TW200411146A - Jet flow meter - Google Patents

Abstract

There is provided a jet flow meter, which includes the following three major parts: a buffer chamber, a micro channel and a fluid oscillating chamber. The buffer chamber is provided to make the fluid smoothly enter the jet flow meter from the flowing field. Then, fluid enters the micro channel from the buffer chamber. The micro channel has multi-threaded micro flow elements for detecting the flowing field of micro flow. Finally, fluid enters the fluid oscillating chamber from the micro channel. When the Renault number of flowing field reaches the status of transition flow, the fluid becomes unstable. By measuring the frequency of fluid oscillation, it is able to derive the flowing fields of middle and high flows. This jetflow meter is combined with the micro flow and the measurement of middle and high flows to expand the dynamic measurement range of the flow meter.

Description

200411146

V. Description of the invention (1) [Technical field to which the invention belongs] The present invention relates to a jet flow meter, which is applied to flow measurement in a flow field. [Prior art] current meter wide range of applications, for example: each family will use the gas to daily life ,, table tongue, beer aspirator used in the hospital of the gas flow control, automotive air-conditioning Flowmeters are used in gas generators, laboratories or & factories. However, for applications in different fields, there will be different flow measurement ranges. The currently developed flowmeters are mainly used in gas meters to make a brief introduction to the different types of flowmeter structures and their measuring principles. 〇) Jet shock flowmeters proposed in US Patent No. 4,244, 230, Please refer to "Figure 1". First, a high-aspect-ratio flow channel is formed at the inlet of the fluid. The cross-sectional shape of this flow channel is narrow and deep, so that the fluid flowing through it forms a surface. Fluid squirting out. When the household comes, when the outlet 20 gradually shrinks to a gradually wider place, because ;; = 于 二 = the groove 31 of the body 30 will cause the phenomenon of fluid instability, and the production :: effect will cause the fluid to sway At the moment when the fluid exits from the outlet ^, the fluid may swing to the left or to the right, = the effect. The '^ f sensor 40' is provided on the left and right sides of the groove 31 because the fluid shock sensor 4 = rate: linear relationship with the volumetric flow rate of the fluid, so; rate. The greater the flow resistance, the better; the better the political result, and the better the effect of the fluid shock sensor 4 = 200411146 V. Description of the invention (2) 'This patent is provided with a blocking body at the front end of the fluid outlet 20. 30 to increase fluid instability. The disadvantage of the present invention is that the fluid resistance must be exchanged for a significant shock effect 'and that there must be sufficient pressure loss to cause the fluid shock effect. (2) disclosed by the U.S. Patent of the 5,3 6,8 0 9 9 flowmeter shown refer to "FIG. 2", the design principle of the same patent, but the aforementioned patent biggest difference The reason is that this patent adds a fluid oscillating sensor 40 in the middle of the groove 31 of the oscillating chamber. Its main function is to improve the resolution of fluid oscillating sensing, especially when the fluid flow is small and the oscillating is not very When it is obvious, it can effectively improve and improve the accuracy of the flow meter. (3) disclosed in U.S. Patent No. 6 5,3 3,7 0 of the first flow meter 4, shown refer to "FIG. 3", the main purpose of this patent is to improve U.S. Patent No. 5,3 96, the disadvantage of the disclosed flowmeter 80 · 9 because when the fluid flow rate becomes faster, although the effect of the fluid shocks better, but it will generate a vortex disorder (v 〇rte X) in the recess 31, the fluid 31 will flow over this recess became more chaotic, thus influencing the fluid shock sensor 40 measuring the amount of to-noise ratio becomes inconspicuous. Therefore, this patent is to improve this disadvantage, it is on both sides of each recess 31 digging a bypass passage (B ypass) 3 2, so that full flow recess 31 may be generated by the bypass passage 32 flows, reducing the groove 31 Turbulent flow of the internal fluid to increase the signal-to-noise ratio of the fluid when it oscillates. (4) According to U.S. Patent No. 5, 157, 974 disclosed the size of the gas meter microcomputer, refer to "FIG. 4", the core technology is the fluidic flowmeter, the flowmeter is applied to the gas jet table The biggest advantage is that the gas is basically not very clean and it is easy to accumulate impurities in the flowmeter structure.

