CN114812709B - Infrared flowmeter for real-time flow rate measurement of emulsion - Google Patents
Infrared flowmeter for real-time flow rate measurement of emulsion Download PDFInfo
- Publication number
- CN114812709B CN114812709B CN202210483445.4A CN202210483445A CN114812709B CN 114812709 B CN114812709 B CN 114812709B CN 202210483445 A CN202210483445 A CN 202210483445A CN 114812709 B CN114812709 B CN 114812709B
- Authority
- CN
- China
- Prior art keywords
- emulsion
- infrared
- flowmeter
- flow rate
- milk
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000000839 emulsion Substances 0.000 title claims abstract description 89
- 238000005259 measurement Methods 0.000 title claims abstract description 17
- 235000013336 milk Nutrition 0.000 claims abstract description 53
- 239000008267 milk Substances 0.000 claims abstract description 53
- 210000004080 milk Anatomy 0.000 claims abstract description 53
- 238000004422 calculation algorithm Methods 0.000 claims abstract description 10
- 238000009826 distribution Methods 0.000 claims description 23
- 238000004364 calculation method Methods 0.000 claims description 18
- 239000007788 liquid Substances 0.000 claims description 14
- 238000009434 installation Methods 0.000 claims description 4
- 239000002245 particle Substances 0.000 abstract description 9
- 238000000034 method Methods 0.000 abstract description 8
- 235000020251 goat milk Nutrition 0.000 abstract description 6
- 238000004519 manufacturing process Methods 0.000 abstract description 6
- 230000008901 benefit Effects 0.000 abstract description 5
- 235000020248 camel milk Nutrition 0.000 abstract description 5
- 238000001514 detection method Methods 0.000 abstract description 5
- 235000020246 buffalo milk Nutrition 0.000 abstract description 3
- 238000005303 weighing Methods 0.000 abstract description 2
- 241000283690 Bos taurus Species 0.000 description 12
- 239000010410 layer Substances 0.000 description 10
- 239000003925 fat Substances 0.000 description 7
- 102000004169 proteins and genes Human genes 0.000 description 7
- 108090000623 proteins and genes Proteins 0.000 description 7
- 238000009395 breeding Methods 0.000 description 5
- 230000001488 breeding effect Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- 235000013365 dairy product Nutrition 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 230000005484 gravity Effects 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- GUBGYTABKSRVRQ-QKKXKWKRSA-N Lactose Natural products OC[C@H]1O[C@@H](O[C@H]2[C@H](O)[C@@H](O)C(O)O[C@@H]2CO)[C@H](O)[C@@H](O)[C@H]1O GUBGYTABKSRVRQ-QKKXKWKRSA-N 0.000 description 2
- 241001465754 Metazoa Species 0.000 description 2
- 230000009471 action Effects 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 239000008101 lactose Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000011897 real-time detection Methods 0.000 description 2
- 239000002344 surface layer Substances 0.000 description 2
- GUBGYTABKSRVRQ-XLOQQCSPSA-N Alpha-Lactose Chemical compound O[C@@H]1[C@@H](O)[C@@H](O)[C@@H](CO)O[C@H]1O[C@@H]1[C@@H](CO)O[C@H](O)[C@H](O)[C@H]1O GUBGYTABKSRVRQ-XLOQQCSPSA-N 0.000 description 1
- 241000894006 Bacteria Species 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 238000000862 absorption spectrum Methods 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 238000007792 addition Methods 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 235000020247 cow milk Nutrition 0.000 description 1
- 238000009795 derivation Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 229920002521 macromolecule Polymers 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 235000015097 nutrients Nutrition 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 239000011782 vitamin Substances 0.000 description 1
- 235000013343 vitamin Nutrition 0.000 description 1
- 229940088594 vitamin Drugs 0.000 description 1
- 229930003231 vitamin Natural products 0.000 description 1
Classifications
-
- 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
- G01F1/661—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 using light
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
- G06F30/28—Design optimisation, verification or simulation using fluid dynamics, e.g. using Navier-Stokes equations or computational fluid dynamics [CFD]
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Fluid Mechanics (AREA)
- Mathematical Optimization (AREA)
- Computing Systems (AREA)
- Mathematical Analysis (AREA)
- Algebra (AREA)
- Mathematical Physics (AREA)
- Pure & Applied Mathematics (AREA)
- Computer Hardware Design (AREA)
- Evolutionary Computation (AREA)
- Geometry (AREA)
- General Engineering & Computer Science (AREA)
- Electromagnetism (AREA)
- Measuring Volume Flow (AREA)
Abstract
