CN111562264A - Hand-held motor vehicle exhaust detection method - Google Patents

Abstract

The invention provides a hand-held motor vehicle tail gas detection method, which comprises the following steps: s1, emitting light rays into the channel receiving the tail gas through a laser emitting module of the laser; s2, reflecting the light after passing through the tail gas by a reflector which is arranged in the channel and is opposite to the laser emission module; s3, receiving the light reflected by the reflector through a laser reflection receiving module which is arranged opposite to the reflector and is opposite to the laser; s4, analyzing the signal received by the laser reflection receiving module through an analysis module; and S5, displaying the analysis result of the analysis module through a display. The method adopts the handheld motor vehicle tail gas detection device to detect the motor vehicle tail gas, and has the advantages of light carrying, convenience in use, simple detection process, high detection efficiency and the like.

Description

Hand-held motor vehicle exhaust detection method

Technical Field

The invention relates to the field of remote sensing monitoring of motor vehicle tail gas, in particular to a handheld motor vehicle tail gas detection method.

Background

With the continuous development of the automobile industry, the environmental problems brought by motor vehicles are increasingly prominent, the tail gas pollution of the motor vehicles becomes a main source of urban air quality hazard, the NOx and PM emitted by diesel trucks are obviously higher than those emitted by gasoline vehicles, the NOx emitted by the diesel vehicles in China is close to 70% of the total automobile emission amount, the PM exceeds 90%, especially the important cause of frequent haze occurrence in various cities in China in recent years is caused, and the supervision on the motor vehicles is increasingly strengthened. The current parking place supervision means mainly comprises road inspection spot check. The existing mode needs to carry a large number of instruments to go on the way, the equipment is heavy and has insufficient flexibility, and the detection and identification time is long.

The existing handheld detection equipment judges the Ringelman blackness value through video image identification, the identification method is to analyze and process by adopting a DSP intelligent algorithm according to the distribution characteristics of smoke plumes in a video image, judge whether a target emits black smoke or not according to a smoke plume characteristic video frame, screen out a picture with the maximum black smoke concentration in the video if the target emits the black smoke, and automatically analyze the Ringelman blackness grade corresponding to the black smoke concentration as a black smoke evidence picture.

The existing handheld detection equipment cannot detect the opacity value and cannot accurately judge an accurate result when the smoke plume of the tail gas of the motor vehicle does not form obvious black smoke.

Disclosure of Invention

In order to solve the technical problems, the invention provides a handheld motor vehicle exhaust detection method which has the advantages of simple detection process, high working efficiency and the like.

The handheld motor vehicle tail gas detection method provided by the embodiment of the invention comprises the following steps: s1, emitting light rays into the channel receiving the tail gas through a laser emitting module of the laser; s2, reflecting the light after passing through the tail gas by a reflector which is arranged in the channel and is opposite to the laser emission module; s3, receiving the light reflected by the reflector through a laser reflection receiving module which is arranged opposite to the reflector and is opposite to the laser; s4, analyzing the signal received by the laser reflection receiving module through an analysis module; and S5, displaying the analysis result of the analysis module through a display.

According to the handheld motor vehicle tail gas detection method, the laser transmission principle is utilized, required data can be obtained through analysis and processing of the analysis module, so that the accuracy and the detection working efficiency of motor vehicle tail gas detection data can be improved, and the method can be widely applied to motor vehicle road inspection, non-road mobile machinery detection and detection station black smoke detection.

According to one embodiment of the present invention, in step S4, the laser converts the light transmission signal into an electrical signal, and transmits the electrical signal to the analysis module through the communication cable.

According to one embodiment of the invention, the analysis module calculates the opacity value through the exhaust plume of the exhaust gas and outputs the opacity, the light absorption coefficient and the ringelman blackness grade data.

According to one embodiment of the invention, the display displays the opacity, light absorption coefficient and ringelman blackness grade data transmitted by the analysis module on a display screen.

According to an embodiment of the present invention, in step S4, the opacity value τ is calculated as shown in equation (1),

in the formula (1), phi₀The incident luminous flux is the light energy received by the laser reflection receiving module when the channel is full of air and does not have the tail gas; phi is transmitted luminous flux, and the transmitted luminous flux is the light energy received by the laser reflection receiving module when the channel is filled with the tail gas.

According to an embodiment of the present invention, the calculation formula of the opacity is shown as formula (2),

in the formula (2), N is the opacity.

According to an embodiment of the present invention, in step S4, the analysis module compares the opacity of the exhaust gas with a ringelman concentration map built in the analysis module, determines whether the exhaust gas is black smoke according to a comparison result, and outputs a ringelman blackness level.

According to one embodiment of the invention, when the opacity value is greater than or equal to the Ringelmann blackness by one level, black smoke is distinguished.

According to an embodiment of the present invention, the calculation formula of the light absorption coefficient K is shown in formula (3),

in the formula (3), L is an effective length of the laser back and forth reflection.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a flow chart of a method for detecting exhaust from a hand-held vehicle according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a handheld motor vehicle exhaust gas detection device according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a method for handheld vehicle exhaust detection in accordance with an embodiment of the present invention;

fig. 4 is a schematic diagram of a handheld vehicle exhaust detection method according to an embodiment of the invention.