Page 6 200411146 V. Description of the invention (3) And the jet flow meter can be used. 丨 Field, go ^ to make the flow meter measurement =: =: Zhen Sheng used to clean the inside of the gas meter, and the profit sensor 40 was placed in the flow channel. . This jet flow meter is due to the flow path 5 when the fluid is shaken. Burst: at the mouth of m 'when the fluid passes through the flow channel 50 signal to calculate the fluid; the patented invention measured by the fluid oscillating f-detector 40 is different from the flow that can be different. When this phenomenon of fluid turbulence occurs, the second :: is to avoid the weakening of the patented invention but also another disadvantage ′. Therefore, this patent proposes and significantly improves the noise-to-noise ratio. The work is not effective (;) "L is shown in the figure / benefit, the flowmeter disclosed in T'2_9, please refer to 5w" The structure design is roughly the same as that disclosed in US Patent No. 157, 9 74 The miniaturized microcomputer gas meter is the same. The main idea is to set the fluid shock sensor 40 at the entrance of the shock chamber 60a. The main purpose is to increase the frequency of sensing fluid shock = 2. But this patent The disadvantage is that as long as the pressure in the upstream flow field changes, this will become the iron judgment of δίΐ and cause inaccurate flow field measurement. 2) For the flow chart of the flowmeter disclosed in Japanese Patent No. JP20 0 1 -20 8 575, please refer to "Figure 6" for the three-dimensional structure of the flowmeter. The basic principle of this patent again utilizes the phenomenon of fluid instability. To estimate the mass flow rate of the fluid. The $ grading section 70 first causes the acceleration of the fluid, and then creates a so-called approximately two-dimensional flow field through the high-aspect-ratio flow channel to generate a fluid instability phenomenon, and the gray body is periodically oscillated to achieve fluid metering. Functions. However, this patent 200411146 V. Description of the invention (4) has the same disadvantages as the flowmeter disclosed in the aforementioned Japanese Patent No. JP4-262209: This flowmeter is easily affected by the pressure of the upstream flow field, which causes the vibration gas to be sensed. The error. In these flowmeters, the measurement range is quite limited, and a large flow range cannot be measured. In addition, when the micro-flow field needs to be measured, the diameter of the pipe used must be reduced accordingly. This will cause a large pressure loss.

And 'Currently, the measurement range of general household flow meters is from 0.3 liters / hour to 3 0 0 liters / hour, and its dynamic measurement range ((^ 11 & 111 丨 (^ 1 ^ 11)) reaches 1 0 0 0 0: 1, however, there is no single flowmeter that can measure such a large range of the flowmeters currently developed. [Contents of the Invention] The dynamic quantities of 莶 π or more jet flowmeters for measuring sensing elements Testing the flow channel in the flushing chamber and micro-channel flowmeter of the present invention, and the problem of the frequency-recognized technology that generates unstable fluid shock when the Reynolds number of the micro-flow channel and the micro-flow reaches the 'the purpose of the present invention is to provide First, it combines micro-pipes for measuring micro-flow and multi-line micro-flows and fluid oscillators for measuring medium and high-flow to achieve a larger circumference.

Fluidic flowmeter, which comprises three main parts: the slow and fluid shock room. The buffer chamber is such that a multi-line micro-flow sensing element is provided in the micro-flow connected to the fluid to enter the fluid smoothly into the fluid flow. Finally, the fluid enters the fluid oscillating chamber in winter. 〇w): the phenomenon of diarrhea, which causes the fluid to oscillate. Using the measurement rate, you can estimate the measurement of medium and high flow fluids.