The invention discloses an infrared flowmeter for measuring the real-time flow rate of emulsion, which relates to the field of emulsion real-time flow rate detection equipment, adopts a non-contact infrared flowmeter structure, and selects an infrared transmitting tube with the wavelength of 820nm as an infrared transmitter, so that the infrared transmitter can accurately detect the flow of large-particle milk and buffalo milk and the flow of small-particle goat milk and camel milk, and is more widely applied; the method has the advantages that the calculation algorithm of the emulsion flow is redesigned, the piecewise linear fitting mode is adopted, the measurement is accurate, the average error between the actual weighing data of the pasture and the metering data of the flowmeter is less than or equal to 5%, the production requirement that the error of the pasture is less than or equal to 10% can be completely met, the method can be realized by using a common single chip, the problem that the metering error of the original non-contact infrared flowmeter is large is solved, the manufacturing cost which is higher than the original price multiple times and is brought by a microprocessor with a floating point operation function is not needed to be replaced, the high performance is obtained at low cost, and the method is suitable for large-scale popularization and application.
Description
Technical Field
The invention relates to the field of emulsion real-time flow rate detection equipment, in particular to an infrared flowmeter for measuring the emulsion real-time flow rate.
Background
At present, a differential precise breeding mode is commonly adopted in the dairy cow breeding field, namely, feeds with different formulas are put in according to different milk yields of dairy cows for feeding. The method is characterized in that high-quality high-yield cows with high milk yield are fed with high-price concentrated feed, common cows with average milk yield are fed with common feed with low price, and sick cows with low milk yield or inferior cows waiting to be treated are fed with feed with low price. The differentiated accurate breeding mode can effectively improve the input-output ratio of cow breeding, and has high feed conversion rate and remarkable economic benefit.
The key point of the differential accurate breeding mode is that the milk yield of each dairy cow is accurately measured, and a high-precision milk flowmeter is urgently needed to complete the function. The working principle of the existing domestic milk flowmeter is contact type, wherein the turbine type and the positive displacement type are mainly adopted. Because milk is rich in nutrient components such as fat, protein and the like, deposited milk scale is easy to form on contact surfaces and is difficult to clean, and bacteria can be caused to grow so as to seriously influence the quality of the milk.
The non-contact metering mode is to install emitting/receiving parts on two sides of the milk conveying pipeline, to calculate the thickness of milk with the same concentration in the pipeline based on the attenuation or shift of the intensity, the shape, the flow rate, etc. of milk. The measuring mode can realize accurate measurement without contacting milk, has no movable parts and maintenance, has the advantages of convenient installation, simple structure, maintenance-free, high milk sanitary quality, accurate measurement and the like, and is the direction of milk measurement development in the future.
So far, a plurality of companies and scientific institutions at home and abroad have developed related research works and have achieved certain results. The non-contact milk flowmeter using infrared rays/ultrasonic waves as signals is developed and succeeded in China mainly in universities such as Shandong agriculture university, hebei agriculture university, inner Mongolia university and southeast university. Foreign companies such as Lilava, affalo and the like also respectively develop non-contact milk flow meters of the foreign companies, and the performance of the non-contact milk flow meters is basically consistent with that of domestic universities.
Although various non-contact milk flow meters have been developed at home and abroad, they all have certain problems, and significant improvements are required to meet the actual needs. Taking near infrared ray milk flow real-time detection system as an example of Shandong university Wang Mingjiang, the measurement result in the laboratory is excellent (the error is about 4%), but the error of actual milking for 4 times after entering pasture is about 8%, and the actual error is about 15% according to the result that we accumulate for 150 cows to measure in the pasture in multiple times in the field. The foreign company's products are also small in measurement errors of well-trained cows in pastures with good equipment, and are also large in pastures with unstable negative pressure or where cows are frequently stepped on milking devices.
