Patent Application
20240118183
This application is based on and claims priority to Korean Patent Application No. 10-2022-0124885, filed on Sep. 30, 2022, in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety.
The disclosure relates to a fine dust measurement module that can identify fine dust contained in the air, by classifying the fine dust by diameter, and a fine dust measurement device including the fine dust measurement module.
Dust is classified into total suspended particles (TSP) of particle sizes of 50 μm or less and fine particles of very small particle sizes, depending on the size of the particles. Fine particles or fine dust is classified into fine dust of particulate matter (PM) 10 (i.e., PM10, sometimes classified as fine dust) with a diameter of less than 10 um and fine dust of PM2.5 (sometimes classified as ultrafine dust) with a diameter of less than 2.5 um depending on the size of the particles.
Since fine dust causes environmental pollution and health problems such as damage to the respiratory system of the human body, technologies that measure and provide fine dust concentration are required along with reducing fine dust. In particular, a virtual impactor may be used to measure the concentration of fine dust by classifying fine dust according to the size of the particles of the fine dust.
In the process of measuring the concentration of fine dust using a virtual impactor, there is a concern that the time for measuring the concentration of fine dust by collecting fine dust classified by diameter may increase.
Provided are a fine dust measurement module and a fine dust measurement device including the fine dust measurement module, which may quickly and effectively identify fine dust, by classifying fine dust contained in the air by diameter and collecting the classified fine dust.
Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments.
According to an aspect of an example embodiment, a fine dust measurement module may include a fluid inlet through which a fluid including fine dust is introduced, a first channel through which first fine dust having at least a first diameter, among the fine dust introduced into the fluid inlet, passes, a second channel through which second fine dust having a second diameter that is less than the first diameter, among the fine dust introduced into the fluid inlet, passes, a fine dust detection sensor for sensing fine dust flowing into the second channel, a heater above the fine dust detection sensor, and an orifice upstream of a flow of the second fine dust from the fine dust detection sensor and the heater.
A diameter of the orifice may be configured such that a Stokes number for the second fine dust is in a range of about 0.9 to about 1.05.
The measurement module may include a first inclined portion at a front end of the orifice and having a first inclination angle.
The measurement module may include a second inclined portion at a rear end of the orifice and having a second predetermined inclination angle.
The orifice may include a plurality of orifices including the orifice, and the plurality of orifices may be each spaced apart from each other at an interval along the flow of the second fine dust.
The fine dust detection sensor and the heater may be provided at a rear end of a first orifice of the plurality of orifices that is downstream of the flow of the second fine dust.
The fine dust detection sensor may include a mass detection sensor configured to directly sense a mass of fine dust introduced into the second channel.
A ratio of a first flow rate of the fluid introduced into the first channel to a second flow rate of the fluid introduced into the second channel may be 1:9.
The measurement module may include a flow rate ratio control nozzle in the first channel, where the flow rate ratio control nozzle is configured to adjust a ratio of a first flow rate of fluid introduced into the first channel a second flow rate of fluid introduced into the second channel.
The second channel may include a first sub-channel, a second sub-channel, the first sub-channel and the second sub-channel being branched from each other and around the first channel, and a third sub-channel into which the first sub-channel and the second sub-channel are merged.
The fine dust detection sensor may be arranged in the third sub-channel.
The first channel may include a first sub-channel on a same plane as that of the second channel, a second sub-channel connected to the first sub-channel and on a plane different from that of the second channel, and a third sub-channel connected to the second sub-channel and on a same plane as that of the second channel.
The first channel may include a first connector connecting the first sub-channel with the second sub-channel channel, and a second connector connecting the second sub-channel with the third sub-channel.
The measurement module may include a third channel into which the first channel and the second channel are merged, and a discharge component connected to the third channel and from which the fluid is discharged.
A ratio of a second pressure inside the discharge component to a first pressure inside the third channel is less than or equal to 0.528.
The measurement module may include a choked nozzle between the third channel and the discharge component.
The measurement module may include a pump connected to the discharge component, and configured to adjust an internal pressure of the discharge component.
According to an aspect of an example embodiment, a fine dust measurement device may include a plurality of fine dust measurement modules, each of the plurality of fine dust measurement modules including a fluid inlet through which a fluid including fine dust is introduced, a first channel through which first fine dust having at least a first diameter, among the fine dust introduced into the fluid inlet, passes, a second channel through which second fine dust having a diameter that is less than the first diameter, among the fine dust introduced into the fluid inlet, passes, a fine dust detection sensor configured to sense fine dust flowing into the second channel, a micro heater above the fine dust detection sensor, and an orifice upstream of a flow of the second fine dust from the fine dust detection sensor and the micro heater, and a discharge component connected to each of the plurality of fine dust measurement modules and configured to discharge fluid.