200411146 V. Description of Invention (5)

The jet flowmeter developed by the present invention has the following advantages: (1) Unlike ordinary gas flowmeters, there is no movable element inside the jet flow, so it will not cause measurement due to long-term use. Error, and the resulting pressure loss is small. (2) the fluid portion of the shock chamber for measuring high flow, which flow measurements for different types of liquids, the measurement results simply multiplied by a correction factor (i.e., the density of the liquid) flow can be obtained which, There is no need to replace different floats according to different liquids like ordinary float flow meters, which is convenient for users to operate and greatly improves the measurement accuracy. In addition, the shock generated when the fluid in the fluid chamber of the shock, the host can remove dirty meter

West Province, in order to maintain accuracy in measurement. (3) Since this jet flow meter uses a multi-line flow sensing element in conjunction with the time-of-flight (T ime ff 1 i gh t) principle when measuring micro-flow, it can accurately measure The instantaneous velocity of the fluid. (4) The multi-line micro-flow sensing element provided in the micro-pipe of the present invention and the single-line fluid vibration sensing element used in the fluid oscillating chamber are made of polycrystalline silicon material, so it has low power consumption, High sensitivity and easy integration with complementary metal oxide semiconductor (CMOS) circuits. (5)-The flowmeters that are generally seen usually generate a great pressure loss in the fluid, but the jet flowmeter of the present invention is well-known by, * from μ ^ 1 α ^ person * L, the body knows Lightweight and low cost, 1 directly connected in the pipeline without causing piezoresistance in the pipeline. (6) The jet flow meter of the present invention is applied to a film-type gas meter, because of its mechanical or clustering, it can eliminate the friction resistance or ϊ of the S ^ module.

200411146 V. Description of the invention (6) Internal leakage caused by gaps. [Embodiment] The jet flowmeter developed by the present invention is installed in the flow field to measure the fluid flow in the flow field. For the top view, please refer to "Figure 7", which includes three main parts Parts ... buffer chamber 80, microchannel 90, and fluid morning surplus to 100. The main function of the buffer chamber 80 is to stabilize the flow field flowing into the jet flow meter, so that it flows smoothly into the jet flow meter, instead of directly rushing into the microchannel 90, so as not to affect the measurement. result. In the micro-channel portion 9 billion, primarily provided by some of the sensing elements in the micro-channel 9〇, the measured amount of fluid in the micro flow; 9〇 micro channel when the sensing element is not sensing when measuring the flow rate of fluid, then by sEISMIC = 1 thousand and surplus chamber connected thereto to the amount of fluid in the high flow rate measurement. So, this jet flow = not only measures the flow field of micro flow, but also the flow field of medium and high flow, which covers a wider dynamic measurement range than the conventional flow meter. In the buffer chamber 80, which includes a first inlet 81, 'an outlet 82, and a stopper 5 and 83 disposed adjacent the first inlet 81, the fluid from the first inlet 81 into the buffer chamber 80, and With the arrangement of the blocking body 83, the fluid can smoothly enter the buffer chamber 80 without being flushed directly into the microchannel 90. The micro-flow channel 90 is connected to the first outlet 81 of the buffer chamber 80 to allow fluid to flow therein, and the place where the first outlet 81 is connected to the micro-flow channel 90 is a tapered tube type, which automatically accelerates the fluid to flow through the micro-flow Road 90. A multi-line micro-flow sensing element 9 丨 is set in the micro-fluidic channel 90, and the micro-fluid can be measured by measuring the time of flight (Tlme n UM) of the fluid. Please refer to "Figure 8", this multi-line micro flow sensor 91

Page 10 200411146 V. Description of the invention (7) It consists of several sensing elements. When the fluid flows into the microfluidic channel 90, the first sensing element it touches is a heater 9 1 a, and a temperature sensing element 91 b at a different distance from the heating element 9 1 a is disposed downstream thereof, and when the flow velocity of the fluid is changed, the temperature sensing element 9 1 b at a different position can sense its velocity.

The principle of measuring the flow rate of fluid is: the heating element 9 1 a is heated instantaneously for a period of time, and the heat wave generated on the heating element 9 1 a will move downstream with the movement of the fluid, and the micro-flow The temperature sensing element 9 1 b downstream of the channel 90 will sense the heat wave. Since when setting this temperature sensing element 9 jb, we know the distance between each temperature sensing element 9 1 b and the heating element 9 1 a, and also know the heating element 9 1 a heating and temperature sensing element 9 1 b The time difference in the middle of the heat wave is sensed. In this way, the flow velocity of the fluid can be calculated, and the flow rate of the fluid can be calculated. The fluid oscillating chamber 100 includes a second inlet 101, a second outlet 102, and two symmetric obstacles 103. The second inlet 101 is connected to the other end of the microchannel 90, so that the fluid flows into the fluid oscillating chamber 100, and the second outlet 102 is in communication with the flow field.

