foundation for gas-static flow controller equivalent-circuit model provides important foundation, throttles to gas-static
The design and Performance Evaluation of device provide the parameters such as more easy method, including bearing capacity, rigidity and stability.
2, the micro temperature sensor and micro pressure sensor used, probe diameter are less than 2mm, pass through independent design
Connector realizes the measurement of tested capillary pipeline pressure at two ends and temperature, while realizing sensor installation and connecting line,
Influence to inner air path minimizes, and ensure that the precision of measurement result.
3, compared with traditional theoretical calculation, numerical simulation, measuring speed faster, and precision with higher.
Detailed description of the invention
Fig. 1 is capillary pipeline vapour lock measuring device structural schematic diagram of the present invention.
Fig. 2 is the measurement module structure chart in the present invention.
Fig. 3 is hardware system schematic diagram of the invention.
Fig. 4 is the work flow diagram that the present invention completes one-shot measurement.
Specific embodiment
Below in conjunction with attached drawing, the invention will be further described.
As shown in Figure 1, apparatus of the present invention are divided into four modules, including two-stage tandem loop pressure-stabilizing gas source 1, measurement module 2,
Hardware system 4 and computer 3.Measurement module 2 and computer 3 are placed on optical platform 5, two-stage tandem loop pressure-stabilizing gas
Source 1 is connect by tracheae with measurement pipeline 2.
As shown in Fig. 2, measurement pipeline includes air filtration valve 6, oil mist separator 7, electric Proportion valve 8, the initial segment capillary
Pipeline 9, inlet temperature sensor 10, inlet connecting 11, inlet pressure transducer 12, tested capillary pipeline 13, monaural are electrodeless
Clip 14, tested capillary pipeline 15, outlet connector 16, outlet pressure sensor 17, outlet temperature sensor 18, outflow section hair
Tubule road 19, gas mass flow meter 20, current signal generator 21, aluminum profile bracket 22, divergent nozzle 23.The air
Strainer valve 6, oil mist separator 7 and electric Proportion valve 8 can directly be cooperatively connected, the output end of the electric Proportion valve 8 and institute
The initial segment capillary pipeline 9 stated is connected, the input terminal phase of the output end of the initial segment capillary pipeline 9 and the inlet connecting 11
Even, the output end of inlet connecting 11 is connected with the input terminal of the tested capillary pipeline 13, the inlet temperature sensing
Device 10 and the inlet pressure transducer 12 are connected through a screw thread mode and are installed at 11 side blind hole of inlet connecting, described
The output end of tested capillary pipeline 15 be connected with the input terminal of the outlet connector 16, be tested capillary pipeline 13 and tested
Capillary pipeline 15 is attached, is fixed by the electrodeless clip 14 of monaural, the outlet temperature sensor 18 with it is described
Outlet pressure sensor 17 be connected through a screw thread mode and be installed at 16 side blind hole of outlet connector, outlet connector 16
Output end is connected with the input terminal of the outflow section capillary pipeline 19, flows out the output end and the gas of section capillary pipeline 19
The input terminal of weight flowmeter 20 is connected, the output end connection of gas mass flow meter 20 divergent nozzle 23.
As shown in figure 3, the electric-control system in the present invention include sensor module, signal conversion circuit, analog to digital conversion circuit,
STM32 system board, voltage conversion circuit, pneumatic control circuits, serial communication circuit, computer.
It is illustrated in figure 4 the work flow diagram that one-shot measurement is completed using apparatus of the present invention, detailed process is as follows:
Start to measure, system initialization is inflated air accumulator, measures whether air pressure in gas tank reaches 1.0Mpa, if not reaching
It arrives, then continues to inflate into gas tank；If having reached, stop inflating；Electric Proportion valve 8 is changed by current signal generator 21
Opening and closing degree then changes the input air pressure of measurement module 3；It is measured by inlet pressure transducer 12 and inlet temperature sensor 10
It is defeated to measure tested pipeline by outlet pressure sensor 17 and outlet temperature sensor 18 for the air pressure and temperature of tested pipeline input terminal
The air pressure and temperature of outlet, the flow that pipeline is passed through by the measurement of gas mass flow meter 20；Pressure is passed by hardware system 3
The data of sensor 12 and 17, temperature sensor 10 and 18 and gaseous mass flowmeter 20 are transmitted to computer 4, by program according to public affairs
Formula R=λ ρ l/A calculates vapour lock value；If the input air pressure of measurement module 3 is not up to maximum, continue to increase by electric Proportion valve 8
The input air pressure of big measurement module 3, duplicate measurements simultaneously calculate vapour lock value；If the input air pressure of measurement module 3 has reached maximum,
Stop measurement, data are saved by program and draw the characteristic curve of vapour lock under different input air pressures, while vapour lock characteristic can be analyzed.