The plurality of fine dust measurement modules may include a first fine dust measurement module, a second fine dust measurement module, and a third fine dust measurement module, and the first fine dust measurement module, the second fine dust measurement module, and the third fine dust measurement module may be arranged in parallel.
The measurement device may include a pump connected to the discharge component, and configured to adjust an internal pressure of the discharge component.
According to an aspect of an example embodiment, a fine dust measurement module may include a first channel through which first fine dust having at least a first diameter passes, a second channel through which second fine dust having a second diameter that is less than the first diameter passes, and an orifice upstream of a flow of the second fine dust, where the second channel includes a first sub-channel, a second sub-channel, the first sub-channel and the second sub-channel being branched from each other and around the first channel, and a third sub-channel into which the first sub-channel and the second sub-channel are merged.
The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:
Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, in which like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.
The disclosure may apply various transforms and have various embodiments, and particular embodiments are illustrated in the drawings and will be described in detail in the detailed description with reference to the illustrated drawings. The effects and features of the disclosure, and methods of achieving the effects and features, will become apparent with reference to the embodiments described in detail with reference to the drawings. However, the disclosure is not limited to the embodiments disclosed below, but may be implemented in various forms.
Hereinafter, embodiments of the disclosure will be described in detail with reference to the accompanying drawings, and the same or corresponding components will be denoted by the same reference numerals and redundant descriptions thereof will be omitted.
In the following embodiments, when one of various components such as layers, membranes, regions, and plates are said to be “on” another component, this includes not only the case where the one component is “directly on” the other component, but also the case where a third component is placed therebetween. In addition, for convenience of explanation, components may be exaggerated or reduced in size in the drawings. For example, since the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of explanation, the disclosure is not necessarily limited to those illustrated.
In the following embodiments, the x-axis, the y-axis, and the z-axis are not limited to three axes on the orthogonal coordinate system, and may be interpreted as a wide meaning including the same. For example, the x-axis, y-axis, and z-axis may be orthogonal to each other, but may also refer to different directions that are not orthogonal to each other.
Referring to
The fluid inlet 100 is a fluid inlet passage through which fluid Ain including fine dust may be introduced. The fluid Ain including the fine dust is a gas including particles, and may be understood as a concept including, for example, polydisperse aerosol. In addition, the fluid Ain introduced into the fluid inlet 100 may include fine dust or ultrafine dust having various diameters. Fine dust or ultrafine dust is distinguished based on the diameter of the particle.
The fluid inlet 100 according to an embodiment may be arranged on the first channel 110 and the second channel 120. Specifically, the fluid inlet 100 may be formed on an upper portion of the first channel 110 and the second channel 120 in a direction facing the first channel 110. In this case, the fluid inlet 100 may have a diameter greater than that of the first channel 110. However, the present disclosure is not limited thereto, and the fluid inlet 100 may have a diameter smaller than or equal to that of the first channel 110.
The fluid Ain introduced into the fluid inlet 100 is lowered and moved in a vertical direction by inertia. In this case, particles with great inertia among the aerosol particles included in the fluid Ain may be discharged to the first channel 110, and particles with less inertia among the aerosol particles may be discharged to the second channel 120. The first flow may act as a minor flow and the second flow may act as a major flow.
The first channel 110 may classify, according to inertia, aerosol particles included in the fluid Ain introduced into the fluid inlet 100. In this case, the first channel 110 may classify first fine dust (e.g., particles having great inertia) having a diameter greater than or equal to a first diameter (e.g., the first diameter may be used as a reference for classifying particle size). The value of the first diameter may be determined by the ratio of the flow rate of the first channel 110 to the flow rate of the second channel 120.
A portion of the first channel 110 according to an embodiment may be formed on a different plane from the second channel 120. As an example, as shown in
The second channel 120 may classify, according to inertia, aerosol particles included in the fluid Ain introduced into the fluid inlet 100. In this case, the second channel 120 may classify second fine dust (e.g., particles with less inertia) having a diameter that is less than the first diameter.
The second channel 120 according to an embodiment may include the first sub-channel 121 and the second sub-channel 122, which are branched from each other around the first channel 110, and the third sub-channel 123 into which the first sub-channel 121 and the second sub-channel 122 are merged. As an example, as shown in
The third sub-channel 123 may be formed by merging the first sub-channel 121 and the second sub-channel 122. In this case, the second fine dust (e.g., having particles with less inertia) having diameters less than the first diameter classified in the fine dust classification area C may be collected in the third sub-channel 123. As shown in
The flow rate ratio control nozzle 130 may be arranged in the first channel 110 to adjust the flow rate ratio of the fluid introduced into the first channel 110 and the second channel 120. As an example, as shown in
The third channel 150 may be a merged channel in which the first fluid A1 passing through the first channel 110 and the second fluid A2 passing through the second channel 120 are merged. As an example, the third channel 150 may be arranged to be in fluid communication with the discharge component 180 with the choked nozzle 185 therebetween.
