CN109443499A - A kind of electronics temperature compensation diaphragm gas meter error of indication dynamic testing method - Google Patents
A kind of electronics temperature compensation diaphragm gas meter error of indication dynamic testing method Download PDFInfo
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- CN109443499A CN109443499A CN201811042665.3A CN201811042665A CN109443499A CN 109443499 A CN109443499 A CN 109443499A CN 201811042665 A CN201811042665 A CN 201811042665A CN 109443499 A CN109443499 A CN 109443499A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F25/00—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume
- G01F25/10—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume of flowmeters
- G01F25/15—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume of flowmeters specially adapted for gas meters
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Abstract
The invention discloses a kind of electronics temperature compensation diaphragm gas meter error of indication dynamic testing method, include the following steps: that S1, gas flow standard device setting test flow, detection umber of pulse N, stablize starting test after the time at impulse ratio f；S2, after the 1st pulse of sampler automatic collection to mechanical counter, standard timing starts, after collecting N+1 umber of pulse of mechanical counter, standard timer expiration；S3 calculates normal temperature volumetric pulse coefficient；The display on electronic counter while gas flow standard device samples mechanical counter and tests, when manually reading a-th of pulse of electronic counter and (a+M) a pulse；Finally calculate the error of indication of electronic counter normal temperature lower volume.The present invention is on the basis of automatic sampling is arranged in existing gas flow standard device, in conjunction with artificial reading, completes to show electronic counter form the error of indication of normal temperature volume is tested, the accuracy of measuring is high, and the testing time is short.
Description
Technical field
The present invention relates to gauge check technologies, and in particular to the method for gas meter, flow meter of the detection with temperature compensation function.
Background technique
Currently, the detection method of the gas meter, flow meter with temperature compensation function includes that dynamic method calibrating and static method test two kinds of sides
Method.Consider from gas meter, flow meter measuring angle, dynamic method calibrating is examined and determine under combustion gas table simulation working condition, can be preferably
Reflect the gas meter, flow meter metering performance.Static method necessarily introduces human error, and static method since there are manual operation factors
There are shutdown processes can have an impact to metric results due to effect of inertia for metering gas table.
Dynamic method examines and determine the working condition for going out gas meter, flow meter by single-chip simulation, and single-chip microcontroller receives operating condition pulse and temperature,
The volume of outputting standard temperature is shown in the form of electronic counter.When detection device test error, only with checklist synchronometer
Amount volume just can ensure that accuracy.Dynamic method carrys out the metering of trigger criteria volume with the signal of checklist when testing, at present can only
Mechanical counter and the signal of LED are collected, and it is invalid to electronic digit, so can not dynamically test.
It takes static method to test, first reads the initial reading of checklist, after ventilation, then read the termination reading of checklist,
Thus the volume by checklist is calculated, then is compared with according to the volume for flowing through standard.Between being due to electronic counting
Having a rest property, pulse signal ability counting is only received, the two the asynchronous of volume metering is caused to cause error.A in Fig. 1
Point, standard volume is 33 liters, and checklist electronic counter volume reading or 22 liters, 11 liters is differed, if 100 liters of test
Gas, error reach 11%, cause very big measurement error, only increase test volume to 5000 to improve test accuracy
Rise, it is asynchronous caused by deviation brought by 11 liters be 0.2%, just can be ignored, thus need to purchase new equipment, greatly
Temperature has variation, influences test accuracy in extended testing system time, test process.
Summary of the invention
The technical problem to be solved by the invention is to provide a kind of electronics temperature compensation diaphragm gas meter error of indication dynamics to survey
Method for testing realizes that dynamic method quickly, accurately examines and determine the error of indication of electronic counter.
In order to solve the above technical problems, the present invention adopts the following technical scheme: a kind of electronics temperature compensation diaphragm gas meter indicating value
Error dynamics test method, includes the following steps:
S1, gas flow standard device setting test flow impulse ratio f, detect umber of pulse N, start after the stable time
Test；
S2, after the 1st pulse of sampler automatic collection to mechanical counter, standard timing starts, when collecting machine
After the N+1 umber of pulse of tool counter, standard timer expiration；
S3 calculates normal temperature volumetric pulse coefficient；
It is artificial to read a-th of electronic counter while gas flow standard device samples mechanical counter and tests
The display on electronic counter when pulse and (a+M) a pulse；
The error of indication of electronic counter normal temperature lower volume is finally calculated,
In formula:
Cumulative volume (m at a temperature of-M pulsed electron counter criterion3)；- a-th pulsed electron counter
Normal temperature lower volume reads (m3)；Volume reading (m at a temperature of a pulsed electron counter criterion of-the (a+M)3)；
Cumulative volume (m under-M actual normal temperature of pulse3)；fB- normal temperature volumetric pulse coefficient (m3/P)；EBStandard temperature
Spend the error of indication (%) of lower lower volume.
