An oil fume generating device and a method for detecting oil fume capturing capacity of an extractor hood

Abstract

This invention provides an oil fume generating device and a method for testing the oil fume collection ability of a range hood. It provides a standard oil fume source to simulate the dynamic oil fume flow field of real cooking, enabling accurate comparison of test results. The oil fume collection ability of the range hood is comprehensively evaluated by the total amount of oil fume escape, the oil fume escape time ratio, the oil fume escape area ratio, and the intensity of curve fluctuation, thereby improving the accuracy of testing the oil fume collection ability of the range hood.

Description

Technical Field

[0001] This invention relates to the field of kitchen appliance technology, and in particular to an oil fume generating device and a method for testing the oil fume collection capacity of a range hood. Background Technology

[0002] The core performance indicator of a range hood is its ability to capture and isolate cooking fumes. Currently, this performance indicator is generally assessed by using a concentration comparison method based on contact sensors (such as particulate matter sensors).

[0003] This method requires the fume generator to output stable fume particles. However, current fume generators are non-standardized, and the rate, concentration, particle size, and temperature of fume generation are uncontrollable and cannot be repeated. This results in large dispersion of the test structure, making accurate comparison impossible. At the same time, the detection results of contact sensors are only local concentration values ​​with low accuracy. Contact sensors can also interfere with the flow field and change the direction of fume airflow, failing to reflect the complex diffusion and escape of fumes during the suction and exhaust process, and thus failing to accurately detect the fume collection capacity of the range hood. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide an oil fume generating device and a method for testing the oil fume collection capacity of a range hood, providing a standard oil fume source to simulate the dynamic oil fume flow field of real cooking; enabling accurate comparison of test results; and comprehensively evaluating the oil fume collection capacity of the range hood by the total amount of oil fume escape, the oil fume escape time ratio, the oil fume escape area ratio, and the intensity of curve fluctuation, thereby improving the accuracy of testing the oil fume collection capacity of the range hood.

[0005] To solve the above-mentioned technical problems, the technical solution used in this invention is as follows:

[0006] The present invention provides an oil fume generating device, comprising an aerosol generating system, a flow field and temperature field generating system, and an exhaust pipe; the aerosol generating system is connected to the input end of the exhaust pipe, the aerosol generating system is used to generate oil fume particles and control the amount of oil fume particles generated, the aerosol generating system is also used to mix oil fume particles with air to form oil fume aerosol, and control the amount of air mixed to adjust the total amount of oil fume aerosol;

[0007] The flow field and temperature field generation system includes a temperature field component and a porous flow field component. The output end of the exhaust duct is connected to the porous flow field component, and the temperature field component is fitted outside the exhaust duct. The end of the temperature field component near the porous flow field component has an output port. The temperature field component generates heated airflow and controls the amount of air and heat of the heated airflow. The heated airflow is discharged from the output port. The oil fume aerosol is heated by the temperature field component and discharged through the porous flow field component to form an oil fume jet plume.

[0008] Preferably, the temperature field component includes a second fan, a heating tube, and a honeycomb rectifier. The honeycomb rectifier is sleeved outside the exhaust duct, the second fan is connected to the heating tube, and the heating tube is connected to the honeycomb rectifier.

[0009] Preferably, the output port is arranged in a ring shape.

[0010] Preferably, the aerosol generating system includes an oil fume sprayer and a first fan, both of which are connected to the input end of the exhaust duct.

[0011] This invention also provides a method for detecting the oil fume collection capacity of a range hood, including an oil fume generating device, characterized by comprising the following steps:

[0012] S1. Pre-installed fume generator and range hood; pre-set fume collection interface; pre-installed laser and camera device, with the camera device lens equipped with a filter group.

[0013] S2. Start the fume generator, range hood, and laser.

[0014] S3. The laser illuminates the smoke collection interface, and the camera device collects a sequence of scattered laser images of the oil fume aerosol concentration field.

[0015] S4. Preset a quantitative relationship model between image thickness and oil fume mass concentration; convert the scattered laser image sequence of oil fume aerosol concentration field into a grayscale image to obtain the image grayscale information of oil fume concentration in each frame of grayscale image. The image grayscale information of oil fume concentration includes the average grayscale value of oil fume mass concentration and the ratio of oil fume escape area to the area of ​​the smoke collection interface.