Taking near infrared ray milk flow real-time detection system as an example of Shandong university Wang Mingjiang, the milk flow calculation formula is to directly multiply the cross-sectional area S of milk in the pipeline with a determined flow velocity value V to obtain an instantaneous flow value Q, and then to obtain the total milk yield Q of a single dairy cow through accumulation and summation. In general, under the condition of relatively thin pipelines and relatively low flow rates, the flow rates of various liquids such as water, oil, milk and the like are basically calculated. This calculation method has the advantage of being simple and fast, and has the disadvantage of not being very accurate. The actual flow velocity distribution of the milk in the pipeline is complex, and a single flow velocity value V cannot accurately reflect the actual flow velocity of the milk. After entering the milking device, the milk flows forwards in a negative pressure state, and after passing through the U-shaped pipe, the milk is in a plug flow state. After entering the flowmeter, the milk flow is firstly in an inlet effect (caused by the diameter change generated by the sleeving of the rubber tube) and then in a transient vortex state. Because milk contains high molecular particles such as fat and protein, internal friction exists in the flowing process. Under the combined action of negative pressure, gravity, internal friction and friction on the surface of the pipeline, the milk is in a completely turbulent state. There is no theoretical derivation formula for turbulent flow velocity distribution so far, and the existing approximate flow velocity distribution formula is summarized according to practical experience.
The detection system for Shandong university of agriculture is carefully analyzed, and the most main cause of the flow measurement error is found to be 2 points: firstly, the estimation of the milk flow rate is too simple and is not in accordance with the actual situation; secondly, the selected STM32F103RCT6 singlechip cannot directly carry out floating point operation, in is directly calculated according to an integer data processing formula, extremely high errors can be generated In a calculation result, and if a microprocessor MPU with a floating point operation function is selected, the price is several times higher than that of a common singlechip.
In addition, the existing infrared flowmeter is used for detecting milk flow, and once the infrared flowmeter is used for detecting other emulsions such as goat milk, buffalo milk, camel milk and the like, larger errors can be generated. The milk is a mixture, and mainly comprises water, protein, fat, lactose, calcium and other mineral substances and vitamins. Therefore, the structures of macromolecular substances such as protein, fat and the like and the proportion of various components in different animal emulsions are different, so that the existing infrared flowmeter has poor effect on measuring the goat milk with smaller protein and fat particles.
Disclosure of Invention
In order to solve the technical problems, the invention provides the infrared flowmeter for measuring the flow rate of the emulsion in real time, wherein a piecewise linear fitting algorithm is adopted for calculating the flow rate of the emulsion, so that logarithmic calculation of integer data is avoided while the calculation accuracy is ensured, the same application effect as that of an MPU chip is achieved, various emulsion flows can be accurately detected, and the applicability and the universality of the infrared flowmeter are expanded.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
An infrared flowmeter for measuring the real-time flow rate of emulsion is composed of non-contact infrared flowmeter, infrared transmitters/receivers installed to two sides of milk delivering pipeline, and algorithm program for calculating the flow rate of emulsion, wherein said infrared transmitter is an infrared signal transmitting tube with wavelength of 820nm, and said algorithm for flow rate of emulsion is implemented by piecewise linear fitting mode, and features that:
1) Using A4 paper to simulate milk layer filling flowmeter, measuring the relation between paper number and infrared shielding, wherein the paper number and infrared shielding attenuation basically have logarithmic relation, and using piecewise linear fitting mode to calculate the formula of emulsion thickness d
d＝aj+kj*U (1)
Wherein a j represents a constant coefficient value, k j represents the slope of a j-th fitting line segment, U represents a measured infrared signal attenuation value, fitting line segments with different slopes k j are selected according to different value range intervals of U, and when j is more than or equal to 4, the fitting precision error is smaller than 1 piece of paper;
2) Assuming that the emulsion is layered in units of the thickness of the A4 paper, the thickness of each layer of the emulsion is S 0, thereby obtaining a formula for calculating the flow rate of the emulsion
