CN205720294U - Flow velocity automatic measurement mechanism - Google Patents

Abstract

The utility model discloses an automatic measurement device for flow velocity. The device comprises a release tube, a common probe and an agent hopper. The front end of the agent hopper is connected with the release tube. Equipped with a public probe and a detection probe, the common probe is connected to the low level of the controller signal, and the detection probe is connected to the high level of the controller signal. The flow velocity measuring device of the utility model obtains the movement time of the water flow by monitoring the change of the electrical conductivity between the common probe and the detection probe, and then calculates the flow velocity of the water flow. High-concentration ionization reagent causes the conductivity between the detection probe and the public probe to change, and the time spent by the ionization reagent at a certain distance is obtained, so as to calculate the movement speed of the ionization reagent, that is, the corresponding water flow rate, with high measurement accuracy and good stability, etc. advantage.

Description

Flow velocity automatic measurement mechanism

Technical field

This utility model relates to flow velocity automatic measurement mechanism, belongs to flow-speed measurement field.

Background technology

Flow velocity is the basic parameter describing water flow motion character istics, and under lab, it is must to survey parameter during modelling verification, working condition tests or scheme comparison etc..Flow-speed measurement method is often had to have Pitot tube, miniature propeller type current meter, ultrasound wave Doppler current meter (ADV), hot line hot film current meter (HWFA), laser dopper flowmeter current meter (LDV/LDA), particle image velocimeter (PIV) and surface flow field image velocimetry (RMSIV) etc..Owing to the instrumentations such as ADV, HWFA, LDV/LDA, PIV, RMSIV are complicated, expensive, it is difficult to large-scale application；Still further aspect, Pitot tube automaticity is low, and miniature propeller type current meter is easily disturbed by water quality, and certainty of measurement is limited, therefore, in the urgent need to taking into account the flow velocity new method of certainty of measurement and operability simultaneously.

Utility model content

Utility model purpose: in order to overcome the deficiencies in the prior art, this utility model provides a kind of flow velocity automatic measurement mechanism, indirectly measures flow rate of water flow by measuring the change of electrical conductivity between common probe and detection probe, and plant automation degree is high.

Technical scheme: for solving above-mentioned technical problem, a kind of flow velocity automatic measurement mechanism of the present utility model, including release pipe, common probe mediating recipe feed bin, described dose of feed bin front end connects with release pipe, it is provided with electromagnetic switch bottom release pipe, agent feed bin rear end is equipped with common probe and detection probe, and common probe is connected with controller signals low level, and detection probe is connected with controller signals high level.

As preferably, described release pipe is hollow structure, and external diameter 3-5mm, internal diameter 1-2mm communicate with agent feed bin, and agent feed bin top sets injecting hole.

As preferably, described detection probe is n, and n is the even number more than 1, and common probe is positioned at same straight line with detection probe core, n detection probe is arranged symmetrically with along release pipe with the common probe line of centres, and adjacent detection probe separation or detection probe and common probe interval are the most equal.

As preferably, described common probe and all detection probe materials are rustless steel, external diameter 1-3mm.

As preferably, upstream, water movement direction arranged by described release pipe, and common probe is arranged in downstream, water movement direction, and the distance between common probe and release pipe is that L, L discharge pipe external diameter equal to 2-3 times, and wherein L is no less than 6mm；Common probe and detection probe length are equal, than release pipe range L.

As preferably, the value of described n is 2,2 detection probes are respectively left detection probe and right detection probe, controller controls left detection probe and right detection probe does not simultaneously turns on, to prevent because water quality causes the electric current motion that cause different with right detection probe current potential of left detection probe, the monitoring of electrical conductivity between impact detection probe and common probe.

As preferably, described n value is the even number more than 2, and detection probe is Δ t with common probe ON time:

Δt<L/V_max/n/2

Vmax is current Peak Flow Rate to be measured；

Detection probe numbering, odd number is positioned on the left of common probe and by increasing numbering the most successively, even number is on the right side of common probe and by increasing numbering the most successively, from the odd number detection probe that distance common probe is nearest, sequentially turns on detection probe and common probe.

Beneficial effect: flow velocity automatic measurement mechanism of the present utility model, the time of flow is gone out by measuring the measure of the change of electrical conductivity between common probe and detection probe, and then measure flow rate of water flow, measurement process is all automatically performed by controller, plant automation degree is high, and this apparatus structure is ingenious, low cost；The measuring method of flow velocity automatic measurement mechanism of the present utility model, utilize high concentration ionization reagents from release pipe release, high concentration ionization reagents causes conductivity variations between detection probe and common probe, thus measure the time that ionization reagents is used on certain distance, measuring the flow velocity of ionization reagents, certainty of measurement is high.

Accompanying drawing explanation

Fig. 1 is main TV structure schematic diagram of the present utility model.

Fig. 2 is release pipe of the present utility model, common probe and the position view of detection probe.

Fig. 3 is test structural representation of the present utility model.

Detailed description of the invention

As shown in Figure 1 to Figure 3, a kind of flow velocity automatic measurement mechanism of the present utility model, including release pipe 1, common probe 2 mediating recipe feed bin 5, described dose of feed bin 5 front end connects with release pipe 1, it is provided with electromagnetic switch bottom release pipe 1, agent feed bin 5 rear end is provided with common probe 2 and detection probe 3, and common probe 2 is connected with controller 6 signal low level, and detection probe 3 is connected with controller signals high level.