[0016] S5. Establish curves showing the changes in average oil fume concentration, oil fume escape area, and total oil fume mass over time, and extract information on the ratio of total oil fume escape, ratio of oil fume escape area, ratio of oil fume escape time, and intensity of curve fluctuation from the curves.

[0017] S6. Evaluate the range hood's ability to capture oil fumes.

[0018] Preferably, S2 and S3 are performed simultaneously.

[0019] Preferably, in step S5, before converting the scattered laser image sequence of the oil fume aerosol concentration field into a grayscale image, the scattered laser image sequence of the oil fume aerosol concentration field is further preprocessed, the preprocessing including image correction and background removal.

[0020] Preferably, the laser generates a sheet-like laser plane, which is respectively attached to multiple surfaces of the smoke collection interface.

[0021] Compared with existing technologies, the beneficial effects of the oil fume generating device described in this invention are mainly reflected in the following aspects: It provides a standard oil fume source through an aerosol generation system, outputting repeatable and stable oil fume aerosols. After being heated, the oil fume aerosols are released through a porous flow field component to form an oil fume jet plume, simulating the dynamic oil fume flow field of real cooking. The oil fume jet plume can be repeatedly output, enabling accurate comparison of detection results and improving the accuracy of detecting the oil fume capture capability of the range hood. Simultaneously, the amount of oil fume particles generated, the oil fume jet plume, and the heating airflow are controllable. This allows for controllable simulation of the concentration, temperature, release form, and diffusion process of oil fumes under different cooking conditions, enabling the detection of the comprehensive performance of the range hood under different cooking conditions.

[0022] Compared with existing technologies, the beneficial effects of the oil fume collection capacity testing method for range hoods described in this invention are mainly reflected in the following aspects: Utilizing the optical scattering method for detection, non-contact detection is achieved, which does not interfere with the direction of oil fume airflow. The oil fume collection capacity of the range hood is comprehensively evaluated by considering the total amount of oil fume escape, the oil fume escape time ratio, the oil fume escape area ratio, and the curve fluctuation intensity. The total amount of oil fume escape reflects the average scattered light intensity, indicating the overall mass concentration of the escaped oil fumes. The oil fume escape area ratio reflects the actual area of ​​escaped oil fumes. The oil fume escape time ratio reflects the total time of oil fume escape. The curve fluctuation intensity reflects the working stability of the range hood. The lower the value of the total amount of oil fume escape, the smaller the oil fume escape area ratio, the smaller the oil fume escape time ratio, and the smaller the curve fluctuation intensity, the better the oil fume collection capacity of the range hood. Attached Figure Description

[0023] The above and other objects, features, and advantages of the invention will become clearer through a more detailed description of the preferred embodiments illustrated in the accompanying drawings. The same reference numerals denote the same parts throughout the drawings, and the drawings are not intentionally drawn to scale with actual dimensions; the focus is on illustrating the gist of the invention.

[0024] Figure 1 This is a schematic diagram of the fume generating device in Embodiment 1 of the present invention.

[0025] Figure 2 This is a cross-sectional view of the fume generating device in Embodiment 1 of the present invention.

[0026] Figure 3 This is a schematic diagram of the kitchen simulation system in Embodiment 2 of the present invention.

[0027] Figure 4 This is a schematic diagram of the range hood and smoke collection interface in this invention.

[0028] Figure 5 This is a schematic diagram of the laser and the sheet-like laser plane in this invention.

[0029] Figure 6 This is a schematic diagram showing the position of the camera device and the captured image in this invention.

[0030] Explanation of icon numbers:

[0031] Aerosol generating system 1, oil fume sprayer 11, first fan 12.

[0032] Flow field and temperature field generation system 2, porous flow field component 21, second fan 22, heating tube 23, honeycomb rectifier 24, output port 25, air outlet 26.

[0033] Smoke exhaust duct 3.

[0034] Range hood 4, first interface 41, second interface 42, third interface 43.

[0035] Laser 5, first laser 51, second laser 52, third laser 53, first sheet-like laser plane 54, second sheet-like laser plane 55, third sheet-like laser plane 56.

[0036] Camera device 6, first camera device 61, second camera device 62, third camera device 63. Detailed Implementation

[0037] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention. In this embodiment, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0038] It should be noted that when one element is considered to be "connected" to another element, it can be directly connected to and integrated with the other element, or there may be an intervening element present. The terms "mounted," "one end," "the other end," and similar expressions used in this invention are for illustrative purposes only.