3) The calculation formula of the Reynolds number R e shows that the emulsion is in a complete turbulence state in a vertical closed flowmeter,
Wherein ρ represents the density value of the liquid, v represents the flow rate of the liquid, d represents the pipe diameter, μ represents the viscosity coefficient of the emulsion, the emulsion density is generally 1.038-1.040kg/m 3, the emulsion flow rate in the pipeline is generally in the range of 3-7m/s, the pipe diameter of the flowmeter is 8mm, the viscosity coefficient is generally 1.2-2.5cP, and the Reynolds number R e obtained after substituting the formula (3) is 9974-48487;
4) Obtaining the layering flow velocity distribution condition of the emulsion by taking the thickness of A4 paper as a unit according to an approximate flow velocity distribution formula in engineering practice,
Where u represents the flow rate of the liquid, u max represents the flow rate of the liquid at the very center of the pipeline, R represents the radius of the pipeline, R represents the distance from the very center of the pipeline, n is an index, the value of n depends on the reynolds number R e, and when n=1/7, the flow rate distribution conforms to the milk layering flow rate distribution in units of A4 paper thickness;
5) Substituting the distribution value of the layering flow velocity of the emulsion into the formula (2) to obtain an instantaneous flow value q (t), obtaining the corresponding relation between the instantaneous flow of the emulsion and the layering number, and obtaining an approximate calculation formula of the instantaneous flow of the emulsion by adopting a piecewise linear fitting mode for realizing rapid calculation
q(t)＝bh+kh×S (5)
Wherein b h represents a constant coefficient value, k h represents the slope of the h fitting line segment, S represents the emulsion layer value, and a fitting line segment with a constant coefficient of k h and a constant coefficient of b h is selected according to different layer number values;
6) Combining equation (5) with equation (1) to obtain equation
q(t)＝bh+kh×(aj+kj×U)/S0 (6)；
7) The formula (6) is processed and simplified to obtain the formula
q(t)＝bi+ki×U (7)
Wherein b i＝bh+kh×aj÷S0,ki＝kh×kj÷S0 directly reflects the approximate correspondence between the instantaneous flow and the infrared signal attenuation value.
The measurement weight w j is introduced into the emulsion flow algorithm to describe the frequency of occurrence of the infrared signal attenuation, and the minimum y value constraint in the formula (8) needs to be satisfied when the coefficients b i and k i in the formula (7) are calculated
y＝∑wj||q(t)-bi-ki×U||2 (8)。
The infrared flowmeter is vertically installed, the inclination angles of the infrared flowmeter are all smaller than 15 degrees, and the upper interface and the lower interface of the infrared flowmeter are required to be connected with a straight pipe which is not shorter than 20cm and then connected with an emulsion circulation bend or elbow.
According to the invention, a non-contact infrared flowmeter structure is adopted, and an infrared transmitting tube with the wavelength of 820nm is selected as an infrared transmitter, so that the infrared transmitter can accurately detect the flow of large-particle milk and buffalo milk, and accurately detect the flow of small-particle goat milk and camel milk, and is more widely applied; the method has the advantages that the calculation algorithm of the emulsion flow is redesigned, the piecewise linear fitting mode is adopted, the measurement is accurate, the average error between the actual weighing data of the pasture and the metering data of the flowmeter is less than or equal to 5%, the production requirement that the error of the pasture is less than or equal to 10% can be completely met, the method can be realized by using a common single chip, the problem that the metering error of the original non-contact infrared flowmeter is large is solved, the manufacturing cost which is higher than the original price multiple times and is brought by a microprocessor with a floating point operation function is not needed to be replaced, the high performance is obtained at low cost, and the method is suitable for large-scale popularization and application.
Drawings
FIG. 1 is a diagram showing the relationship between the number of sheets and the infrared shielding in an A4 sheet simulated milk layer experiment;
FIG. 2 is a schematic illustration of the relationship diagram of FIG. 1 after piecewise linear fitting;
FIG. 3 is a schematic diagram of the stratified flow velocity distribution of an emulsion;
FIG. 4 is a schematic diagram showing the relationship between the instantaneous flow rate of emulsion and the number of layers;
FIG. 5 is a graph of piecewise approximate linear relationship between the instantaneous flow of emulsion and signal decay;
Fig. 6 is a schematic diagram of measurement weight values.