In this utility model, described release pipe 1 is hollow structure, and external diameter 3-5mm, internal diameter 1-2mm communicate with agent feed bin 5, and agent feed bin 5 top sets injecting hole.Described detection probe has 5, and common probe 2 and 6 detection probes are located along the same line, and 6 detection probes are arranged symmetrically with along release pipe 1 with common probe 2 line of centres, and adjacent detection probe 3 is spaced or detects probe 3 and common probe 2 is spaced the most equal.

In this utility model, described common probe 2, detection probe material are rustless steel, external diameter 1-3mm, upstream, water movement direction arranged by described release pipe, common probe 2 is arranged in downstream, water movement direction, described common probe 2 discharges pipe 1 external diameter apart from for L, L equal to 2-3 times with release pipe 1, and wherein L is no less than 6mm；Common probe 2 and all of detection probe length are equal, than the release long L of pipe 1.

In this utility model, the value of described n is 2,2 detection probes are respectively left detection probe and right detection probe, controller controls left detection probe and right detection probe does not simultaneously turns on, to prevent because water quality causes the electric current motion that cause different with right detection probe current potential of left detection probe, the monitoring of electrical conductivity between impact detection probe and common probe.

In this utility model, described n value can also be the even number more than 2, and detection probe is Δ t with common probe ON time:

Δt<L/V_max/n/2

Vmax is current Peak Flow Rate to be measured；

Detection probe numbering, odd number is positioned on the left of common probe, and even number is on the right side of common probe, from the odd number detection probe that distance common probe is nearest, sequentially turns on detection probe and common probe.Such as from high order end number consecutively 1,3,5,2,4,6, from No. five detection probe conducting, then according to 2,4,6,1,3,5 circulations sequentially turn on detection probe and common probe.

The measuring method of a kind of above-mentioned flow velocity automatic measurement mechanism, comprises the following steps:

1) release pipe 1,2,6 detection probes of common probe being placed in flow position to be measured, release pipe 1 is in common probe 2 upstream, and agent feed bin 5 is higher than the water surface, in order to reagent flows out under gravity automatically from release pipe 1；

2) configuration high concentration ionization reagents (such as saline), concentration is not less than 50%, and injectant feed bin 5；

3) controller 6 control release pipe 1 lower end electromagnetic valve is opened, and flows out ionization reagents, is automatically switched off after 0.5 second, records electromagnetic valve opening time T₀；

4) controller 6 detects 6 detection probes electrical conductivity respectively and between common probe 2, initial conductivity G between detection probe and common probe 2₁、G₂、G₃、G₄、G₅、G₆, detection probe is uniformly distributed with common probe, adjacent between distance be Δ L, when ionization reagents flows through and detects between probe and common probe 2, when ionization reagents flows through numbered 5th detection probe, electrical conductivity G₃To change, the record corresponding time is T₁；Distance L between detection probe and release pipe 1_m；

5) then discharge the flow velocity between pipe 1 and common probe 2 and direction be:

$\begin{array}{cc}V=\sqrt{L_m^2+L^2}/(T_1-T_0)& \mathrm{\&alpha;}=\arctan (L_m/L)\end{array}.$

The above is only preferred implementation of the present utility model; it is noted that, for those skilled in the art; on the premise of without departing from this utility model principle, it is also possible to make some improvements and modifications, these improvements and modifications also should be regarded as protection domain of the present utility model.

Claims (7)

1. The flow rate automatic measuring device is characterized in that: it includes a release tube, a public probe and a drug hopper, the front end of the agent hopper is connected to the release tube, an electromagnetic switch is provided at the bottom of the release tube, and a public probe is installed at the rear end of the agent hopper. The probe and the detection probe, the common probe is connected with the low level of the controller signal, and the detection probe is connected with the high level of the controller signal. 2. The flow rate automatic measuring device according to claim 1, characterized in that: the release pipe is a hollow structure with an outer diameter of 3-5 mm and an inner diameter of 1-2 mm, which communicates with the agent silo, and the top of the agent silo is provided with an injection agent hole. 3. The flow velocity automatic measuring device according to claim 1, characterized in that: there are n detection probes, n is an even number greater than 1, the center of the common probe and the detection probe is located on the same straight line, and n detection probes The probes are arranged symmetrically along the line connecting the center of the release tube and the common probe, and the interval between adjacent detection probes or between the detection probe and the common probe is equal. 4. The flow velocity automatic measuring device according to claim 3, characterized in that: the common probe and all detection probes are made of stainless steel with an outer diameter of 1-3 mm. 5. The flow rate automatic measuring device according to claim 3 or 4, characterized in that: the release pipe is arranged upstream in the direction of water flow movement, the common probe is arranged downstream in the direction of water flow movement, and the distance between the common probe and the release pipe is L is equal to 2-3 times the outer diameter of the release tube, where L is not less than 6mm; the length of the public probe and the detection probe are equal, and L is longer than the release tube. 6. The flow velocity automatic measuring device according to claim 3, characterized in that: the value of said n is 2, and the two detection probes are respectively a left detection probe and a right detection probe, and the controller controls the left detection probe The needle and the right detection probe are not turned on at the same time. 7. The flow rate automatic measuring device according to claim 3, characterized in that: the value of n is an even number greater than 2, and the conduction time between the detection probe and the common probe is Δt: Δt<L/V _max /n/2 Vmax is the maximum velocity of water to be measured; Detection probe number, the odd number is located on the left side of the public probe and the number increases from left to right, the even number is on the right side of the public probe and the number increases from left to right, starting from the nearest public probe Beginning with odd-numbered detection probes, the detection probes and common probes are turned on in sequence.