Detection device and cleaning method for blockage of DPF (diesel particulate filter)

Abstract

The invention discloses a detection device and a cleaning method for DPF blockage, and relates to the technical field of DPF blockage detection and cleaning, the device comprises a porous medium filtering wall surface which is mainly located on the inner wall of a particle trap, an infrared imager which is arranged in the porous medium filtering wall surface of the particle trap, an ultrasonic vibration device which is arranged outside the particle trap, and a detection device which is arranged on the inner wall of the particle trap. According to the device, the working condition of the particulate filter in a diesel engine is simulated by introducing fuel waste gas, the blockage condition of a porous medium filtering wall surface is detected in real time by adopting an infrared thermal imaging technology, and blocked particulate matters are removed by adopting an ultrasonic oscillation technology, so that the operation reliability of the particulate filter is guaranteed; and in addition, a vibration adjusting mode is set, so that the material of the particulate filter is not damaged while the blockage is cleaned.

Description

Technical Field

[0001] The invention relates to the technical field of DPF blockage detection and cleaning, and in particular to a DPF blockage detection device and cleaning method. Background Art

[0002] With the continuous upgrading of environmental protection regulations, the control of particulate matter (PM) in diesel engine exhaust emissions has become the focus of emission management. The particulate filter (DPF) is a key device that can intercept and capture soot and other particulate matter in diesel engine emissions. However, during the long-term use of the DPF, due to the continuous accumulation of particulate matter, the internal filter wall of the DPF will be blocked, thereby hindering the flow of exhaust gas, resulting in reduced emission performance and even adverse effects on engine operation. Common solutions such as high-temperature regeneration (burning particulate matter by increasing the exhaust temperature) can remove some particulate matter, but there are problems such as high energy consumption and strong dependence on operating conditions.

[0003] The blockage of the particulate filter is often not detected in real time until the blockage is serious enough to affect the engine performance. Therefore, there is an urgent need for a technical solution that can detect the blockage of the particulate filter in real time and clean the blockage in time to improve the reliability and work efficiency of the system operation.

[0004] In addition, since the material of the particulate collector is usually ceramic fiber or metal substrate, simply using the filter mesh clearing vibration program is likely to cause damage to the ceramic fiber or metal substrate. Summary of the invention

[0005] 1. Technical issues to be resolved In view of the shortcomings of the prior art, the present invention provides a DPF blockage detection device and cleaning method, which solves the following technical problems: 1. There is no detection system for DPF blockage in the prior art; 2. The vibration clearing method in the prior art can easily cause damage to the ceramic fiber or metal substrate in the particle collector.

[0006] (II) Technical solution To achieve the above objectives, the present invention is implemented through the following technical solutions: a detection device for a particle collector, the special feature of which is that the device comprises: Porous medium filter wall: set on the inner wall of the particle collector.

[0007] Soot layer: A dense layer formed by the gradual deposition of particulate matter (mainly soot and solid particles) in diesel engine exhaust, which covers the filter wall of the porous medium.

[0008] Infrared imager: used to detect the blockage of the filter wall inside the particle collector, and is installed on the inner wall of the particle collector.

[0009] Digital image computer: The infrared thermal image is transmitted to the digital image computer via wires for analysis.

[0010] Ultrasonic vibration device: arranged on the outer wall of the particle collector.

[0011] Filter membrane: installed in the exhaust duct.

[0012] A DPF blockage detection device comprises a plurality of infrared imagers and a digital image computer, wherein the infrared imager is used to obtain a thermal image of a porous medium filter wall surface of the DPF and transmit the thermal image to the digital image computer in real time; If there is a temperature difference between the thermal images obtained by multiple infrared imagers, it indicates that there is blockage on the porous medium filter wall; The degree of temperature difference between thermal images obtained by multiple infrared imagers indicates the degree of blockage of the porous medium filter wall.

[0013] Preferably, an ultrasonic vibration device is included, which is arranged outside the DPF and is used to generate high-frequency vibration to break up particulate matter blocked on the filter wall of the porous medium by mechanical vibration.