Detailed Description
The invention is described in detail below with reference to the attached drawings and the specific embodiments:
The invention structurally adopts a non-contact infrared flowmeter structure, infrared emission/receivers are respectively arranged at two sides of a milk pipeline, and the real-time flow of the emulsion is calculated through a set algorithm program. It will be appreciated by those skilled in the art that all mammalian emulsions are mixtures of various substances such as water, protein, fat, lactose, etc., and that emulsions of different animals are distinguished by the molecular structure and ratio of the components of the various substances. The protein particles and fat particles of goat milk and camel milk are smaller in size and the wavelength of the infrared signal required for detection should be shorter than those of cow milk. Milk contains a large amount of high molecular groups, the absorption spectrum of the milk is mainly concentrated in the wavelength region of 700-1100nm, and the infrared flowmeter at present generally selects 940-960nm wavelength infrared signal emitting tubes [1,8] which are popular in the market. The infrared emission tube with shorter wavelength and 820nm is adopted in the invention, and the infrared emission tube does not influence the detection of milk in the wavelength range of 700-1100nm, is also suitable for detecting the flow of various emulsions such as goat milk, camel milk and the like rich in smaller particles, and expands the applicability and universality of infrared flowmeter.
According to the analysis of the milk metering algorithm, the cross-sectional area S of milk is combined with the distribution characteristic of the approximate flow velocity, so that the calculated flow value and the actual measured value are more consistent, the error between the calculated flow value and the actual measured value is obviously reduced, the actual requirement of pasture emulsion production can be completely met, and the real-time flow algorithm of the emulsion is adjusted in a piecewise linear fitting mode.
The algorithm of the emulsion flow adopts a piecewise linear fitting mode, avoids logarithmic calculation of integer data, can be realized by adopting a common single chip microcomputer, solves the problem of measurement precision, and greatly reduces the manufacturing cost.
1) Simulating a milk layer filling flowmeter by using A4 paper, wherein the relation between the measured paper number and the infrared shielding is shown in figure 1, the paper number and the infrared shielding attenuation are basically logarithmic, the formula for calculating the thickness d of the emulsion is shown in figure 2 by adopting a piecewise linear fitting mode
d＝aj+kj*U (1)
Wherein a j represents a constant coefficient value, k j represents the slope of a j-th fitting line segment, U represents a measured infrared signal attenuation value, fitting line segments with different slopes k j are selected according to different value range intervals of U, and when j is more than or equal to 4, the fitting precision error is smaller than 1 piece of paper.
2) Assuming that the emulsion is layered in units of the thickness of the A4 paper, the thickness of each layer of the emulsion is S 0, thereby obtaining a formula for calculating the flow rate of the emulsion
3) The emulsion is mainly subjected to the action of gravity, negative pressure, internal friction and pipeline friction in a vertical installed closed flowmeter. Considering the influence of emulsion viscosity and pipeline friction, an adhesive surface layer is formed on the inner surface of the pipeline, the emulsion flow rate of the adhesive surface layer is extremely low, so-called wall hanging is formed, and the Reynolds number R e is a parameter for judging the flowing state of viscous fluid. The calculation formula of the Reynolds number R e shows that the emulsion is in a complete turbulence state in a vertical closed flowmeter,
Wherein ρ represents the density value of the liquid, v represents the flow rate of the liquid, d represents the pipe diameter, μ represents the viscosity coefficient of the emulsion, the density and viscosity coefficient of the emulsion are related to the water content of the emulsion, the density of the emulsion is generally 1.038-1.040kg/m 3, the flow rate of the emulsion in a pipeline is generally in the range of 3-7m/s because of different negative pressure value settings, the pipe diameter of a flowmeter is 8mm, the viscosity coefficient is generally 1.2-2.5cP, and the Reynolds number R e obtained after substituting the formula (3) is 9974-4848487 and far exceeds the transition area value 4000, so that the emulsion is in a completely turbulent state.
