CN210441918U - Gas-solid two-phase flow parameter detection device - Google Patents

Abstract

The present disclosure relates to a gas-solid two-phase flow parameter detection device, comprising: the detection probe is arranged on the cross section of the pipeline to be detected in a surrounding mode and comprises an invasive acoustic emission device and a powder flow velocity measuring device; and the multi-channel signal processing circuit board is electrically connected with the detection probe and comprises a signal conditioning circuit and a microcontroller. The method makes up the defects of a single acoustic emission sensor, realizes the online detection of the concentration and the mass flow of the gas-solid two-phase flow, and can display the measurement results of the flow velocity, the concentration, the mass flow and the fineness of the gas-solid two-phase flow in real time.

Description

Gas-solid two-phase flow parameter detection device

Technical Field

The utility model relates to a gas-solid two-phase flow on-line measuring device, and more specifically relates to a fuse online parameter detection device of gas-solid two-phase flow of acoustic emission and powder speed measurement technique.

Background

With the development of industry, pneumatic transmission pipelines are widely used in industrial fields of electric power, metallurgy, chemical industry, food and the like. The online detection of the gas-solid two-phase flow parameters is beneficial to improving the production efficiency, ensuring the safe and stable operation of the pneumatic conveying pipeline and reducing the emission of pollutants. However, the gas-solid two-phase flow has the phenomena of uneven powder distribution, irregular velocity profile, inconsistent powder particle size and shape, interference of moisture components, powder deposition on the pipe wall and the like in the pipeline, the flow characteristic is extremely complex, and the accurate measurement of the flow parameter is very difficult. Through the development of many years, scholars at home and abroad propose gas-solid two-phase flow parameter measurement methods based on different principles and technologies, including contact detection technologies such as a constant-speed sampling method and a thermal equilibrium method, and non-contact measurement technologies such as an optical method, a digital imaging method, a process tomography method, an acoustic method, a microwave method and an electrostatic method. The existing detection technology is difficult to carry out industrial on-line measurement due to respective limitations such as strong invasiveness, complex system, high price and the like. In 2001, the british department of trade and industry indicated in the technical report of "method for measuring and controlling flow of pulverized coal in utility boiler": the most promising approaches (i.e. approaches that can reach the application state) are electrostatic, microwave and acoustic techniques. The intrusive type acoustic method allows powder particles to collide with an intrusive waveguide rod to generate an acoustic emission signal, and is little affected by the environment and high in anti-interference capability. However, the acoustic emission signal contains a large amount of powder flow information, such as powder fineness, speed, concentration and the like, and a single flow parameter cannot be effectively represented.

Novel content

The utility model aims at providing a gas-solid two-phase flow parameter detection device, include: the detection probe is arranged on the cross section of the pipeline to be detected in a surrounding mode and comprises an invasive acoustic emission device and a powder flow velocity measuring device; and the multi-channel signal processing circuit board is electrically connected with the detection probe and comprises a signal conditioning circuit and a microcontroller.

Preferably, the invasive acoustic emission device comprises an acoustic emission wave guide rod and an acoustic emission sensor, wherein the front end of the acoustic emission wave guide rod invades into the fluid of the pipeline to be detected, and the acoustic emission sensor is arranged at the tail end of the acoustic emission wave guide rod.

Preferably, the powder flow velocity measuring device is disposed adjacent to the acoustic emission waveguide rod and at an upstream position thereof.

Preferably, the acoustic emission waveguide rod is made of a wear-resistant ceramic material.

Preferably, the number of the detection probes is at least one.

Compared with the prior art, the gas-solid two-phase flow online parameter detection device has the advantages that the gas-solid two-phase flow online parameter detection device integrating the acoustic emission and powder velocity measurement technologies is adopted, the defect of a single acoustic emission sensor is overcome, the online detection of the concentration and the mass flow of the gas-solid two-phase flow is realized, and the measurement results of the flow velocity, the concentration, the mass flow and the fineness of the gas-solid two-phase flow can be displayed in real time. Can provide a brand new detection device for scientific research of gas-solid two-phase flow characteristics and on-line continuous measurement of powder flow parameters in industrial fields.

Drawings

FIG. 1 is a schematic diagram of the principle structure of an online parameter detection device for gas-solid two-phase flow

Fig. 2 is a schematic structural diagram of a detection probe.

The reference numerals are specifically: 1. a gas-solid two-phase flow pipeline; 2. detecting a probe; 3. powder particles; 4. an invasive acoustic emission device; 5. a powder flow velocity measuring device; 6 multi-channel signal processing circuit board; 7. a signal conditioning circuit; 8. a microcontroller; 9. embedded systems such as data converters, transmitters, or industrial computers; 10. an acoustic emission waveguide; 11. an acoustic emission sensor.

Detailed Description

To make the objects, technical solutions and advantages of the present novel embodiments clearer, the technical solutions in the present novel embodiments will be clearly and completely described below with reference to the accompanying drawings in the present novel embodiments.

FIG. 1 is a schematic diagram of the principle structure of an online parameter detection device for gas-solid two-phase flow. In the figure, a detection probe 2 consists of an invasive acoustic emission device 4 and a powder flow velocity measuring device 5, the cross section of the pipeline is installed in a surrounding manner, and one, two, three, four or more (three detection probes 2 are installed on a gas-solid two-phase flow pipeline 1) can be installed according to the field requirement and used for acquiring the powder flow velocity and concentration information of the whole pipeline cross section; the intrusive type acoustic emission device 4 comprises an acoustic emission wave guide rod and an acoustic emission sensor, is inserted into the gas-solid two-phase flow pipeline 1, and powder particles 3 collide with the intrusive type wave guide rod to generate an acoustic emission signal which is detected by the acoustic emission sensor; the powder flow velocity measuring device 5 can be constructed by using a currently known reliable powder velocity measuring method, such as an electrostatic method, a capacitance method, an optical method, an ultrasonic method, a microwave method, a nuclear radiation method and the like; the acoustic emission signals detected by the plurality of detection probes 2 and the signals obtained by the powder speed measuring device are transmitted to the multi-channel signal processing circuit board 6; the signal conditioning circuit 7 is provided with an adjustable amplification gain and a band-pass filter, and can condition the weak signal into a voltage signal with proper voltage amplitude and bandwidth; the microcontroller 8 synchronously acquires a plurality of paths of signals and processes the signals in real time by using a double-precision floating point arithmetic unit and a digital signal processing instruction; the multi-channel signal processing circuit board 6 transmits the obtained signal characteristics to embedded systems such as a data converter and a transmitter or an industrial computer 9 through an interface; more accurate powder flow velocity, concentration, mass flow and fineness measurement results are obtained on embedded systems such as a data converter and a transmitter or an industrial computer 9 through a data fusion algorithm and are displayed on an embedded system or an upper computer interface in real time.

Fig. 2 is a schematic diagram of the principle structure of the detection probe. The powder flow velocity measuring device 5 is an auxiliary device of an acoustic emission device, mainly provides powder velocity information for acoustic emission signal analysis, is close to the acoustic emission wave guide rod 10 and is arranged at the upstream position of the acoustic emission wave guide rod; the front end of the acoustic emission wave guide rod 10 invades into fluid, the tail end is provided with an acoustic emission sensor 11, and the middle part is fixed by silica gel to prevent the interference of pipeline vibration and external collision on acoustic emission signals of gas-solid two-phase flow; the acoustic emission waveguide rod 10 can adjust the depth of invasion of fluid according to the field requirement, and can reduce the interference of the fluid and prevent the excessive aliasing of the signals of particle collision; the acoustic emission waveguide rod 10 is made of wear-resistant ceramic materials, so that impact abrasion of powder particles to the waveguide rod is reduced; the acoustic emission sensor 11 is made of piezoelectric ceramics, and has the advantages of small volume, high resolution, fast response and the like.

This novel acoustic emission signal based on 2 outputs of test probe and the gained signal of powder speed measuring device carry out the parameter detection of gas-solid two-phase flow, specifically do: determining the concentration and mass flow of the powder according to the acoustic emission signal and the powder flow velocity information; identifying the peak voltage in the acoustic emission signal, determining the powder fineness according to the peak voltage and the powder flow rate information, and determining the powder concentration and mass flow according to the powder fineness information of the pipeline section flowing in unit time, the powder flow rate information and the powder particle density. The two methods are respectively adopted for measuring a plurality of devices on the section of the pipeline, particle flow information of a plurality of local areas in the pipeline can be obtained, data fusion is carried out on the local information, the precision of powder flow velocity, concentration, mass flow and fineness measurement can be improved, and the measurement result is displayed in real time.

It is obvious to a person skilled in the art that the present invention is not restricted to details of the above-described exemplary embodiments, but that it can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Claims (6)

1. A gas-solid two-phase flow parameter detection device is characterized in that:

the detection probe is arranged on the cross section of the pipeline to be detected in a surrounding mode and comprises an invasive acoustic emission device and a powder flow velocity measuring device;

and the multi-channel signal processing circuit board is electrically connected with the detection probe and comprises a signal conditioning circuit and a microcontroller.

2. The apparatus according to claim 1, wherein the invasive acoustic emission device comprises an acoustic emission waveguide having a front end penetrating into the fluid in the pipe to be tested and an acoustic emission sensor having a distal end mounted thereon.

3. The detection apparatus of claim 2, wherein the powder flow rate measurement device is positioned proximate to and upstream of the acoustic emission waveguide.

4. The sensing apparatus of claim 2, wherein the acoustic emission waveguide is formed from a wear resistant ceramic material.

5. The inspection device of claim 2, wherein the acoustic emission sensor is made of a piezoelectric ceramic.

6. A testing device according to claim 1 wherein the number of test probes is at least one.

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