Preferably, the gas flow standard device is Sonic Nozzle Gas Flow Standard Device.
Preferably, the calculation method of the normal temperature volumetric pulse coefficient is
Vm=f × N (1)
fB=f/ (1+E) (5)
In formula:
VmThe operating condition volume (m3) of checklist；Operating condition volume (the m of Vs- nozzle3)；A-area of nozzle throat (m2)；C
′d- it is efflux coefficient；C*- it is critical flow；Z0- it is compressibility factor；TS- be nozzle entrance aerothermodynami temperature
(K)；M-gas molar quality (kg.mol-1)；R- universal gas constant (J.mol-1.K-1)；T-time of measuring (s)；Ps—
Gas absolute pressure (Pa) in standard；Gas absolute pressure (Pa) at Pm-checklist；TB- reference gas temperature
293.15K；Vref- pass through the bulking value (m under checklist normal temperature3)；E-the error of indication (%)；F-operating condition impulse ratio
(m3/P)；fB- normal temperature volumetric pulse coefficient (m3/P)。
Preferably, umber of pulse N >=10 are detected.
Preferably, umber of pulse M >=6.
The technical solution adopted by the present invention, on the basis of automatic sampling is arranged in existing gas flow standard device, in conjunction with people
Part work and part study number is completed to show electronic counter form the error of indication of normal temperature volume is tested.
Therefore, the invention has the following beneficial effects:
1, it is tested using dynamic method, the working condition of gas meter, flow meter is gone out by single-chip simulation, shown in the form of electronic counter
The volume of outputting standard temperature, compared with static method test, the accuracy of measuring is high, and the testing time is short, and test shortened for 98% time；
2, existing detection device is not changed, it is only necessary to increase the artificial display read on electronic counter and corresponding meter
Step is calculated, the error of indication of electronic counter normal temperature lower volume can be calculated, without increasing extra cost；
3, versatile, it is suitble to gas flow standard devices all at present, such as sonic nozzle gas flow standard dress
It sets, bell-jar gas flow standard equipment, velocity-area method gas flow standard device, high pressure piston gas flow standard dress
It sets.
4, using Sonic Nozzle Gas Flow Standard Device, with use other flowmeters as standard scale compared with, sprayed with velocity of sound
Mouth as standard scale have lot of advantages, as structure is simple, performance is stable, accuracy is high, without movable member, it is easy to maintain, inspection
Fixed cycle length etc..
5, umber of pulse N >=10 are preferably detected, umber of pulse M >=6 will affect measuring accuracy if detection umber of pulse N is too small,
Same umber of pulse M is too small, will affect the computational accuracy of the error of indication.
The specific technical solution of the present invention and its advantages will in the following detailed description in conjunction with attached drawing into
Row detailed description.
Detailed description of the invention
Present invention will be further described below with reference to the accompanying drawings and specific embodiments:
Fig. 1 is normal volume and electronic counting volume relationship figure；
Fig. 2 is magnitude tracing figure；
Fig. 3 is operating condition pulse volume correction map；
Fig. 4 is the volume relationship figure of operating condition pulse and electronic counting；
Fig. 5 is test sequence figure.
Specific embodiment
Referring to figs. 2 to shown in Fig. 4, wherein gas flow standard device: mechanical for detecting the measurement error of gas meter, flow meter
Volume: the volume of mechanical counter measurement is counted, operating condition pulse volume: the operating condition pulse volume of single-chip microcontroller input, mechanical count
One 10 liters of circle meter of device tail wheel rotation.Operating condition pulse shape modification volume: according to normal volume, operating condition pulse volume is modified.Electricity
Sub-count volume: single-chip microcontroller converts out the volume of normal temperature according to input operating condition pulse volume and temperature with electronic digit side
Formula is shown on a display screen.When temperature is -10 DEG C, operating condition pulse volume is 10 liters, and being converted into electronic counting volume is 11.23
It rises, keeps synchronism between the two, operating condition pulse is N number of, volume conversion n times.
