CN107515030A - A kind of each sound channel flow velocity weight coefficient of multichannel ultrasonic flowmeter determines method - Google Patents
A kind of each sound channel flow velocity weight coefficient of multichannel ultrasonic flowmeter determines method Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/66—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
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Abstract
The invention discloses a kind of each sound channel flow velocity weight coefficient of multichannel ultrasonic flowmeter to determine method, including：Establish the projection model of the wherein single sound channel of multichannel ultrasonic flowmeter；Based on single sound channel projection model, sound channel overlay area Velocity Formula is derived；According to Reynolds number size, tube wall degree of roughness, each sound channel flow velocity weight coefficient of calculating multichannel ultrasonic flowmeter.The suitable different type of the present invention, different size, different shape size multichannel ultrasonic flowmeter, each sound channel flow velocity weight coefficient for solving multichannel ultrasonic flowmeter determines problem, contribute to the cost of reduction multichannel flowmeter, promote multichannel ultrasonic flowmeter application.
Description
Technical field
The present invention relates to flowmeter performance lift technique field, more particularly to a kind of each sound channel of multichannel ultrasonic flowmeter
Flow velocity weight coefficient determines method.
Background technology
Metering is industrial eyes.Flow measurement is one of part of measuring science technology, and it is passed through with national
Ji, national defense construction, scientific research have close relationship.This work is carried out, to ensureing product quality, improving production efficiency, rush
Enter science and technology development all have the function that it is important, it is particularly more and more high in energy crisis, industrial production automation degree
Current era, status of the flowmeter in national economy and effect it is more obvious.
As pipe diameter increases, measurement range becomes wide, the information of flow that single sound channel can obtain is relatively limited, passes through
Increase number of channels is to improve flow measurement accuracy important method, wherein staggered form to lift sound channel stream field level of coverage
Multichannel number can be more, and change is flexible, larger sound channel design space be present, complexity is high, can offset radial flow speed and cause
Error, better performances, in being, the important equipment of large diameter pipe flow measurement.But the sound channel weight coefficient of existing multichannel also lacks
Weary more unified determination method, process are complicated.
The content of the invention
In order to solve the above technical problems, it is an object of the invention to provide a kind of each sound channel flow velocity of multichannel ultrasonic flowmeter
Weight coefficient determines method, and each sound channel flow velocity weight coefficient that this method solve multichannel ultrasonic flowmeter determines problem, has
Help reduce the application cost of multichannel flowmeter.
The purpose of the present invention is realized by following technical scheme：
A kind of each sound channel flow velocity weight coefficient of multichannel ultrasonic flowmeter determines method, including：
A establishes the projection model of the wherein single sound channel of multichannel ultrasonic flowmeter；
B is based on single sound channel projection model, derives sound channel overlay area Velocity Formula；
According to Reynolds number size, tube wall degree of roughness, each sound channel flow velocity weighting for calculating multichannel ultrasonic flowmeter is C
Number.
Compared with prior art, one or more embodiments of the invention can have the following advantages that：
The suitable different type of the present invention, different size, different shape size multichannel ultrasonic flowmeter, solve multichannel
Each sound channel flow velocity weight coefficient of ultrasonic flowmeter determines problem, helps to reduce the cost of multichannel flowmeter, promotes more sound
Road ultrasonic flowmeter application.
Brief description of the drawings
Fig. 1 is that each sound channel flow velocity weight coefficient of multichannel ultrasonic flowmeter determines method flow；
Fig. 2 is the projection model figure of the wherein single sound channel of multichannel ultrasonic flowmeter.
Embodiment
To make the object, technical solutions and advantages of the present invention clearer, below in conjunction with embodiment and accompanying drawing to this hair
It is bright to be described in further detail.
As shown in figure 1, method flow is determined for each sound channel flow velocity weight coefficient of multichannel ultrasonic flowmeter, including：
Step 10 establishes the projection model of the wherein single sound channel of multichannel ultrasonic flowmeter；
Step 20 is based on single sound channel projection model, derives sound channel overlay area Velocity Formula；
According to Reynolds number size, tube wall degree of roughness, each sound channel flow velocity for calculating multichannel ultrasonic flowmeter adds step 30
Weight coefficient.
The projection model of the wherein single sound channel of above-mentioned multichannel ultrasonic flowmeter, be using any sound channel as example, rather than
Particular channel.
Single sound channel i in the step 10 in multichannel is by Np_iDuan Shengdao sections are formed, wherein sound channel section Pi,jPi,j+1With
Origin O distances are di,j, 1≤j≤Np_i；To wherein one section of sound channel section Pi,jPi,j+1P ' is projected as in cross-section of pipelinei,jP′i,j+1,
P′i,jP′i,j+1Length is li,j, corresponding central angle is 2 αi,j, internal diameter of the pipeline Dp, sound channel width is Dsig。
Flow velocity is v (r), P ' on r distribution function on cross section in above-mentioned steps 20i,jP′i,j+1Regional fluid is averaged
Flow velocity isThen by P 'i,jP′i,j+1FlowInfinitesimal δ l at r are pointed to, if infinitesimal region flow velocity is
δ v, then pass through infinitesimal flow δ Q ≈ δ v δ lDsig；AgainBoth sides
Integrate simultaneously：
AgainTherefore
To by Np_iThe single sound channel i that Duan Shengdao sections are formed, its overlay area Velocity Formula are
In formula, Np_iThe sound channel hop count included for single sound channel i, v (r) are distribution letter of the flow velocity on cross section on r
Number, αi,jFor Np_iDuan Shengdao projection Ps 'i,jP′i,j+1The half of corresponding central angle, di,jFor sound channel section projection P 'i,jP′i,j+1
With origin O distances, li,jFor sound channel section projection P 'i,jP′i,j+1Length.