Claims (3)
1. a kind of capillary pipeline vapour lock measuring device, it is characterised in that: the device includes two-stage tandem loop pressure-stabilizing gas source (1),
For providing high accuracy and stability air pressure output；Measurement module (2), for measure the temperature in capillary pipeline, air pressure with
And the flow for passing through capillary pipeline；Hardware system (3), closed-loop control, pipeline for two-stage tandem loop pressure-stabilizing gas source
The adjusting of air pressure and the transmission of sensing data；Computer (4), for gas computing the resistor value and vapour lock specificity analysis；
The measurement module (2) includes air filtration valve (6), oil mist separator (7), electric Proportion valve (8), the initial segment capillary
Pipeline (9), inlet temperature sensor (10), inlet connecting (11), inlet pressure transducer (12), tested capillary pipeline
(13), the electrodeless clip of monaural (14), tested capillary pipeline (15), outlet connector (16), outlet pressure sensor (17), outlet
Temperature sensor (18), outflow section capillary pipeline (19), gas mass flow meter (20), current signal generator (21), aluminium profiles
Material bracket (22), divergent nozzle (23)；Air filtration valve (6), oil mist separator (7) and the electric Proportion valve (8) can be straight
Mating connection is connect, the output end of the electric Proportion valve (8) is connected with the initial segment capillary pipeline (9), the initial segment hair
The output end on tubule road (9) is connected with the input terminal of the inlet connecting (11), the output end of inlet connecting (11) with
The input terminal of the tested capillary pipeline (13) is connected, and the inlet temperature sensor (10) and the inlet pressure pass
Sensor (12) mode of being connected through a screw thread is installed at the blind hole of inlet connecting (11) side, the tested capillary pipeline (15)
Output end be connected with the input terminal of the outlet connector (16), be tested capillary pipeline (13) and tested capillary pipeline (15)
It is attached, fixed by the electrodeless clip of monaural (14), the outlet temperature sensor (18) and the outlet
Pressure sensor (17) mode of being connected through a screw thread is installed at the blind hole of outlet connector (16) side, outlet connector (16)
Output end is connected with the input terminal of the outflow section capillary pipeline (19), flow out section capillary pipeline (19) output end with it is described
The input terminal of gas mass flow meter (20) be connected, the output end of gas mass flow meter (20) the connection divergent nozzle
(23)。
2. measurement module according to claim 1, it is characterised in that: inlet connecting (11) and outlet connector (16)
Diameter of bore and the initial segment capillary pipeline (9), tested capillary pipeline (13), tested capillary pipeline (15) and outflow section capillary pipeline
(19) internal diameter is consistent, installing inlet temperature sensor (10) and entrance by way of inlet connecting (11) side open-blind hole
Pressure sensor (12), the installation outlet temperature sensor (18) equally by way of in outlet connector (16) side open-blind hole
With outlet pressure sensor (17), the influence for flowing installation sensor and connecting line to gas in pipeline is minimized.
3. a kind of capillary pipeline vapour lock measurement method, which is characterized in that mainly comprise the steps that
Step 1: air accumulator being inflated, 1.0Mpa is inflated to, control gas source output accuracy is maintained within 2%；
Step 2: changing the opening and closing degree of electric Proportion valve (8) by current signal generator (21), then change measurement module (3)
Input air pressure；
Step 3: by inlet pressure transducer (12) and inlet temperature sensor (10) measure tested pipeline input terminal air pressure and
Temperature is measured the air pressure and temperature of tested pipeline output end by outlet pressure sensor (17) and outlet temperature sensor (18),
The flow that pipeline is passed through by gas mass flow meter (20) measurement；
Step 4: by hardware system (3) by the data of pressure sensor (12) and (17), temperature sensor (10) and (18)
Computer (4) are transmitted to, vapour lock value is calculated by program；
Step 5: changing the input air pressure of measurement module (3) by electric Proportion valve (8), repeat step 2 to step 4, until defeated
Enter air pressure and reach maximum, data are saved by program and draw the characteristic curve of vapour lock under different input air pressures, while gas can be analyzed
Hinder characteristic.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201910830824.4A CN110470569A (en) | 2019-09-04 | 2019-09-04 | A kind of capillary pipeline vapour lock measuring device and measuring method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201910830824.4A CN110470569A (en) | 2019-09-04 | 2019-09-04 | A kind of capillary pipeline vapour lock measuring device and measuring method |
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| CN201910830824.4A Pending CN110470569A (en) | 2019-09-04 | 2019-09-04 | A kind of capillary pipeline vapour lock measuring device and measuring method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112539929A (en) * | 2020-12-01 | 2021-03-23 | 中国计量大学 | Inlet and outlet parameter measuring device of gas static pressure restrictor |
| CN113324579A (en) * | 2021-02-05 | 2021-08-31 | 南京工业大学 | Detection system and detection method for liquid resistance of capillary restrictor |
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| TW200821788A (en) * | 2006-11-10 | 2008-05-16 | Univ Chung Yuan Christian | Measurement instrument for restriction parameter and flow resistance |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112539929A (en) * | 2020-12-01 | 2021-03-23 | 中国计量大学 | Inlet and outlet parameter measuring device of gas static pressure restrictor |
| CN113324579A (en) * | 2021-02-05 | 2021-08-31 | 南京工业大学 | Detection system and detection method for liquid resistance of capillary restrictor |
| CN113324579B (en) * | 2021-02-05 | 2022-03-08 | 南京工业大学 | Detection system and detection method for liquid resistance of capillary restrictor |
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Application publication date: 20191119 |