4) At present, no theoretical formula for turbulent flow velocity distribution exists, and an approximate flow velocity distribution formula can be obtained only empirically. The relevant literature shows that under similar conditions, the higher the flow rate of the liquid in the center of the pipeline, the lower the flow rate closer to the pipeline wall, and the flow rate in the pipeline wall is rapidly close to 0, according to the approximate flow rate distribution formula in engineering practice, the layered flow rate distribution of the emulsion in units of A4 paper thickness is obtained,
Where u represents the flow rate of the liquid, u max represents the flow rate of the liquid at the very center of the pipe, R represents the pipe radius, R represents the distance from the very center of the pipe, n is an index, the value of n depends on the reynolds number R e, and when 4×10 3≤Re＜1.1×105, n=1/6; when 1.1×10 5≤Re＜3.2×106, n=1/7; when 3.2×10 6≤Re, n=1/10. It was verified that when n=1/7, the milk stratified flow velocity distribution in A4 paper thickness is satisfied as shown in fig. 3.
5) Substituting the distribution value of the layering flow velocity of the emulsion into the formula (2) to obtain an instantaneous flow value q (t), obtaining the corresponding relation between the instantaneous flow of the emulsion and the layering number as shown in figure 4, and obtaining an approximate calculation formula of the instantaneous flow of the emulsion by adopting a piecewise linear fitting mode for realizing rapid calculation
q(t)＝bh+kh×S (5)
Where b h represents a constant coefficient value, k h represents the slope of the h fitted line segment, S represents the emulsion layer value, and a fitted line segment with a constant coefficient of k h and b h is selected according to different layer number values.
6) Combining equation (5) with equation (1) to obtain equation
q(t)＝bh+kh×(aj+kj×U)/S0 (6)。
7) The formula (6) is processed and simplified to obtain the formula
q(t)＝bi+ki×U (7)
Wherein b i＝bh+kh×aj÷S0,ki＝kh×kj÷S0 directly reflects the approximate corresponding relation between the instantaneous flow and the infrared signal attenuation value as shown in figure 5, and realizes high-precision emulsion flow calculation without executing integer data logarithmic operation with larger error.
In order to further reduce the error generated by the approximation calculation, as a preferred mode, a measurement weight w j is introduced into the emulsion flow algorithm to describe the frequency of occurrence of the infrared signal attenuation, the value of w j is as shown in fig. 6, and the minimum constraint of the y value in the formula (8) needs to be satisfied when coefficients b i and k i in the formula (7) are calculated
y＝∑wj||q(t)-bi-ki×U||2 (8)。
Preferably, the infrared flowmeter is vertically installed, the inclination angles of the infrared flowmeter are all smaller than 15 degrees in the front-back and left-right directions during installation, and the upper interface and the lower interface of the infrared flowmeter are connected with straight pipes which are not shorter than 20cm, and then are connected with emulsion circulation bends or elbows.
The infrared flowmeter designed by the invention follows the fluid mechanics model of an ideal state, so that strict installation requirements are met. The flowmeter of the invention must be installed vertically, the inclination angle of the front, back, left and right is less than 15 degrees, the upper interface and the lower interface of the flowmeter must be connected with the rear of a straight pipe which is not shorter than 20cm, and a bend or an elbow can be connected. Because the ideal model only considers the effects of emulsion gravity and negative pressure, ignoring the influence of the slope of the pipe wall, the flowmeter is required to be installed vertically. Because the length of the pipeline of the flowmeter is short, the error between the actual flow rate and the theoretical flow rate is small when the inclination angle is smaller than 15 degrees, and the actual flow rate and the theoretical flow rate can be approximately considered to be consistent. Because the flow velocity distribution of the emulsion is readjusted when the emulsion flows through the elbow or the bent pipe, a short vortex is formed. After the emulsion flows through the 20cm straight pipe connected with the upper interface, the emulsion is restored to a state that the flow velocity distribution is relatively stable, and the error of flow calculation can be reduced. The elbow or bend connected to the lower part of the flowmeter also reduces the flow rate of the emulsion, which results in the outlet flow rate of the elbow or bend being less than the inlet flow rate, resulting in a blockage. The 20cm straight pipe connected with the lower part of the flowmeter can be used as a buffer area to prevent emulsion from blocking to an infrared measurement area and avoid measurement errors.