Reference numerals:

a hand-held motor vehicleexhaust detection device 100;

alaser 10;

areflector 20; achannel 21;

ananalysis module 30;

adisplay 40;

acommunication cable 50.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "center", "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations or positional relationships based on those shown in the drawings, are only for convenience of description and simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The following describes a handheld motor vehicle exhaust detection method according to an embodiment of the present invention with reference to the accompanying drawings.

As shown in fig. 1 to 4, a handheld motor vehicle exhaust gas detection method according to an embodiment of the present invention includes the following steps:

s1, emitting light into thechannel 21 receiving the exhaust gas through the laser emitting module of thelaser 10.

And S2, reflecting the light after passing through the tail gas by thereflector 20 which is arranged in thechannel 21 and is opposite to the laser emission module.

S3, receiving the light reflected by thereflector 20 through a laser reflection receiving module disposed opposite to thereflector 20 and opposite to thelaser 10.

S4, theanalysis module 30 analyzes the signal received by the laser reflection receiving module.

S5, thedisplay 40 displays the analysis result of theanalysis module 30.

In other words, thelaser 10 has a laser emitting module and a laser receiving module, areflector 20 is disposed at one side of thelaser 10, thereflector 20 has a channel for receiving the exhaust gas, a mounting hole may be disposed at one side of the channel, a reflecting portion may be disposed at one side of the channel opposite to the mounting hole, thelaser 10 may be disposed at one side of thereflector 20, a laser emitting and receiving module of thelaser 10 is disposed at the mounting hole for receiving light reflected by the reflecting portion, one end of a supporting rod may be connected to thelaser 10, ananalyzing module 30 may be disposed at the other end of the supporting rod, and is connected to thelaser 10 through the analyzingmodule 30 for analyzing a signal received by thelaser 10, and adisplay 40 may be disposed at the analyzingmodule 30 for displaying an analysis result.

The exhaust gas black smoke of the motor vehicle consists of 80% of carbon black particles and about 20% of aerosol particles, the particles can absorb partial wave bands under visible light conditions, particularly green light wave bands in visible light are most sensitive, the exhaust gas pipe for removing the exhaust gas black smoke of the motor vehicle needs about 3S of diffusion time, and relevant signals can be captured in the diffusion time of the black smoke exhaust clusters, so that the exhaust gas black smoke emission condition of the vehicle can be judged. According to the handheld motor vehicle tail gas detection method, laser is adopted, the laser transmission principle is utilized, the opacity value tau is calculated through exhaust smoke plumes, the opacity N, the light absorption coefficient k and the Ringelmann blackness grade data are output, and the analysis response time of the detection method is in the millisecond level.

When tail gas detection is performed, tail gas is filled in a channel of areflector 20 of a support rod, laser is firstly emitted into achannel 21 which receives the tail gas through a laser emitting module, the laser can penetrate through thechannel 21 which is fully filled with the tail gas to reach thereflector 20, then the laser is reflected by thereflector 20 to reach a laser reflection receiving module of thelaser 10, that is, parallel light beams reflected by thereflector 20 are received by the laser reflection receiving module. According to the laser transmission principle, after laser passes through a specific gas (tail gas) environment, light energy is attenuated due to the absorption and scattering effects of gas and aerosol particles on light. Thelaser 10 can convert the light transmission signal into an electrical signal and transmit the electrical signal to theanalysis module 30 through the communication cable, and the magnitude of the electrical signal can be measured to indicate the magnitude of the light flux. The signals received by the laser reflection receiving module are analyzed by the analyzingmodule 30, and the analyzed results are finally displayed by thedisplay 40 after being analyzed and processed by the analyzingmodule 30.

Therefore, according to the handheld motor vehicle tail gas detection method disclosed by the embodiment of the invention, required data can be obtained by analyzing and processing theanalysis module 30 by utilizing the laser transmission principle, so that the accuracy and the detection working efficiency of motor vehicle tail gas detection data can be improved, and the detection method can be widely applied to motor vehicle road inspection, non-road mobile machinery detection and detection station black smoke detection.

According to one embodiment of the present invention, in step S4, thelaser 10 converts the light transmission signal into an electrical signal and transmits the electrical signal to theanalysis module 30 through thecommunication cable 50, and the magnitude of the electrical signal is measured to indicate the magnitude of the light flux.

Optionally, theanalysis module 30 calculates an opacity value from the exhaust plume of the exhaust gas and outputs opacity, light absorption coefficient, and ringelman blackness level data. Theanalysis module 30 may obtain data to be detected by a preset calculation method, so as to achieve the purpose of detection.

Preferably, thedisplay 40 displays the opacity, light absorption coefficient and ringelman blackness scale data transmitted by theanalysis module 30 on a display screen. Thedisplay 40 may be provided with an OLED display screen, and when theanalysis module 40 transmits the analysis result to thedisplay 40, the display screen may clearly display the required data, so that the inspector can directly observe and record the relevant data value.

In some embodiments of the present invention, in step S4, the opacity value τ is calculated as shown in formula (1),

in the formula (1), τ is an opacity value, [ phi ]₀The incident luminous flux is the light energy received by the laser reflection receiving module when the channel is full of air without tail gas, and the air is the air without tail gas in a normal state; phi is the transmitted luminous flux which is the light energy received by the laser reflection receiving module when the channel is filled with tail gas. The magnitude of the luminous flux is represented by the magnitude of the measured electric signal, where₀Is the mean value without tail gas, and phi is a variable, and needs to pass through each realThe actual measurement is obtained.

According to an embodiment of the present invention, the calculation formula of the opacity N is shown in formula (2),

in the formula (2), N is the opacity, and is calculated by the result tau of the formula (1) or directly by phi₀And phi is calculated to obtain the opacity N.

Alternatively, in step S4, theanalysis module 30 compares the opacity N of the exhaust gas with the ringelman concentration map built in theanalysis module 30, determines whether the smoke is black smoke according to the comparison result, and outputs a ringelman blackness level. The lingeman concentration graph is generally composed of six graph boards with different blackness of 14 cm x 21 cm, and other four graph boards except for a full black graph board and a full white graph board are black bars with different widths, wherein the larger the lingeman blackness grade is, the larger the percentage of the black bars is. By comparing the opacity with the percentage of black boxes, the lingemann blackness rating can be determined.

In some embodiments of the present invention, black smoke is discriminated when the opacity value τ is equal to or greater than ringer-Mannheim by one step. That is to say, when the lingemann blackness is one level, the black bars account for 20% of the whole area, so when the opacity is greater than 20%, the exhaust to be detected can be judged to be black smoke.

According to an embodiment of the present invention, the calculation formula of the light absorption coefficient K is shown in formula (3),

in the formula (3), K is the light absorption coefficient, and L is the effective length of the laser back and forth reflection. That is, theanalysis module 30 may calculate the light absorption coefficient K of the exhaust gas through Beer-Lambert's law.

In summary, according to the handheld automobile exhaust gas detection method of the embodiment of the present invention, by using the principle of laser transmission, laser light passes through the exhaust gas environment in the channel to reach thereflector 20, and is received by the laser reflection receiving module of thelaser 10 after passing through thereflector 20. Thelaser 10 converts the received light-transmissive signal into an electrical signal and transmits it to theanalysis module 30 via thecommunication cable 50. Theanalysis module 30 can calculate and analyze the received signals and transmit the analysis result to thedisplay 40 for displaying, and the detection method has the advantages of simple and rapid detection process, high accuracy and work efficiency of the detected data, and the like.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is a preferred embodiment of the present invention, and it should be noted that it would be apparent to those skilled in the art that various modifications and enhancements can be made without departing from the principles of the invention, and such modifications and enhancements are also considered to be within the scope of the invention.

Claims (9)

1. A hand-held motor vehicle exhaust detection method is characterized by comprising the following steps:

s1, emitting light rays into the channel receiving the tail gas through a laser emitting module of the laser;

s2, reflecting the light after passing through the tail gas by a reflector which is arranged in the channel and is opposite to the laser emission module;

s3, receiving the light reflected by the reflector through a laser reflection receiving module which is arranged opposite to the reflector and is opposite to the laser;

s4, analyzing the signal received by the laser reflection receiving module through an analysis module;

and S5, displaying the analysis result of the analysis module through a display.

2. The method for detecting exhaust gas of a hand-held vehicle according to claim 1, wherein in step S4, the laser converts the light transmission signal into an electrical signal, and transmits the electrical signal to the analysis module through a communication cable.

3. The method of claim 1, wherein the analysis module calculates an opacity value from the exhaust plume of the exhaust and outputs opacity, light absorption coefficient, and ringelman blackness rating data.

4. The hand-held motor vehicle exhaust detection method of claim 3 wherein the display displays the opacity, light absorption coefficient and ringelman darkness grade data transmitted by the analysis module on a display screen.

5. The method for detecting exhaust gas of handheld motor vehicle according to claim 3, wherein in step S4, the opacity τ is calculated as shown in formula (1),

in the formula (1), phi₀The incident luminous flux is the light energy received by the laser reflection receiving module when the channel is full of air and does not have the tail gas; phi is transmitted luminous flux, and the transmitted luminous flux is the light energy received by the laser reflection receiving module when the channel is filled with the tail gas.

6. The hand-held vehicle exhaust gas detection method according to claim 5, wherein the opacity is calculated as shown in equation (2),

in the formula (2), N is the opacity.

7. The method for detecting tail gas of handheld motor vehicle of claim 6, wherein in step S4, the analysis module compares the opacity of the tail gas with a ringer Mannheim concentration chart built in the analysis module, determines whether the smoke is black smoke according to the comparison result, and outputs a ringer Mannheim level.

8. The hand-held automotive exhaust detection method of claim 7 wherein black smoke is identified when the opacity value is greater than or equal to the ringelmann blackness by one step.

9. The hand-held motor vehicle exhaust gas detection method according to claim 6, wherein the calculation formula of the light absorption coefficient K is shown in formula (3),

in the formula (3), L is an effective length of the laser back and forth reflection.

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