[0039] Example 1

[0040] like Figure 1-6As shown, an oil fume generating device includes an aerosol generating system 1, a flow field and temperature field generating system 2, and an exhaust pipe 3. The aerosol generating system 1 is connected to the input end of the exhaust pipe 3. The aerosol generating system 1 is used to generate oil fume particles and control the amount of oil fume particles generated. The aerosol generating system 1 is also used to introduce air to mix with the oil fume particles to form oil fume aerosols and control the amount of air mixed to adjust the total amount of oil fume aerosols.

[0041] The flow field and temperature field generation system 2 includes a temperature field component and a porous flow field component 21. The output end of the exhaust pipe 3 is connected to the porous flow field component 21. The temperature field component is sleeved on the outside of the exhaust pipe 3. The end of the temperature field component near the porous flow field component 21 is provided with an output port 25. The temperature field component generates a heated airflow and controls the amount of air and heat of the heated airflow. The heated airflow is discharged from the output port 25. The oil fume aerosol is heated by the temperature field component and discharged through the porous flow field component 21 to form an oil fume jet plume.

[0042] The aerosol generation system 1 provides a standard source of cooking fumes and outputs repeatable and stable aerosols. After being heated, the aerosols are released through the porous flow field component 21 to form a plume of cooking fumes, simulating the dynamic flow field of cooking fumes. The plume of cooking fumes can be repeatedly output, allowing for accurate comparison of test results and improving the accuracy of testing the fume collection ability of the range hood 4. At the same time, the amount of fume particles generated, the plume of cooking fumes, and the heating airflow are all controllable. This allows for the controllable simulation of the concentration, temperature, release form, and diffusion process of cooking fumes under different cooking conditions, enabling the comprehensive performance of the range hood 4 under different cooking conditions to be tested.

[0043] The aerosol generation system 1 includes an oil fume sprayer 11 and a first fan 12, both of which are connected to the input end of the exhaust duct 3. The oil fume sprayer 11 is used to generate oil fume particles and control the amount of oil fume particles generated; the first fan 12 is used to introduce air to mix with the oil fume particles to form an oil fume aerosol and control the amount of air mixed.

[0044] In a preferred embodiment, the fume atomizer 11 generates DEHS (dioctyl sebacate) oil mist particles with a particle size range of 0.1-10 μm as a simulated oil fume. The fume atomizer 11 is equipped with an oil pump and an oil-water heating chamber, and the amount of oil fume particles generated is controlled by adjusting the oil supply of the oil pump and the power of the oil-water heating chamber. In a preferred embodiment, a Raskin nozzle is provided at the output end of the fume atomizer 11.

[0045] The temperature field component includes a second fan 22, a heating tube 23, and a honeycomb rectifier 24. The honeycomb rectifier 24 is fitted outside the exhaust duct 3. The second fan 22 is connected to the heating tube 23, and the heating tube 23 is connected to the honeycomb rectifier 24. The second fan 22 is used for air supply and pressurization, and the heating tube 23 is used to heat the air to form a heated airflow. Under the action of the honeycomb rectifier 24, the heated airflow forms a stable and uniform airflow, simulating the high-temperature smoke produced by a gas stove. The porous flow field component 21 is a porous smoke pot. Air outlets 26 are evenly distributed at the output end of the porous smoke pot; the output port 25 is arranged in a ring shape.

[0046] In a preferred embodiment, a feedback system is further included, comprising a temperature sensor (not shown) and an airflow velocity sensor (not shown); the temperature sensor and the airflow velocity sensor are disposed within the exhaust duct 3. Feedback from the temperature sensor and the airflow velocity sensor facilitates control of the amount of oil fume particles generated, the power of the first fan, the power of the second fan, and the power of the heating element.

[0047] Example 2

[0048] like Figure 3 As shown, in this embodiment, the fume generator is used in the kitchen simulation system, which also includes a range hood 4, a common flue, a bottom fan, and an exhaust fan.

[0049] The range hood 4 is installed above the fume generating device. The exhaust port of the range hood 4 is equipped with a flow meter and a pressure sensor. The exhaust port of the range hood 4 is connected to a common flue. The common flue is also connected to an exhaust fan and a bottom fan. A pressure sensor is installed in the common flue. The range hood 4 exhausts the fumes into the common flue. The fumes entering the common flue are discharged outdoors by the exhaust fan and the bottom fan.