It should be understood that the above description is not intended to limit the invention to the particular embodiments disclosed, but to limit the invention to the particular embodiments disclosed, and that the invention is not limited to the particular embodiments disclosed, but is intended to cover modifications, adaptations, additions and alternatives falling within the spirit and scope of the invention.
Claims (3)
1. The infrared flowmeter for measuring the real-time flow rate of the emulsion adopts a structure of a non-contact infrared flowmeter, infrared emission/receivers are respectively arranged on two sides of a milk conveying pipeline, and the flow rate of the emulsion is calculated through a set algorithm program.
1) Using A4 paper to simulate milk layer filling flowmeter, measuring the relation between paper number and infrared shielding, wherein the paper number and infrared shielding attenuation basically have logarithmic relation, and using piecewise linear fitting mode to calculate the formula of emulsion thickness d
d＝aj+kj*U (1)
Wherein a j represents a constant coefficient value, k j represents the slope of a j-th fitting line segment, U represents a measured infrared signal attenuation value, fitting line segments with different slopes k j are selected according to different value range intervals of U, and when j is more than or equal to 4, the fitting precision error is smaller than 1 piece of paper;
2) Assuming that the emulsion is layered in units of the thickness of the A4 paper, the thickness of each layer of the emulsion is S 0, thereby obtaining a formula for calculating the flow rate of the emulsion
3) The calculation formula of the Reynolds number R e shows that the emulsion is in a complete turbulence state in a vertical closed flowmeter,
Wherein ρ represents the density value of the liquid, v represents the flow rate of the liquid, d represents the pipe diameter, μ represents the viscosity coefficient of the emulsion, the emulsion density is generally 1.038-1.040kg/m 3, the emulsion flow rate in the pipeline is generally in the range of 3-7m/s, the pipe diameter of the flowmeter is 8mm, the viscosity coefficient is generally 1.2-2.5cP, and the Reynolds number R e obtained after substituting the formula (3) is 9974-48487;
4) Obtaining the layering flow velocity distribution condition of the emulsion by taking the thickness of A4 paper as a unit according to an approximate flow velocity distribution formula in engineering practice,
Where u represents the flow rate of the liquid, u max represents the flow rate of the liquid at the very center of the pipeline, R represents the radius of the pipeline, R represents the distance from the very center of the pipeline, n is an index, the value of n depends on the reynolds number R e, and when n=1/7, the flow rate distribution conforms to the milk layering flow rate distribution in units of A4 paper thickness;
5) Substituting the distribution value of the layering flow velocity of the emulsion into the formula (2) to obtain an instantaneous flow value q (t), obtaining the corresponding relation between the instantaneous flow of the emulsion and the layering number, and obtaining an approximate calculation formula of the instantaneous flow of the emulsion by adopting a piecewise linear fitting mode for realizing rapid calculation
q(t)＝bh+kh×S (5)
Wherein b h represents a constant coefficient value, k h represents the slope of the h fitting line segment, S represents the emulsion layer value, and a fitting line segment with a constant coefficient of k h and a constant coefficient of b h is selected according to different layer number values;
6) Combining equation (5) with equation (1) to obtain equation
q(t)＝bh+kh×(aj+kj×U)/S0 (6)；
7) The formula (6) is processed and simplified to obtain the formula
q(t)＝bi+ki×U (7)
Wherein b i＝bh+kh×aj÷S0,ki＝kh×kj÷S0 directly reflects the approximate correspondence between the instantaneous flow and the infrared signal attenuation value.