The magnitude tracing figure with reference to shown in Fig. 2, the present invention propose that one kind based on transmission of quantity value test method, is completed to electrometer
Number device form shows the error of indication test of normal temperature volume.Illustrate specific implementation process below in conjunction with Fig. 3 and Fig. 4.
Fig. 3 Plays volume: gas flow standard device detects the volume flowed through under checklist normal temperature.Due to machine
Tool counter can be sampled reading automatically by gas flow standard device, and by test error, operating condition pulse volume is modified to
Pulse volume under normal temperature.
Operating condition pulse volume is modified to exact value by Fig. 4, calculates the error of indication after temperature compensation with this.
Domestic gas meter maximum stream flow is 10m3/ h, it is 3.6s that electronic counting, which updates 1 time, and artificial reading electronic digit, which has, to be filled
Between timesharing.A kind of electronics temperature compensation diaphragm gas meter error of indication dynamic testing method of the present invention is filled in existing gas flow standard
On the basis of installing automatic sampling, in conjunction with artificial reading, the indicating value that normal temperature volume is shown to electronic counter form is completed
Error testing.The present invention includes the following steps:
S1, gas flow standard device setting test flow impulse ratio f, detect umber of pulse N, start after the stable time
Test；
S2, after the 1st pulse of sampler automatic collection to mechanical counter, standard timing starts, when collecting machine
After the N+1 umber of pulse of tool counter, standard timer expiration；
S3 calculates normal temperature volumetric pulse coefficient；
It is artificial to read a-th of electronic counter while gas flow standard device samples mechanical counter and tests
The display on electronic counter when pulse and (a+M) a pulse；Finally calculate electronic counter normal temperature lower body
The long-pending error of indication, calculation method are to correct M pulsed electron counter criterion according to normal temperature volumetric pulse coefficient first
At a temperature of cumulative volume, obtain cumulative volume under the actual normal temperature of M pulse, then compare M pulsed electron counter
Cumulative volume and cumulative volume under the actual normal temperature of M pulse, calculate electronic counter normal temperature under normal temperature
The error of indication of lower volume.
Above-mentioned N and M is umber of pulse, therefore can only be integer, theoretically for, detection umber of pulse N and umber of pulse M be
More, precision is higher, but excessively will affect testing efficiency, it is therefore preferable that detection umber of pulse N >=10, umber of pulse M >=6, if
It is too small to detect umber of pulse N, will affect measuring accuracy, same umber of pulse M is too small, will affect the computational accuracy of the error of indication.
Below for using sonic nozzle method gas flow standard device, illustrate electronics temperature compensation diaphragm gas meter of the present invention
Error of indication dynamic testing method.
When the ratio between outlet pressure of sonic nozzle is certain value to gas after film table enters container, the Reynolds of nozzle throat
Number is certain, then air-flow passes through the constant flow rate of nozzle candidate, at this time as critical stream mode.According to the principle of continuity, lead at this time
The gas mass flow of checklist is crossed, certain mass flow being equal to through gas at nozzle.Refering to what is shown in Fig. 5, sonic nozzle
Method gas flow standard device setting test flow, impulse ratio f, detection umber of pulse N, stablize the time after start test, when adopting
After sample device automatic collection to the 1st pulse of mechanical counter, standard timing starts, a when collecting mechanical counter N+1
After umber of pulse, standard timer expiration.
Formula (1) calculates the operating condition volume of checklist, and formula (2) calculates at this time through critical flow venturi nozzle
The operating condition volume of nozzle is converted into the volume of the pressure and normal temperature at checklist, formula (4) by operating condition volume, formula (3)
The error of indication under the normal temperature that mechanical counter is shown is calculated, impulse ratio f is modified to normal temperature body by formula (5)
Product impulse ratio.
Vm=f × N (1)
fB=f/ (1+E) (5)
In formula:
VmThe operating condition volume (m3) of checklist；Vs-nozzle operating condition volume (m3)；A-area of nozzle throat (m2)；C
′dIt is efflux coefficient；C*It is critical flow；Z0It is compressibility factor；TSIt is the aerothermodynami temperature (K) of nozzle entrance；
M- gas molar quality (kg.mol-1)；R- universal gas constant (J.mol-1.K-1)；T-time of measuring (s)；Ps-standard
Interior gas absolute pressure (Pa)；Gas absolute pressure (Pa) at Pm-checklist；TB- reference gas temperature 293.15K；
Vref- pass through the bulking value (m under checklist normal temperature3)；The E- error of indication (%)；F- operating condition impulse ratio (m3/P)；fB-
Normal temperature impulse ratio (m3/P)。
While sonic nozzle method gas flow standard device samples mechanical counter and tests, electrometer is manually read
Display on number device, reads electronic counter when a-th of pulse and (a+M) pulse.