[0050] A method for testing the oil fume collection capacity of a range hood includes the following steps:

[0051] S1. Pre-installed fume generator and range hood 4; preset fume collection interface; pre-installed laser and camera device, the camera device lens is equipped with a filter group. The filter group is used to suppress the light generated by the corresponding laser, allowing only the laser generated by the corresponding laser to pass through.

[0052] S2. Start the fume generator, range hood 4, and laser.

[0053] S3. The laser illuminates the smoke collection interface, and the camera device collects a sequence of scattered laser images of the oil fume aerosol concentration field.

[0054] S4. Preset a quantitative relationship model between image thickness and oil fume concentration; convert the laser image sequence into a grayscale image to obtain the image grayscale information of oil fume concentration for each frame of grayscale image. The image grayscale information of oil fume concentration includes the average grayscale value of oil fume concentration and the ratio of oil fume escape area to the area of ​​the smoke collection interface.

[0055] S5. Establish curves showing the changes in average oil fume concentration, oil fume escape area, and total oil fume mass over time, and extract information on the ratio of total oil fume escape, ratio of oil fume escape area, ratio of oil fume escape time, and intensity of curve fluctuation from the curves.

[0056] S6. Evaluate the oil fume collection ability of range hood 4.

[0057] The above method utilizes optical scattering for detection, achieving non-contact detection without interfering with the airflow direction of the cooking fumes. The range hood 4's fume collection capability is comprehensively evaluated by considering the total amount of fume escape, the fume escape time ratio, the fume escape area ratio, and the curve fluctuation intensity. The total amount of fume escape reflects the average scattered light intensity, indicating the overall mass concentration of the escaped fumes. The fume escape area ratio reflects the actual area of ​​escaped fumes. The fume escape time ratio reflects the total time of fume escape. The curve fluctuation intensity reflects the operational stability of the range hood 4. The lower the total amount of fume escape, the smaller the fume escape area ratio, the smaller the fume escape time ratio, and the smaller the curve fluctuation intensity, the better the fume collection capability of the range hood 4.

[0058] In the above S1, a fume generator and a range hood 4 are pre-installed; this includes setting up a detection area, placing the range hood 4 above the detection area, and placing the fume generator in the detection area; the range hood 4 is placed above the fume generator.

[0059] The preset smoke collection interface is specifically set on the plane where the smoke collection structure of the range hood 4 is located.

[0060] In this embodiment, the smoke collection interface includes a first interface 41, a second interface 42, and a third interface 43; the first interface 41 is located on the plane of the left side wall of the range hood 4 and extends downward; the second interface 42 is located on the plane of the right side wall of the range hood 4 and extends downward; the third interface 43 is connected to the first interface 41 and the second interface 42, and intersects with the top edge of the range hood 4.

[0061] The laser 5 generates a sheet-like laser plane, which is respectively attached to multiple surfaces of the smoke-collecting interface. Specifically, the laser is pre-installed by attaching or partially overlapping the sheet-like laser plane generated by the laser with the smoke-collecting interface.

[0062] In this embodiment, there are three lasers 5, namely a first laser 51, a second laser 52 and a third laser 53. The first laser 51 corresponds to the first interface 41, the second laser 52 corresponds to the second interface 42, and the third laser 53 corresponds to the third interface 43.

[0063] The first sheet-like laser plane 54 generated by the first laser 51 is perpendicular to the detection area and partially overlaps with the first interface 41. In this embodiment, the area of ​​the first sheet-like laser plane 54 is larger than the area of ​​the first interface 41.

[0064] The second sheet-like laser plane 55 generated by the second laser 52 is perpendicular to the detection area and partially coincides with the second interface 42. In this embodiment, the area of ​​the second sheet-like laser plane 55 is larger than the area of ​​the second interface 42.

[0065] The third sheet-like laser plane 56 generated by the third laser 53 is tilted relative to the detection area, and partially overlaps with the third interface 43. In this embodiment, the area of ​​the third sheet-like laser plane 56 is larger than the area of ​​the third interface 43. The first sheet-like laser plane 54, the second sheet-like laser plane 55, and the third sheet-like laser plane 56 cover the smoke collection interface, thus enabling clear acquisition of images of oil fume escape.