The fine dust detection sensor 160 is a detection unit that detects the concentration of the second fine dust (e.g., having particles with less inertia) introduced into the second channel 120. As an example, the fine dust detection sensor 160 may employ a weight measurement method, a beta ray measurement method, a light scattering measurement method, or the like for directly measuring the mass of fine dust, but the present disclosure is not limited thereto. The fine dust detection sensor 160 according to an embodiment may be implemented as a mass detection sensor that directly measures the mass of fine dust, and the mass detection sensor may use one or more of a surface acoustic wave measurement method, a bulk acoustic wave measurement method, and a quartz crystal microbalance measurement method.
As described above, a portion of the first channel 110 may be arranged on a plane different from that of the second channel 120, and the third sub-channel 123 into which the first sub-channel 121 and the second sub-channel 122 merge may be formed. In this case, the fine dust detection sensor 160 may be arranged in the third sub-channel 123. Accordingly, it may not be necessary to separately arrange the fine dust detection sensor 160 in the first sub-channel 121 and the second sub-channel 122, and the concentration of the second fine dust (e.g., having particles with less inertia) may be measured using one fine dust detection sensor 160.
The micro heater 170 may be a heating unit that applies heat to the second fine dust (e.g., having particles with less inertia) introduced into the second channel 120. The micro heater 170 according to an embodiment may be arranged above the fine dust detection sensor 160 to apply heat to the second fine dust (e.g., having particles with less inertia) introduced into the second channel 120. In this case, the second fine dust (e.g., having particles with less inertia) may be collected in the fine dust detection sensor 160 due to a thermophoretic effect.
The discharge component 180 may be a discharge member capable of discharging, to the outside, the fluid Aout whose concentration of the second fine dust (e.g., having particles with less inertia) has been measured. As an example, the discharge component 180 may be arranged to be in fluid communication with the third channel 150 with the choked nozzle 185 therebetween. The internal pressure of the discharge component 180 may be adjusted by the pump 190 (see
The orifice 200 may collect the second fine dust collected by the fine dust detection sensor 160 by making the stream of the second fine dust (e.g., having particles with less inertia) introduced into the second channel 120 in a straight line. The orifice 200 according to an embodiment may be arranged in the second channel 120, for example, the third sub-channel 123, and may be arranged upstream of the flow of the second fine dust from the fine dust detection sensor 160 and the micro heater 170. Accordingly, the stream of second fine dust collected between the fine dust detection sensor 160 and the micro heater 170 passes, so that the second fine dust may be quickly collected in the fine dust detection sensor 160.
According to an embodiment, the ability to collect second fine dust included in the second fluid A2 may be determined according to the Stokes number of the second fine dust. Hereinafter, the second fine dust collected according to the Stokes number will be described with reference to
Referring to
For example, the second fluid A2 introduced into the second channel 120 may be introduced into the third sub-channel 123 through the first sub-channel 121 and the second sub-channel 122. In this case, the third sub-channel 123 may have a predetermined width H to allow the second fluid A2 to move. According to an embodiment, the orifice 200 may have a diameter D smaller than the width H of the second channel 120, for example, the third sub-channel 123. According to an embodiment, the second fluid A2 introduced into the third sub-channel 123 is contracted upstream of the orifice 200 while passing through the orifice 200, and then expanded downstream of the orifice 200. According to an embodiment, as the second fluid A2 passes through the orifice 200, the second fine dust having a predetermined diameter may be collected in a straight line direction.
According to an embodiment, as the second fluid A2 approaches the orifice 200 and passes through the orifice 200, contraction is generated in the stream of the second fluid A2. For example, a first inclined portion 210 having a predetermined inclination angle may be arranged in a front end of the orifice 200. The first inclined portion 210 may have a first inclination angle α from the front end of the orifice 200. For example, the first inclination angle α may be about 45 degrees or more and less than about 90 degrees. When the first inclined portion 210 is arranged in the front end of the orifice 200, a cross-sectional area through which the second fluid A2 passes upstream of the orifice 200 may be reduced. Accordingly, as the second fluid A2 contracts upstream of the orifice 200, the second fluid A2 facing the orifice 200 may be collected.
Thereafter, as the second fluid A2 passes through the orifice 200 and enters an area having a wider cross-sectional area, the second fluid A2 may be expanded. For example, a second inclined portion 220 having a predetermined inclination angle may be arranged in a rear end of the orifice 200. The second inclined portion 220 may have a second inclination angle α from a rear end of the orifice 200. For example, the second inclination angle β may be about 45 degrees or more and less than about 90 degrees. When the second inclined portion 220 is arranged in the rear end of the orifice 200, a cross-sectional area through which the second fluid A2 passes downstream of the orifice 200 may be reduced. Accordingly, the vortex generated downstream of the orifice 200 may be alleviated.