When reynolds number Re≤2300, the single sound channel i of multichannel flow velocity weight coefficient is：
As reynolds number Re ＞ 2300, hlf=34.2Dp/Re0.875＜ 0.0391Dp, and hlfExponentially subtract with Re increases
It is small, thus whole cross section can be calculated ω with transition zone, turbulent-flow core heart districti；
If inner-walls of duct is smooth, the single sound channel i of multichannel flow velocity weight coefficient is：
If inner-walls of duct is coarse, the single sound channel i of multichannel flow velocity weight coefficient is：
In formula, DpFor internal diameter of the pipeline, Np_iFor sound channel i sound channel hop count, di,jFor sound channel section Pi,jPi,j+1With origin O away from
From,Pipeline section mean flow rate, e are natural constant, μfluidFor fluid kinematic viscosity coefficient, ρfluidFor fluid density, f=
0.79·Re-0.25For Fanning friction factor, kδFor the pipeline equivalent coefficient of roughness.
Although disclosed herein embodiment as above, described content only to facilitate understand the present invention and adopt
Embodiment, it is not limited to the present invention.Any those skilled in the art to which this invention pertains, this is not being departed from
On the premise of the disclosed spirit and scope of invention, any modification and change can be made in the implementing form and in details,
But the scope of patent protection of the present invention, still should be subject to the scope of the claims as defined in the appended claims.
Claims (4)
1. a kind of each sound channel flow velocity weight coefficient of multichannel ultrasonic flowmeter determines method, it is characterised in that methods described bag
Include：
A establishes the projection model of the wherein single sound channel of multichannel ultrasonic flowmeter；
B is based on single sound channel projection model, derives sound channel overlay area Velocity Formula；
C is according to Reynolds number size, tube wall degree of roughness, each sound channel flow velocity weight coefficient of calculating multichannel ultrasonic flowmeter.
2. each sound channel flow velocity weight coefficient of multichannel ultrasonic flowmeter as claimed in claim 1 determines method, its feature exists
In the single sound channel i in the step A in multichannel is by Np_iDuan Shengdao sections are formed, wherein sound channel section Pi,jPi,j+1With origin O away from
From for di,j, 1≤j≤Np_i；To wherein one section of sound channel section Pi,jPi,j+1P ' is projected as in cross-section of pipelinei,jP′i,j+1, P 'i, jP′i,j+1Length is li,j, corresponding central angle is 2 αi,j, internal diameter of the pipeline Dp, sound channel width is Dsig。
3. each sound channel flow velocity weight coefficient of multichannel ultrasonic flowmeter as claimed in claim 1 determines method, it is characterised in that institute
It is v (r), P ' on r distribution function on cross section to state flow velocity in step Bi,jP′i,j+1Regional fluid mean flow rate isThen pass through
P′i,jP′i,j+1FlowInfinitesimal δ l at r are pointed to, if infinitesimal region flow velocity is δ v, pass through infinitesimal flow δ Q
≈δv·δl·Dsig；Again
Both sides integrate simultaneously：
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4. each sound channel flow velocity weight coefficient of the multichannel ultrasonic flowmeter as described in claim 1 or 3 determines method, its feature
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If inner-walls of duct is coarse, the single sound channel i of multichannel flow velocity weight coefficient is
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In formula, DpFor internal diameter of the pipeline, Np_iFor sound channel i sound channel hop count, di,jFor sound channel section Pi,jPi,j+1With origin O distance,
Pipeline section mean flow rate, e are natural constant, μfluidFor fluid kinematic viscosity coefficient, ρfluidFor fluid density, f=0.79
Re-0.25For Fanning friction factor, kδFor the pipeline equivalent coefficient of roughness.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103074873A (en) * | 2013-02-07 | 2013-05-01 | 天津大学 | Channel arrangement method of multichannel ultrasonic flow meter in nonideal flow field |
| JP2015078962A (en) * | 2013-10-18 | 2015-04-23 | 独立行政法人 宇宙航空研究開発機構 | Flow measuring method and flow measuring apparatus |
| CN106017582A (en) * | 2016-05-06 | 2016-10-12 | 中南大学 | A pitot tube flow measuring method based on the tube diameter dichotomy principle |
| CN106895890A (en) * | 2017-04-25 | 2017-06-27 | 浙江大学 | A kind of multichannel ultrasonic gas flowmeter sound channel weight coefficient computational methods |
-
2017
- 2017-08-30 CN CN201710760430.7A patent/CN107515030B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103074873A (en) * | 2013-02-07 | 2013-05-01 | 天津大学 | Channel arrangement method of multichannel ultrasonic flow meter in nonideal flow field |
| JP2015078962A (en) * | 2013-10-18 | 2015-04-23 | 独立行政法人 宇宙航空研究開発機構 | Flow measuring method and flow measuring apparatus |
| CN106017582A (en) * | 2016-05-06 | 2016-10-12 | 中南大学 | A pitot tube flow measuring method based on the tube diameter dichotomy principle |
| CN106895890A (en) * | 2017-04-25 | 2017-06-27 | 浙江大学 | A kind of multichannel ultrasonic gas flowmeter sound channel weight coefficient computational methods |
Non-Patent Citations (4)
| Title |
|---|
| LIU Y, DU G, LIU Z等: "The profile-linear average velocity for the transition in pipes based on the method of LES", 《JOURNAL OF HYDRODYNAMICS》 * |
| 刘永辉: "圆管过渡区流速特性的研究", 《中国博士学位论文全文数据库工程科技2辑》 * |
| 周迈: "《高等数学上》", 30 September 2016, 南开大学出版社 * |
| 李良，周雄: "《工程流体力学》", 31 August 2016, 冶金工业出版社 * |
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