[0066] The camera device is pre-installed, specifically by mounting it on the outside of the sheet-like laser plane. The camera device is located on the vertical line of the center point of the smoke collection interface, thus ensuring that the flow of oil fumes in the smoke collection interface is located in the center area of ​​the image.

[0067] The camera device 6 has three parts: a first camera device 61, a second camera device 62, and a third camera device 63. The first camera device 61 corresponds to the first sheet-like laser plane 54 and the first interface 41; the second camera device 62 corresponds to the second sheet-like laser plane 55 and the second interface 42; and the third camera device 63 corresponds to the third sheet-like laser plane 56 and the second interface 43.

[0068] In a preferred embodiment, S2 and S3 are performed simultaneously. A sheet-like laser illuminates the detection area, and the camera simultaneously acquires a sequence of laser images scattered by the oil fume particles. The entire process is synchronized with the occurrence of the oil fume, ensuring the complete capture of the oil fume diffusion and collection process.

[0069] The above S4 specifically includes the following steps:

[0070] S4.1. Start the range hood 4 and the laser. Collect images through the camera device and remove the average to obtain a background image. The background image contains interference information, including ambient light, non-uniform laser light path, and inherent dark noise of the camera.

[0071] S4.2 Subtract the background image from each frame of the scattered laser image sequence of the oil fume aerosol concentration field to obtain a grayscale image for each frame. The grayscale image is a net scattered light image, which removes fixed noise and makes the grayscale image reflect only the scattering signal of the oil fume particles.

[0072] S4.3 Calculate the average gray value G_measured of the grayscale image.

[0073] S4.4. Obtain the true mass concentration of the current oil fume using a benchmark measurement method; In this embodiment, the benchmark measurement method is the filter membrane weighing method, which involves passing a known volume of gas through a filter membrane, weighing the mass difference before and after the filter membrane, and calculating the absolute mass concentration C_standard.

[0074] By pre-setting the generation amount of the oil fume jet and the heating airflow, a constant oil fume jet and heating airflow are generated through the oil fume generator, thus determining the current volume of oil fumes.

[0075] S4.5. Establish data pairs (C_standard, G_measured).

[0076] S4.6 Fit the data pairs to obtain a quantitative relationship model C=a*G+b between image thickness and oil fume concentration.

[0077] S4.7. Calculate the oil fume concentration value at the corresponding pixel position in the grayscale image by using the quantitative relationship model C=a*G+b between the grayscale value of each pixel in the grayscale image, the image thickness, and the oil fume concentration; and obtain the two-dimensional concentration distribution field K(x, y, t) of the oil fume on the sheet-like laser plane at the current moment.

[0078] S4.8 Calculate the average oil fume mass concentration of all pixels within the smoke collection interface.

[0079] S4.9 Set a concentration threshold, which is less than 50% of the average concentration of oil fume; define the area within the smoke collection interface that is less than or equal to the concentration threshold as the oil fume escape zone, and calculate the ratio of the pixel area of ​​the oil fume escape zone to the area of ​​the smoke collection interface; obtain the ratio of the oil fume escape area to the area of ​​the smoke collection interface.

[0080] S4.10. Spatial integration is performed on the region outside the smoke collection interface where the concentration is greater than the concentration threshold to obtain the single-frame escape mass. Then, temporal integration is performed on all frames to obtain the total escape mass of the oil fume during the entire detection process.

[0081] Preferably, the curve fluctuation intensity information includes the fluctuation intensity of the total escape ratio of oil fumes and the fluctuation intensity of the escape area ratio of oil fumes. The following table provides examples of extracting the total escape ratio of oil fumes, the escape area ratio of oil fumes, the escape time ratio of oil fumes, and the curve fluctuation intensity information from the curve.

[0082]

[0083] Table 1

[0084] The comprehensive evaluation parameters of the fume collection energy of range hood 4 are obtained by adding the total fume escape ratio, the fume escape area ratio, and the fume escape time ratio. The working stability evaluation parameters of the fume collection capacity of range hood 4 are obtained by adding the fluctuation intensity of the total fume escape ratio and the fluctuation intensity of the fume escape area ratio.

[0085] In step S4 above, before converting the scattered laser image sequence of the oil fume aerosol concentration field into a grayscale image, the scattered laser image sequence of the oil fume aerosol concentration field is preprocessed, including image correction and background removal.

[0086] The image correction is a geometric correction used to eliminate image distortion and establish a precise correspondence between image pixel coordinates and actual physical space coordinates, ensuring the accuracy of subsequent measurements of physical quantities such as area and distance.