According to an embodiment, at least one of the first inclined portion 210 and the second inclined portion 220 may be arranged in a front end or a rear end of the orifice 200. For example, the first inclined portion 210 may be placed at the front end of the orifice 200, the second inclined portion 220 may be placed at the rear end of the orifice 200, or the first inclined portion 210 and the second inclined portion 220 may be placed at the front and rear ends of the orifice 200.
As described above, the ability to collect second fine dust having a predetermined diameter included in the second fluid A2 may be determined according to the Stokes number of the second fine dust according to Equation (1):
where, D may be the diameter of the orifice, ρp may be the density of the second fine dust, dp may be the diameter of the second fine dust, Cc may be the Cunningham slip correction factor, μ may be the viscosity of the second fluid, and ∪ may be the flow velocity of the second fluid.
According to an embodiment, the second fine dust having a predetermined diameter dp may be collected toward a numerical value in which the Stokes number is adjacent to 1, for example, a straight line formed at the central portion in a range of about 0.9 or more and about 1.05 or less. When the Stokes number of the second fine dust having a predetermined diameter dp deviates from 1, for example, when the Stokes number is less than about 0.9 and greater than about 1.05, the second fine dust may spread outside a straight line formed at the central portion.
According to an embodiment, when the concentration of the second fine dust is measured using the fine dust detection sensor 160, the diameter D of the orifice 200 may be determined such that the Stokes number for the second fine dust is about 0.9 or more and about 1.05 or less. According to an embodiment, when the Stokes number for the second fine dust is about 0.9 or more and about 1.05 or less, the second fine dust passing through the orifice 200 may be collected toward one straight line formed at the central portion. Accordingly, the second fine dust may be quickly detected by collecting the second fine dust between the fine dust detection sensor 160 and the micro heater 170 arranged downstream of the orifice 200 along the flow of the second fine dust.
Referring to
Referring to
According to an embodiment shown in
According to the comparative example shown in
Referring to
The fine dust detection sensor 160 and the micro heater 170 according to an embodiment may be arranged at the rear end of the plurality of orifices 200-A arranged downstream of the flow of the second fine dust. For example, as shown in
As described above, since the plurality of orifices 200-A are arranged in the second channel 120, the effect of collecting the second fine dust toward one straight line formed at the central portion may be improved. For example, as the second fluid A2 introduced into the second channel 120 sequentially passes through the first orifice 200-1 and the second orifice 200-2, the effect of collecting the second fine dust toward the straight line formed at the central portion may be sequentially improved. Accordingly, it is possible to detect the second fine dust more quickly by placing the plurality of orifices 200-A than placing a single orifice (e.g., orifice 200 of
Referring back to
Referring to
Referring to
According to an embodiment, the first diameter of fine dust classified by the first fine dust measurement module 10-1, the second diameter of fine dust classified by the second fine dust measurement module 10-2, and the third diameter of fine dust classified by the third fine dust measurement module 10-3 may be different. The diameters of fine dust classified in the first to third fine dust measurement modules 10-1 to 10-3 may be differently determined depending upon the cross-sectional areas of the connectors connecting the fluid inlet with the channels, respectively.
As an example, the pressure inside the third channel and the pressure inside the discharge component provided in each of the first to third fine dust measurement modules 10-1 to 10-3 may be adjusted using a cross-sectional area of the choked nozzle provided in each of the first to third fine dust measurement modules 10-1 to 10-3 and the pump connected to the discharge component 80. That is, by adjusting the relative pressure using the cross-sectional area of the choked nozzle provided in each of the first to third fine dust measurement modules 10-1 to 10-3 and the one pump connected to the discharge component 80-1, the flow rate of the fluid flowing in the first to third fine dust measurement modules 10-1 to 10-3 may be uniformly controlled, thereby increasing the measurement accuracy of fine dust.
One or more embodiments provide a fine dust detection module and a fine dust measurement device including same, the fine dust detection module allowing fine dust to be quickly collected by a fine dust detection sensor (mass sensor) by collecting fine dust through an orifice in a process of measuring fine dust using a fine dust measurement module, thereby quickly and effectively detecting fine dust.
According to an embodiment of the disclosure as described above, it is possible to implement a fine dust measurement module and a fine dust measurement device that are simple in configuration and may classify fine dust in the air by diameter and collect and identify the classified fine dust quickly and effectively. However, the scope of the disclosure is not limited by such an effect.
It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2022-0124885 | Sep 2022 | KR | national |