This provided an obstacle 〇3 purpose is this turbulence fluid chamber Shu thousand and two reserved segment to bypass flow passage Shu 〇4, respectively, by the fluid adjacent the second outlet via a bypass flow passage which two reserved 104 〇2 along the outer edge of this obstacle 103 and return to the second entrance 101; and one of the obstacles 103, or two obstacles 103 can be provided with a single line type fluid shock sensing elements 103a-line type fluid shock Sheng this sensing element is a pressure sensor based ma. When the fluid enters the fluid oscillating chamber 100 from the microfluidic channel 90, if the fluid flows at this time

200411146 Invention description (8) 2 The number of fields reaches the state of transitional flow (that is, the flow of fluid reaches the middle and high flow). The starvation body will produce instability, which is the Kongda effect. This effect ^ makes the jet flowing in from the second inlet 101 to oscillate left and right, and the fluid flowing through the two feedback side passages 104 can excite the jet to oscillate stably and continuously.田 此 嗔 'When the shock is flowing to the right or shaking to the left, the single-line penalty set on the obstacle 10 3 ^ ^ ^, 晨, 长,, 〃IL body morning swing sensing element 1 0 3 a will obviously feel It is detected that the body version comes over (because if there is no fluid swinging over, the fluid flow will be

Very small because the single-line fluid vibration sensing element 1 03a is a pressure sensor, because jf, & b can be sensitively sensed for the presence or absence of fluid, so refreshing, > ^ It can effectively reduce the signal-to-noise ratio and improve the accuracy of the flow meter. The present invention is designed as a tapered tube at the second outlet 102 of the fluid oscillating chamber 100. λ ^ aj,, ° It can start to oscillate at small flows. ★, = 1 Shu mesh technique before θ 'we know: of the flow field generated by the orifice effect white / frequency and volume flow rate of the fluid guar morning spirits linear relationship, thus, can be drawn by a single wire # _ ^ The vibration of the jet flow measured by the jin, claw body morning swing sensor 1 〇3a

Second; hept gp 5 lb fluid volume flow rate, and then multiply this volume flow rate by the fluid's degree to get the mass flow rate of the fluid. When the poise I ht. ^ ^ ^ Of the fluid is small, since the Reynolds number of the flow field has not reached the state of 31 t at this time, the fluid oscillation chamber 100 will not undergo fluid oscillation treatment ^ 'At this time the fluid The flow rate is measured by a multi-line micro-element 91 in the micro-channel 90. When the flow in the flow field reaches medium to high flow ^ I7 "The number of fields has reached the state of transitional flow), taking air as an example, when the flow velocity

Page 12 200411146 V. Description of the invention (9) When the fluid flow in the fluid vibration chamber 100 is opened at two minutes, the fluid will be opened. The phenomenon of the phenomenon "1" will be changed to the fluid shock chamber 1 〇〇 所 2 = Swing frequency, calculate the instantaneous volume flow rate at that time, and then convert it to instantaneous flow rate by using the squaring program. = L developed the present invention, this fluidic flowmeter dynamic fluid flow measurement range than the field of measurement with medium and small flow Chan 'and simple mechanical structure, the float met flowmeters used in size, thus' direct Connected in the flow field pipeline. Xi spar portion in the flow sensing element >, the material which is used platinum suspicious' made out of the heating elements, temperature sensing low power consumption, and high sensitivity and ease of integration with a complementary passage of Rong + characteristic. 7 Complementary golden lice + conductor meter gas i ν: Jet flowmeter has a wide range of applications, such as: gas, U; measure the instantaneous flow of fluid in the flow field. It ’s not the upper limit stated that the author is only %% of the best examples of this, and the equivalent changes made around it are all those who apply for patents according to the present invention] temple branching and dance, both are Covered by the patent scope of the present invention. 200411146 Brief description of the diagram. Figure 1 is a schematic diagram of a conventional jet oscillating flowmeter. Figure 2 is a schematic diagram of a conventional flowmeter. Figure 3 is a schematic diagram of a conventional flowmeter. Figure 4 is a conventional small-sized flowmeter. Structure of a chemical microcomputer gas meter. Figure 5 is a schematic diagram of a conventional flow meter. Figure 6 is a schematic diagram of a conventional flow meter. Figure 7 is a top view of a jet flow meter of the present invention. Schematic diagram of the microchannel of the present invention. [Illustration of Symbols]