[0014] A method for cleaning a DPF blockage detection device comprises the following steps: S1: Infrared ray emitting devices and their corresponding receiving devices are deployed at multiple different collection points. The infrared ray intensity of each collection point is adjusted according to specific needs to ensure that the system can accurately detect the accumulation of particulate matter. Through this deployment, the particle distribution in the entire particle collector can be fully and carefully monitored; S2: After the diesel engine exhaust enters the system, the exhaust is first heated and burned at high temperature in the particle collector to initially decompose some of the larger particles and filter through the porous medium wall. Then, the infrared ray imager is started to image the exhaust after combustion; S3: The thermal image generated by the infrared imager is transmitted to the digital image computer through wires for real-time analysis. The digital image computer determines the abnormal area in the thermal image in combination with the engine operating power according to the set standards; If the engine operating power is less than 30% of the maximum continuous power designed by the engine, the time threshold for blocking infrared rays is set to 1.5A seconds; If the engine operating power is between 30% and 80% of the maximum continuous power designed for the engine, the time threshold for blocking infrared rays is set to A seconds; If the engine operating power is greater than 80% of the maximum continuous power designed for the engine, the time threshold for blocking infrared rays is set to 0.5A seconds; S4: If there is a temperature difference between the thermal images obtained by multiple infrared imagers, it indicates that there is blockage on the porous medium filter wall, and then the ultrasonic vibration device is started. The ultrasonic vibration device is a segmented vibration device. When a certain segment of the segmented vibration device is started, the porous medium filter wall at the corresponding position can be vibrated to clear the blockage. The ultrasonic vibration device starts low-intensity ultrasonic vibration to protect the ceramic fiber or metal substrate of the particle collector, and gradually increases the vibration intensity according to the preset logic until the infrared signal returns to normal; If the engine operating power is greater than 80% of the maximum continuous power designed for the engine, adopt global vibration to uniformly increase the overall vibration intensity in order to quickly clear the blocked particles; If the engine operating power is less than 30% of the maximum continuous power designed for the engine, local vibration should be adopted to directionally enhance the local vibration intensity, reduce the vibration frequency and intensity, and extend the monitoring and cleaning intervals to reduce equipment wear.

[0015] S5: During the decomposition process, small particles continue to be discharged through the exhaust channel and are filtered twice by the filter membrane in the channel. The filter membrane can capture the remaining small particles to ensure that the exhaust gas meets environmental protection requirements. At the same time, in order to prevent excessive vibration from damaging the ceramic fiber or other materials inside the DPF, the system strictly limits the vibration intensity; If the vibration intensity reaches the preset maximum value and still fails to remove the accumulated particles, the alarm device will be automatically triggered.

[0016] Preferably, A=10.

[0017] Preferably, the low-intensity ultrasonic vibration frequency is 20-30 kHz.

[0018] Preferably, the vibration intensity is gradually increased by 5-10 kHz each time.

[0019] Preferably, the preset maximum value of the vibration intensity is 50kH.

[0020] (III) Beneficial effects The present invention provides a DPF blockage detection device and cleaning method, which has the following beneficial effects: (1) The DPF blockage detection device and cleaning method use infrared detection and ultrasonic vibration technology to achieve real-time monitoring and efficient cleaning of the particle collector blockage, while protecting the equipment and reducing environmental pollution. (2) The DPF blockage detection device and cleaning method can achieve a clearing effect by adjusting the vibration while avoiding damage to the ceramic fiber or metal substrate in the particulate collector. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1It is a schematic diagram of the structure of the present invention.

[0022] In the figure: 1. Porous medium filter wall; 2. Soot layer; 3. Filter membrane; 4. Infrared imager; 5. Ultrasonic vibration device; 6. Digital image computer. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Porous media filter wall 1 The filter wall is located on the inner wall of the particulate filter and is usually made of high-porosity materials such as ceramics or metal fibers. The porous media wall is used to intercept particulate matter in diesel engine emissions, mainly soot and other particulate matter, and plays a physical filtering role. As particulate matter continues to accumulate, the soot layer on the filter wall gradually thickens, which may lead to flow restriction or even blockage.

[0025] Soot layer 2 The soot layer is composed of particulate matter (mainly soot and other solid particles) in diesel engine exhaust, which gradually deposits on the porous medium filter wall to form a dense soot layer. The thickening of the soot layer will affect the filtering performance of the particulate filter, and in severe cases may cause it to be completely blocked.

[0026] Infrared imager 4 The infrared imager is used to monitor the blockage of the porous medium filter wall in the particle collector. By emitting infrared rays and receiving the reflected thermal radiation, the imager can obtain a thermal image of the filter wall and transmit it to the digital image computer 6 for analysis in real time. Based on the temperature difference in the infrared image, the digital image computer can determine whether there is particle accumulation and evaluate the degree of blockage. If particles block the passage of infrared rays and the blocking time exceeds a preset threshold, it can be determined that the area is blocked.

[0027] Digital Image Computer 6 The digital image computer receives the thermal image transmitted by the infrared imager and analyzes it. The computer determines the blockage of the particle trap based on the analysis results of the infrared image. If blockage is found, the ultrasonic vibration device 5 is activated through the wire to clear the blockage.