Formula (6) calculates cumulative volume at a temperature of M pulsed electron counter criterion.Formula (7) calculates M pulse
Cumulative volume under actual normal temperature.Formula (8) calculates the error of indication of electronic counter normal temperature lower volume.
Cumulative volume (m at a temperature of-M pulsed electron counter criterions3)；- a-th pulsed electron counter criterion
At a temperature of volume reading (m3)；Volume reading (m at a temperature of a pulsed electron counter criterion of-the (a+M)3)；- M arteries and veins
Rush cumulative volume (m under actual normal temperature3)；EBThe error of indication (%) of lower volume under-normal temperature.
Certainly, it will be appreciated by persons skilled in the art that gas flow standard device is not limited to sonic nozzle method gas
Body flow standard device, such as bell-jar gas flow standard equipment, velocity-area method gas flow standard device, weighing method gas
Body flow standard device, high pressure piston gas flow standard device etc.；For other gas flow standard devices, standard temperature
Spend volumetric pulse coefficient fBCalculation method be slightly different, but since the calculation method belongs to the prior art, the present invention is herein not
It repeats again.
The above description is merely a specific embodiment, but scope of protection of the present invention is not limited thereto, is familiar with
The those skilled in the art should be understood that the present invention includes but is not limited to content described in specific embodiment above.It is any
Modification without departing from function and structure principle of the invention is intended to be included in the range of claims.
Claims (5)
1. a kind of electronics temperature compensation diaphragm gas meter error of indication dynamic testing method, includes the following steps:
S1, gas flow standard device setting test flow, detection umber of pulse N, stablize starting test after the time at impulse ratio f；
S2, after the 1st pulse of sampler automatic collection to mechanical counter, standard timing starts, when collecting mechanical meter
After number the N+1 umber of pulse of device, standard timer expiration；
S3 calculates normal temperature volumetric pulse coefficient；
It is characterized by: manually reading electronic counting while gas flow standard device samples mechanical counter and tests
The display on electronic counter when a-th of pulse of device and (a+M) a pulse；
The error of indication of electronic counter normal temperature lower volume is finally calculated,
In formula:
Cumulative volume (m at a temperature of-M pulsed electron counter criterions3)；- a-th pulsed electron counter criterion temperature
Lower volume reads (m3)；Volume reading (m at a temperature of a pulsed electron counter criterion of-the (a+M)3)；- M pulses are real
Cumulative volume (m under the normal temperature on border3)；fB- normal temperature volumetric pulse coefficient (m3/P)；EBLower volume under-normal temperature
The error of indication (%).
2. a kind of electronics temperature compensation diaphragm gas meter error of indication dynamic testing method according to claim 1, feature exist
In: the gas flow standard device is Sonic Nozzle Gas Flow Standard Device.
3. a kind of electronics temperature compensation diaphragm gas meter error of indication dynamic testing method according to claim 2, feature exist
In: the calculation method of the normal temperature volumetric pulse coefficient is
Vm=f × N (1)
fB=f/ (1+E) (5)
In formula:
VmThe operating condition volume (m3) of-checklist；Vs-nozzle operating condition volume (m3)；A-area of nozzle throat (m2)；C′d- be
Efflux coefficient；C*- it is critical flow；Z0- it is compressibility factor；TS- be nozzle entrance aerothermodynami temperature (K)；M—
Gas molar quality (kg.mol-1)；R- universal gas constant (J.mol-1.K-1)；T-time of measuring (s)；In Ps-standard
Gas absolute pressure (Pa)；Gas absolute pressure (Pa) at Pm-checklist；TB- reference gas temperature 293.15K；
Vref- pass through the bulking value (m under checklist normal temperature3)；E-the error of indication (%)；F- operating condition impulse ratio (m3/P)；
fB- normal temperature volumetric pulse coefficient (m3/P)。
4. a kind of electronics temperature compensation diaphragm gas meter error of indication dynamic as claimed in any of claims 1 to 3 is tested
Method, it is characterised in that: detection umber of pulse N >=10.
5. a kind of electronics temperature compensation diaphragm gas meter error of indication dynamic testing method according to claim 4, feature exist
In: umber of pulse M >=6.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114235108A (en) * | 2021-12-24 | 2022-03-25 | 华中科技大学无锡研究院 | Method and device for detecting abnormal state of gas flowmeter based on data analysis |
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