Page 14 10 Inlet 20 Outlet 30 Barrier 31 Groove 32 Side Channel 40 Fluid Shock Sensor 50 Flow Channel 6 0a Oscillation Chamber Entrance 60b Oscillation Chamber Entrance 70 Tapered Section 80 Buffer Chamber 81 First Entrance 82 First Exit 83 Block 90 Micro-tube 200411146 Simple illustration 91 91a 91b 100 101 102 103 103a 104 Multi-line micro-flow sensing element heating element temperature sensing element fluid oscillating chamber second entrance second exit obstacle early linear fluid oscillation sensing Component feedback side channel

Page 15

Claims (1)

200411146 6. The scope of the patent application measures the flow field in the flow field. A jet flow meter is installed in the first-class field to measure the flow rate of the fluid, and includes: a buffer chamber, which includes a first damping bucket, an outlet and a stopper body floor near the brother an inlet of the fluid from this decision - entrance to the buffer chamber, and by JJ the stop member of and ρ bearing persons EDITION heart ju station and one thousand cis and out of the buffer chamber; A micro-flow channel connected to the first outlet of the buffer chamber to accelerate the flow of the fluid, and a multi-line micro-flow sensing element is provided in the micro-flow channel; and a fluid display chamber including: a second inlet and a second outlet, the first inlet and the other end of the micro channel is connected, and the second outlet in communication with the flow field 'and the fluid chamber is provided with two opposite shock referred obstacle, and The fluid oscillating chamber is partitioned to form two feedback side channels', and the fluid returns to the second inlet via the two feedback side channels along the outer edges of the two obstacles adjacent to the second outlet; The obstacle Was provided with a single line type fluid shock sensing element, when the fluid flows into the feedback type fluid shock chamber, since ^ of 2 corresponding action causes the fluid forms a jet of right and left shock 'by 3 single through each of the feedback The fluid in the side flow channel stabilizes the jet flow. 5 ^ < The shock of the jet flow measured by the linear fluid oscillating sensing element is used to estimate the flow rate of the fluid, and the fluid passes through the second Outlet / 1 flow flow meter; and the multi-line micro-flow sensing element you Η Λ Xi fluid ^ θ β years, that is, the destroyed fluid, when it is unable to measure the flow of the fluid . 2 · Jet weight as described in item 1 of the scope of patent application Page 16 The oscillating frequency of the jet measured in the oscillating chamber is estimated at 3: ^ and the other is 200411146 Sixth, the scope of patent application: 〆The single P early obstruction is also provided with the single-line fluid vibration sensing element ′, to estimate the vibration frequency of the jet measured by the linear fluid vibration sensing element and the flow rate of the fluid. From Dream First 3 · The jet flowmeter described in item 1 of the scope of patent application, the μ outlet is a type of tapered tube. ^^ First 4. The jet flowmeter as described in item 丨 of the patent application scope, wherein the 瀛 outlet is a type of tapered tube. > Lesser orders 5 · The jet flowmeter described in item 丨 of the patent application scope, wherein the multi-type micro-flow sensing element includes a plurality of micro-flow sensing elements. 6. The jet flowmeter as described in item 4 of the scope of the patent application, wherein the micro-flow sensing element that the fluid flows through the _th contact in the micro-flow channel is a heating element, and the remaining micro-flow sensing The element is a temperature sensing element. 7. The jet flow meter as described in item 4 of the scope of patent application, wherein the heating element is composed of polycrystalline silicon material. 88. The jet flowmeter as described in item 4 of the Shenjing patent scope, wherein the temperature-grinding sensing element is composed of polycrystalline silicon material. 9 · The jet flowmeter as described in item 1 of Shenjing's patent scope, in which the 誃 罝 妗 -type fluid vibration sensing element is composed of polycrystalline silicon material. 7