[0028] Ultrasonic vibration device 5 The ultrasonic vibration device is used to generate high-frequency vibrations to break up the particles by mechanical vibration. The device is installed outside the particle collector and breaks the accumulated particles into smaller particles through vibration, reducing the severity of the blockage. The vibration intensity can be gradually increased according to the degree of blockage until it reaches the maximum value. If the vibration still does not clear the blockage, the system will trigger an alarm signal to prompt manual intervention.

[0029] Filter 3 The filter membrane is used in the exhaust channel to play a secondary filtering role. The smaller particles after vibration will pass through the exhaust channel and be collected by the filter membrane, thus preventing the uncleaned particles from further entering the exhaust system. The design of the filter membrane ensures that small particles will no longer cause system blockage and protect the subsequent exhaust system from contamination.

[0030] 1) Select three collection points and set an infrared ray device of a certain intensity and a corresponding receiving device at each collection point.

[0031] 2) The diesel engine exhaust is discharged into the device and then heated and burned once in the DPF (particulate filter) and the infrared ray imager is started 4 3) The infrared thermal image is transmitted to the digital image computer 6 through a wire for analysis. If particulate matter blocks the rays during their passage and the blocking time reaches a preset standard, it can be determined that the accumulation of particulate matter in the area may cause DPF blockage.

[0032] 4) The digital image computer 6 activates the ultrasonic vibration device 5 through the wire to break the large particles into smaller particles with gradually increasing vibration intensity until the ray receiving device resumes signal reception.

[0033] 5) Smaller particles are filtered through the exhaust channel and then filtered again through the filter membrane 3 in the channel. To avoid vibration damage to the ceramic fiber and other materials inside the DPF, the vibration intensity is controlled within a reasonable range. If the particle blockage cannot be cleared after reaching the preset maximum value, the alarm system is triggered to prompt manual intervention and remove the device for cleaning.

[0034] The specific implementation steps are as follows: 1. Infrared ray transmitters and their corresponding receiving devices are deployed at three different collection points. The infrared ray intensity of each collection point is adjusted according to specific needs to ensure that the system can accurately detect the accumulation of particulate matter. Through this arrangement, the particle distribution in the entire particulate filter (DPF) can be fully and carefully monitored.

[0035] 2. When the diesel engine exhaust enters the system, the exhaust is first heated and burned at high temperature in the particle collector to initially decompose some larger particles and filter them through the porous medium wall 1. Subsequently, the infrared ray imager 4 is started to image the exhaust after combustion. This method can clearly show the distribution and concentration of particulate matter in the area where the exhaust flows, providing key data support for subsequent analysis.

[0036] 3. The thermal image generated by the infrared imager 4 is transmitted to the digital image computer 6 through a wire for real-time analysis. The digital image computer 6 determines the abnormal area in the thermal image according to the set standards. The time threshold for blocking infrared rays is set to 10 seconds. The diesel exhaust gas flow rate is fast, and the accumulation of particles on the filter wall may quickly cause significant blockage. 10 seconds is a reasonable initial judgment time. At high loads (usually 80% to 100% of the maximum continuous power designed for the engine), it is shortened to 5 seconds to trigger cleaning more quickly. At low loads (the engine is in a state of no load, light load or short-term low-speed operation), it is extended to 15 seconds to reduce misjudgment.

[0037] 4. To solve the accumulation problem, the digital image computer 6 will send instructions to the ultrasonic vibration device 5 through the wire to start the cleaning program. The ultrasonic vibration device 5 gradually increases the vibration intensity and uses high-frequency vibration to break down larger particles into smaller particles. These smaller particles can pass through the DPF smoothly under the impetus of the exhaust flow, and the recovery of the infrared ray receiving device signal indicates that the particle blockage has been eliminated. The vibration device starts low-intensity ultrasonic vibration (20-30kHz) to protect the ceramic fiber or metal substrate of the particle collector. The vibration intensity is gradually increased according to the preset logic (increase by 5-10kHz each time) until the infrared signal returns to normal. At high loads, global vibration is adopted to uniformly increase the overall vibration intensity in order to quickly clean up the blocked particles; at low loads, local vibration is adopted to directionally enhance the local vibration intensity, reduce the vibration frequency and intensity, and extend the monitoring and cleaning interval to reduce equipment wear.