2. The infrared flowmeter for real-time flow rate metering of emulsion of claim 1, wherein the emulsion flow algorithm incorporates a measurement weight w j to describe the frequency of occurrence of infrared signal attenuation, the coefficients b i and k i in equation (7) being calculated to satisfy the constraint of minimum y in equation (8)
3. The infrared flowmeter for measuring the real-time flow rate of emulsion according to claim 1, wherein the infrared flowmeter is vertically installed, the inclination angles of the infrared flowmeter are all less than 15 degrees in front, back, left and right directions during installation, and the upper interface and the lower interface of the infrared flowmeter are connected with straight pipes which are not shorter than 20cm, and then are connected with a circulation bend or elbow of the emulsion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210483445.4A CN114812709B (en) | 2022-04-25 | 2022-04-25 | Infrared flowmeter for real-time flow rate measurement of emulsion |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210483445.4A CN114812709B (en) | 2022-04-25 | 2022-04-25 | Infrared flowmeter for real-time flow rate measurement of emulsion |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114812709A CN114812709A (en) | 2022-07-29 |
| CN114812709B true CN114812709B (en) | 2024-07-12 |
Family
ID=82510850
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210483445.4A Active CN114812709B (en) | 2022-04-25 | 2022-04-25 | Infrared flowmeter for real-time flow rate measurement of emulsion |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114812709B (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN217210994U (en) * | 2022-04-25 | 2022-08-16 | 山东成城物联网科技股份有限公司 | Near infrared non-contact raw milk flow meter |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3798383B2 (en) * | 2003-04-03 | 2006-07-19 | オリオン機械株式会社 | Data communication method and milking unit automatic detachment device in milking management system |
| DE102004048736A1 (en) * | 2004-10-05 | 2006-04-06 | Westfaliasurge Gmbh | Device and method for measuring milk quantity, in particular during the milking process |
| CN204259564U (en) * | 2014-12-01 | 2015-04-15 | 世牧农业科技(上海)有限公司 | A kind of infrared type milk volume flow monitoring device |
| CN104365486B (en) * | 2014-12-01 | 2016-08-17 | 世牧农业科技(上海)有限公司 | A kind of method monitoring milk volume flow |
| CN108401913B (en) * | 2018-01-25 | 2021-01-26 | 李冬至 | Device and method for detecting milk flow on line |
-
2022
- 2022-04-25 CN CN202210483445.4A patent/CN114812709B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN217210994U (en) * | 2022-04-25 | 2022-08-16 | 山东成城物联网科技股份有限公司 | Near infrared non-contact raw milk flow meter |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114812709A (en) | 2022-07-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4331025A (en) | Methods of measuring fluid viscosity and flow rate | |
| CN206930321U (en) | Non-full pipe ultrasonic flowmeter | |
| CN204255415U (en) | Tapered hole plate type gas-liquid two-phase flowmeter | |
| CN101189508A (en) | Method and ultrasonic meter system for determining pipe roughness | |
| AU2016359472A1 (en) | A stratified flow multiphase flowmeter | |
| CN102288235A (en) | Double-track mixed type ultrasonic flowmeter and measuring method | |
| CN105157771A (en) | Time difference type supersonic wave flow measuring method and device | |
| CN104236653B (en) | A kind of method that light-end products mass flow measurement is carried out with ultrasonic wave | |
| CN1182873A (en) | Three-phase flow meter for oil, gas and water and measuring method thereof | |
| CN111351540A (en) | Method and system for detecting mass flow rate of particles in pneumatic conveying process | |
| CN114812709B (en) | Infrared flowmeter for real-time flow rate measurement of emulsion | |
| CN201493963U (en) | Additive metering system of cement concrete mixing equipment | |
| TWI304472B (en) | ||
| CN204514397U (en) | A kind of non full package flow measurement device | |
| CN206291930U (en) | A kind of ultrasonic wave mass flowmenter | |
| CN106932476A (en) | A kind of device and method for measuring solid-liquid two-phase flow phase content | |
| CN208536933U (en) | A kind of discontented metering ultrasonic flowmeter of plug-in type | |
| CN202304909U (en) | Cleanable through-type W reflection-type ultrasonic tube section structure | |
| CN208092077U (en) | A kind of feedwater piping flow rate measuring device | |
| CN103791960B (en) | A kind of method of reduction furnace flow accurate measurement | |
| CN110567543A (en) | channel flow measuring equipment | |
| CN2277514Y (en) | Three-phase flow measuring unit for oil, gas and water | |
| CN107505476B (en) | Mean flow flow velocity measuring system in a kind of linear distance | |
| CN202024840U (en) | Heat meter for measuring heating quantity | |
| Waluś | Mathematical modelling of an ultrasonic flowmeter primary device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |