CN101876666A - Non-contact type acceleration measurement method and device of filter-bag - Google Patents

Abstract

The invention relates to non-contact type acceleration measurement method and device of a filter-bag. In the method, a laser displacement sensor 5 is arranged on a detection part of the filter-bag, and the distance between the laser displacement sensor 5 and the detection part of the filter-bag is controlled within the measuring range of the laser displacement sensor. The device comprises the laser displacement sensor 5, a sensor controller 7 and a data collector 8, wherein the sensor controller 7 is connected with the laser displacement sensor and the data collector, and the laser displacement sensor 5 is supported by a bracket 6. In the invention, an optical measurement device is adopted to carry out non-contact measurement on the filter-bag in a pulse clean-ash state, and a mathematical model is utilized to carry out effective treatment on a displacement curve to obtain an acceleration curve of the surface of the filter-bag, thereby avoiding the interference of a measurement device to the measured filter-bag, thus a measurement result has high reliability. The displacement condition of the filter-bag can be recorded while measuring the acceleration, and a speed change condition is obtained through carrying out first difference on the displacement.

Description

Contactless filter bag acceleration measurement method and device

Technical field

The present invention relates to a kind of measuring method and device of bag-type duster filtering bag acceleration, be specifically related to measuring method and device that sensor does not contact a kind of contactless filter bag acceleration of filter bag.

Background technology

Sack cleaner is as the important cleaner in industrial dedusting field, because the stability of its high-effective dust-removing and the reliability of qualified discharge, has been widely used in occasions such as metallurgy, cement, coloured, coal-burning boiler.The factor that influences the operational effect of sack cleaner has a lot, the deashing ability of wherein most important fly-ash separator, the deashing ability of fly-ash separator is estimated by the acceleration magnitude that filter bag obtains when pulse jet usually, and greatly then the deashing ability is strong for acceleration, a little less than the little then deashing of the acceleration ability.

In the experiment of research filter bag acceleration, extensively adopt miniature acceleration sensor to be pasted on the method on tested filter bag surface both at home and abroad at present, obtain the motion state that identical acceleration writes down filter bag simultaneously with filter bag by acceleration transducer.

And there is very big defective in this measuring method, because our the object filter bag of research is a textile, density is probably at 400 grams～800 gram/m ²Between, and nowadays minimum acceleration transducer nearly weighs 1g greatly, area is approximately 1cm ², and 1cm ²The filter bag quality be 0.04～0.08 the gram, less than 1/10 of acceleration transducer, therefore the acceleration transducer that sticks on the filter bag surface has had a strong impact on the motion of filter bag, and the acceleration of sensor measurement can not effectively reflect the motion state of filter bag, and research work is restricted.

Summary of the invention

The objective of the invention is to measure the defective that acceleration exists at the existing acceleration transducer that sticks on the filter bag surface, a kind of contactless filter bag acceleration measurement method and device are proposed, to detect real relatively accekeration, thereby correctly estimate the serviceability of soot cleaning system, provide technical support for improving cleaning efficiency.

The object of the invention realizes by following technical solution:

Contactless filter bag acceleration measurement device, constitute by laser displacement sensor, sensor controller and data acquisition unit, sensor controller connects laser displacement sensor and data acquisition unit, laser displacement sensor is installed in apart from filter bag according to range ability and detects position 6.5～9.5 centimeters, and laser displacement sensor is by stent support.

Contactless filter bag acceleration measurement method:

Throw beam of laser by the high-precision laser displacement transducer to the detection position on filter bag surface, the CCD imaging system of laser displacement sensor receives folded light beam simultaneously, determine the position on filter bag surface by the variation of receiving position, in case filter bag changes to swelling state by contraction state, laser displacement sensor just can be noted the micro-displacement on filter bag surface, and sampled data is transported to data acquisition unit by sensor controller, by the software processes of data acquisition unit, generate displacement curve.

Next handle by setting up the mathematical model displacement curve, obtain rate curve with the capable first difference of mathematical method contraposition shift-in, second order difference obtains accelerating curve, and concrete grammar is as follows:

With the time T is horizontal ordinate, is ordinate with displacement S, the diffusing point of the displacement that measures is coupled together obtain displacement curve f (1).(S (n+1)-Sn)/(T (n+1)-Tn) obtains the diffusing point of speed V, connects the point that looses and just obtains the rate curve f (2) of V about time T according to V=f ' (1)=dS/dT=Δ S/ Δ T ≈.(V (n+1)-Vn)/(T (n+1)-Tn) obtains the diffusing point of acceleration a, connects the point that looses and just obtains the accelerating curve f (3) of a about time T according to a=f ' (2)=dV/dT=Δ V/ Δ T ≈.At last accelerating curve is done multiple spot running mean smothing filtering, eliminate high frequency noise and disturb, can obtain revised acceleration a.

The invention has the beneficial effects as follows: the present invention adopts optical measuring device that filter bag has been carried out non-cpntact measurement under the pulse dust cleaning state, utilize mathematical model that displacement curve is effectively handled, obtain filter bag surface acceleration curve, avoided thus measuring the interference of components and parts to tested filter bag, measurement result is with a high credibility.The present invention can write down the displacement situation of filter bag when measuring acceleration, and by the displacement first difference is obtained the velocity variations situation.

Description of drawings

The contactless filter bag acceleration measurement device of Fig. 1

The displacement of Fig. 2 filter bag apparent motion and the curve map of time

The speed curve diagram that a differentiate of Fig. 3 Fig. 2 obtains

The acceleration plots that Fig. 4 Fig. 3 differentiate obtains

1. filter bag swelling states among the figure, 2. filter bag contraction state, 3. projection light, 4. reflected light, 5. laser displacement sensor, 6. support, 7. sensor controller, 8. data acquisition unit.

Embodiment

The present invention is described further below in conjunction with accompanying drawing:

Contactless filter bag acceleration measurement device is made up of laser displacement sensor 5, sensor controller 7 and data acquisition unit 8, and sensor controller 7 connects laser displacement sensor and data acquisition unit, and laser displacement sensor 5 is supported by support 6.

Contactless filter bag acceleration measurement method is installed laser displacement sensor 5 at the detection position of filter bag, and laser displacement sensor 5 detects the distance at position in the range ability of laser displacement sensor with filter bag.The detection method concrete steps are as follows:

A, laser displacement sensor 5 are to the detection position on filter bag surface projection beam of laser 3, and the CCD imaging system of laser displacement sensor 5 receives folded light beam 4 simultaneously;

B, change to swelling state 1 by contraction state 2 when filter bag, laser displacement sensor 5 gets off the displacement record on filter bag surface, and sampled data is transported to data acquisition unit 8 by sensor controller 7, by the software processes of data acquisition unit 8, generate displacement curve;

C, set up mathematical model and handle displacement curve, the capable first difference of contraposition shift-in obtains rate curve, and second order difference obtains accelerating curve.

Below be the situation of certain experiment measuring, measuring condition is:

(1) filter bag size φ 130 * 6000mm, the filter bag material is a canvas.

(2) the winding-up pipe is φ 112 * 2 welded tubes, and 20 of spray orifices, injection diameter are 21～28mm.

(3) jetting pressure is 0.3MPa.

(4) winding-up tube hub linear distance card 250mm, nozzle distance sack 140mm.

(5) pulse width is 40ms.

Flood valve when (6) the pulse valve model is plateau 3.

(7) gas bag useful volume ≈ 0.32m ³

(8) adopt laser feeler that the middle part of cloth bag is measured.

By pick-up unit, we have obtained the movement locus on filter bag surface, have set up the curve f (1) of displacement and time, as Fig. 2.

Obtain rate curve f (2) by a differentiate then, as Fig. 3.

Obtain accelerating curve f (3) by differentiate more at last, as Fig. 4.

Fig. 2, Fig. 3, Fig. 4 all are through multiple spot running mean smothing filtering, eliminate high frequency noise and disturb revised data.

Claims (4)

1. a contactless filter bag acceleration measurement method is characterized in that at the detection position of filter bag laser displacement sensor (5) being installed, and laser displacement sensor (5) detects the distance at position in the range ability of laser displacement sensor with filter bag.

2. contactless filter bag acceleration measurement device, it is characterized in that this device is made up of laser displacement sensor (5), sensor controller (7) and data acquisition unit (8), sensor controller (7) connects laser displacement sensor and data acquisition unit, and laser displacement sensor (5) is supported by support (6).

3. a kind of contactless filter bag acceleration measurement method as claimed in claim 1, its characterization step is:

A, laser displacement sensor (5) are to the detection position on filter bag surface projection beam of laser (3), and the CCD imaging system of laser displacement sensor (5) receives folded light beam (4) simultaneously;

B, change to swelling state (1) by contraction state (2) when filter bag, laser displacement sensor (5) gets off the displacement record on filter bag surface, and sampled data is transported to data acquisition unit (8) by sensor controller (7), by the software processes of data acquisition unit (8), generate displacement curve;

C, set up mathematical model and handle displacement curve, the capable first difference of contraposition shift-in obtains rate curve, and second order difference obtains accelerating curve.

4. a kind of contactless filter bag acceleration measurement method as claimed in claim 1, it is characterized in that: the range ability of laser displacement sensor (5) is 6.5～9.5 centimetres.

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