[0038] 5. During the decomposition process, small particles continue to be discharged through the exhaust channel and are filtered twice by the filter membrane 3 in the channel. The filter membrane 3 can capture the remaining small particles to ensure that the exhaust gas meets environmental protection requirements. At the same time, in order to prevent excessive vibration from damaging the ceramic fiber or other materials inside the DPF, the system strictly limits the vibration intensity. If the vibration intensity reaches the preset maximum value (50kHz) and still fails to remove the particle accumulation, the system will automatically trigger the alarm device. The alarm prompts the operator to manually intervene to disassemble and thoroughly clean the DPF to avoid more serious blockage problems.

[0039] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0040] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A DPF blockage detection device, comprising a plurality of infrared imagers (4) and a digital image computer (6), characterized in that: The infrared imager (4) is used to obtain a thermal image of the porous medium filter wall surface (1) of the DPF and transmit it to a digital image computer (6) in real time; If there is a temperature difference between the thermal images obtained by the multiple infrared imagers (4), it indicates that the porous medium filter wall (1) is blocked; The degree of temperature difference between the thermal images obtained by the multiple infrared imagers (4) indicates the degree of blockage of the porous medium filter wall (1).

2. A DPF clogging detection device according to claim 1, characterized in that: It comprises an ultrasonic vibration device (5), which is arranged outside the DPF and is used to generate high-frequency vibration to break up particles blocked on the porous medium filter wall (1) by means of mechanical vibration.

3. A method for cleaning a DPF blockage detection device according to claim 2, characterized in that: The steps include: S1: Infrared ray emitting devices and their corresponding receiving devices are deployed at multiple different collection points. The infrared ray intensity of each collection point is adjusted according to specific needs to ensure that the system can accurately detect the accumulation of particulate matter. Through this deployment, the particle distribution in the entire particle collector can be fully and carefully monitored; S2: After the diesel engine exhaust enters the system, the exhaust is first heated and burned at high temperature in the particle collector to initially decompose some of the larger particles and filter them through the porous medium wall (1). Subsequently, the infrared ray imager (4) is started to image the exhaust after combustion; S3: The thermal image generated by the infrared imager (4) is transmitted to the digital image computer (6) through a wire for real-time analysis. The digital image computer (6) determines the abnormal area in the thermal image in combination with the engine operating power according to a set standard; If the engine operating power is less than 30% of the maximum continuous power designed by the engine, the time threshold for blocking infrared rays is set to 1.5A seconds; If the engine operating power is between 30% and 80% of the maximum continuous power designed for the engine, the time threshold for blocking infrared rays is set to A seconds; If the engine operating power is greater than 80% of the maximum continuous power designed for the engine, the time threshold for blocking infrared rays is set to 0.5A seconds; S4: If there is a temperature difference between the thermal images obtained by the multiple infrared imagers (4), it indicates that the porous medium filter wall (1) is blocked, and the ultrasonic vibration device (5) is started. The ultrasonic vibration device (5) is a segmented vibration device. When a certain segment of the segmented vibration device is started, the porous medium filter wall (1) at the corresponding position can be vibrated to clear the blockage. The ultrasonic vibration device (5) starts low-intensity ultrasonic vibration to protect the ceramic fiber or metal substrate of the particle collector, and gradually increases the vibration intensity according to the preset logic until the infrared signal returns to normal; If the engine operating power is greater than 80% of the maximum continuous power designed for the engine, adopt global vibration to uniformly increase the overall vibration intensity in order to quickly clear the blocked particles; If the engine operating power is less than 30% of the maximum continuous power designed for the engine, local vibration should be adopted to directionally enhance the local vibration intensity, reduce the vibration frequency and intensity, and extend the monitoring and cleaning intervals to reduce equipment wear. S5: During the decomposition process, small particles continue to be discharged through the exhaust channel and are filtered twice by the filter membrane (3) in the channel. The filter membrane (3) can capture the remaining small particles to ensure that the exhaust gas meets environmental protection requirements. At the same time, in order to prevent excessive vibration from damaging the ceramic fiber or other materials inside the DPF, the system strictly limits the vibration intensity; If the vibration intensity reaches the preset maximum value and still fails to remove the accumulated particles, the alarm device will be automatically triggered.

4. The method for cleaning a DPF blockage detection device according to claim 3, characterized in that: Said A=10.

5. The method for cleaning a DPF blockage detection device according to claim 3, characterized in that: The low-intensity ultrasonic vibration frequency is 20-30 kHz.

6. The method for cleaning a DPF blockage detection device according to claim 3, characterized in that: The vibration intensity is gradually increased by 5-10kHz each time.

7. The method for cleaning a DPF blockage detection device according to claim 3, characterized in that: The preset maximum value of the vibration intensity is 50 kHz.

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