[0087] Geometric correction includes intrinsic parameter correction and extrinsic parameter correction. Intrinsic parameter correction uses a high-precision calibration plate (such as a checkerboard or dot array) to capture multiple images of the calibration plate from different angles within the camera's field of view. The intrinsic parameter matrix (including focal length and principal point coordinates) and distortion coefficients of the camera are calculated using a calibration algorithm. The obtained parameters are then used to perform distortion correction on the subsequently acquired sequence of scattered laser images of the oil fume aerosol concentration field, resulting in distortion-free images.

[0088] The extrinsic correction, under smoke-free conditions, involves placing a calibration object of known size (such as a graduated ruler or a plate with a specific pattern) into the sheet-like laser plane to achieve a clear image. By identifying feature points on the calibration object through image recognition and combining them with its known physical dimensions, the equation of the sheet-like laser plane in the coordinate system of the camera device is calculated.

[0089] In this specification, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0090] In the description of this specification, the references to terms such as "preferred embodiment," "another embodiment," "other embodiment," or "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0091] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A fume generating device, characterized in that: It includes an aerosol generation system, a flow field and temperature field generation system, and a smoke exhaust duct. The aerosol generation system is connected to the input end of the smoke exhaust duct. The aerosol generation system is used to generate oil fume particles and control the amount of oil fume particles generated. The aerosol generation system is also used to mix oil fume particles with air to form oil fume aerosols and control the amount of air mixed to adjust the total amount of oil fume aerosols. The flow field and temperature field generation system includes a temperature field component and a porous flow field component. The output end of the exhaust duct is connected to the porous flow field component, and the temperature field component is fitted outside the exhaust duct. The end of the temperature field component near the porous flow field component has an output port. The temperature field component generates heated airflow and controls the amount of air and heat of the heated airflow. The heated airflow is discharged from the output port. The oil fume aerosol is heated by the temperature field component and discharged through the porous flow field component to form an oil fume jet plume.

2. The fume generating device according to claim 1, characterized in that: The temperature field component includes a second fan, a heating tube, and a honeycomb rectifier. The honeycomb rectifier is sleeved outside the exhaust duct. The second fan is connected to the heating tube, and the heating tube is connected to the honeycomb rectifier.

3. The fume generating device according to claim 2, characterized in that: The output port is arranged in a ring shape.

4. The fume generating device according to claim 1, characterized in that: The aerosol generating system includes an oil fume sprayer and a first fan, both of which are connected to the input end of the exhaust duct.

5. A method for detecting the oil fume collection capacity of a range hood, comprising the oil fume generating device as described in any one of claims 1-4, characterized in that: Includes the following steps: S1. Pre-installed fume generator and range hood; pre-set fume collection interface; pre-installed laser and camera device, with the camera device lens equipped with a filter group; S2. Start the fume generator, range hood, and laser; S3. The laser illuminates the smoke collection interface, and the camera device collects the scattered laser image sequence of the oil fume aerosol concentration field. S4. Preset a quantitative relationship model between image thickness and oil fume mass concentration; convert the scattered laser image sequence of oil fume aerosol concentration field into a grayscale image to obtain the image grayscale information of oil fume concentration in each frame of grayscale image. The image grayscale information of oil fume concentration includes the average grayscale value of oil fume mass concentration and the ratio of oil fume escape area to the area of ​​the smoke collection interface. S5. Establish curves showing the changes in average oil fume concentration, oil fume escape area, and total oil fume mass over time, and extract information on the total oil fume escape ratio, oil fume escape area ratio, oil fume escape time ratio, and curve fluctuation intensity from the curves. S6. Evaluate the range hood's ability to capture oil fumes.

6. The method for detecting the oil fume collection capacity of a range hood according to claim 5, characterized in that: S2 and S3 proceed simultaneously.

7. The method for testing the oil fume collection capacity of a range hood according to claim 5, characterized in that: In step S5, before converting the scattered laser image sequence of the oil fume aerosol concentration field into a grayscale image, the scattered laser image sequence of the oil fume aerosol concentration field is preprocessed, including image correction and background removal.

8. The method for detecting the oil fume collection capacity of a range hood according to claim 5, characterized in that: The laser generates a sheet-like laser plane, which is then attached to multiple surfaces of the smoke collection interface.

Images