KR20220146257A - Fluid duct device for vehicle capable of reducing air flow resistance - Google Patents

Abstract

The present invention relates to a fluid duct device for a vehicle capable of reducing an air flow resistance, which can change the flow of fluid in a vehicle into a combination of vortex and straight air flow, significantly reduce an air flow resistance to form a high speed air flow so that the high speed air flow is sucked into an engine of the vehicle, thereby completely burning the fuel of the vehicle and increasing fuel efficiency. In particular, the fluid duct device for a vehicle capable of reducing an air flow resistance can provide a greater effect in the vehicle equipped with a turbo device and an intercooler. According to the present invention, the fluid duct device provided in an intake system of the vehicle includes: a base tubular body; a vortex forming member provided inside the base tubular body and configured to convert a flow of a passing fluid into a vortex flow; an outer tubular body fixed to the outside of the base tubular body so as to form a flow path through which the fluid flows between the base tubular body and the outer tubular body; and a connection fixing member forming a space between the base tubular body and the outer tubular body and connecting and fixing the base tubular body and the outer tubular body.

Description

Fluid duct device for reduced airflow resistance for automobiles {FLUID DUCT DEVICE FOR VEHICLE CAPABLE OF REDUCING AIR FLOW RESISTANCE}

The present invention relates to a fluid duct device for reducing airflow resistance for automobiles, and more particularly, to change the flow of fluid in a vehicle into a combination of vortex and straight airflow, and at the same time significantly reduce airflow resistance to achieve high-speed airflow Airflow resistance reduction type fluid duct for automobiles, which can be formed to be sucked into the engine of the automobile to completely burn the automobile fuel to increase the fuel efficiency, and to provide a greater effect, especially in automobiles equipped with a turbo device and an intercooler It's about the device.

As a major means of transportation, automobiles are becoming indispensable along with changes in life. These automobiles are classified into various types according to the driving method, engine (power source), and other uses of the vehicle, and the types are also very diverse. Among them, if automobiles are classified according to engines, they can be broadly classified into three types: internal combustion engine automobiles, electric automobiles, and steam automobiles. Among them, internal combustion engine vehicles can be divided into gasoline, diesel, LP gas, gas turbine, and jet engine.

Such an automobile is not a single mechanical structure, but an aggregation of science and technology in which each component is organically combined.

In general, a vehicle consists of various driving devices such as an engine, suspension, body frame, and steering system. In particular, the engine obtains power for driving the vehicle through suction, compression, expansion (explosion), and exhaust stroke of the supplied fuel. do. Among them, the air intake system of the automobile is a part responsible for the intake of the mixture (mixed gas) delivered into the cylinder for the continuous operation of the automobile engine.

In general, the intake system of automobiles is composed of an air cleaner that removes dust in the air sucked into a cylinder, and an intake duct including an intake manifold that distributes a mixture to the cylinder. It is an important part related to the complete combustion of

However, the conventional automobile intake system has the following problems.

As described above, the intake system of a vehicle is a part responsible for intake of air necessary for combustion of fuel, and the conventional intake apparatus does not efficiently inhale the air, and thus generates a large amount of soot, thereby polluting the environment and air. There is a problem that causes

The soot emitted from automobiles includes landfill abnormal substances (hereinafter referred to as 'PPM'), carbon, nitrogen compounds, graphite, and the like. Looking at PM among these soot, PM is a hazardous substance closely related to diesel engine among automobile engines, and includes graphite, SOF, sulfate, and the like. Graphite is called diesel smog, and it is the soot generated from the injection nozzle of a vehicle when a large amount of vehicle fuel is started. SOF is mainly generated after engine oil enters the cylinder and burns. It is soot produced by sulfuric acid.

In addition, carbon (carbon) is a carbon material and is discharged after combustion at a self-cleaning temperature of about 800° C. and remains in the engine of a vehicle. When such carbon is removed by a chemical or physical method, there is a problem in causing engine loss, and this carbon is also a material generated due to incomplete combustion of fuel. In addition, nitrogen compounds and graphite are soot that causes acid rain and adversely affects respiratory diseases of the human body.

Conventional automobiles have low fuel combustion efficiency, which is also a problem related to incomplete combustion. Low combustion efficiency reduces fuel efficiency of the vehicle and increases the amount of fuel consumed relatively. In general, pure substances have high ignitability and produce less soot during combustion.

Therefore, there is a problem in that the amount and condition of the intake air must be improved because the fuel of automobiles is easier to generate soot than pure substances.

Accordingly, the applicant of the present invention has applied for and registered in Republic of Korea Patent Publication No. 10-1365892 under the title of "Intake duct device for improving intake efficiency of intake system for vehicles".

The present invention has invented a fluid duct device capable of remarkably reducing airflow resistance compared to a previously registered intake duct device, thereby improving intake efficiency and thus exhaust efficiency.

Republic of Korea Patent Publication No. 10-1365892 (2014.02.21. Announcement) Korean Patent Publication No. 10-2020-0058719 (published on May 28, 2020)

Therefore, in order to solve the above-mentioned problems of the prior art, the fluid flow is changed to a combination of eddy current and straight air flow in the vehicle, and at the same time, the air flow resistance is significantly reduced to form a high-speed air flow to be sucked into the engine of the vehicle. An object of the present invention is to provide a fluid duct device for reducing airflow resistance for automobiles, which increases fuel efficiency by completely burning the fuel of the automobile, and can provide a greater effect, particularly in automobiles equipped with a turbo device and an intercooler.

The problems to be solved of the present invention are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

According to one aspect of the present invention for achieving the above objects and other features of the present invention, there is provided a fluid duct device provided in an intake system of a vehicle, comprising: a base tubular body; a vortex forming member provided in the base tubular body and configured to convert a flow of a passing fluid into a vortex flow; an outer tubular body fixed to the outside of the base tubular body to form a flow path through which a fluid flows between the base tubular body; and a connection fixing member for connecting and fixing the connection while forming a space between the base tubular body and the outer tubular body.

In the present invention, the inner edge of the base tubular body may be provided with a sub-vortex-forming member that is formed to protrude so as not to overlap the vortex-forming member when viewed in the fluid flow direction.

In the present invention, the vortex forming member is made of a plate-shaped first twisted portion and a second twisted portion twisted at a predetermined angle from one end to the other, the linear end of the first twisted portion and a second twisted portion continuous thereto The linear stages may be configured to cross each other.

In the present invention, the outer tubular body is formed of a venturi tube, and the connection fixing member may include an annular ring portion and a fixing protrusion formed with a gap in the circumferential direction on the inner periphery of the annular ring portion.

In the present invention, the annular ring portion may be provided with one or more air through-holes formed to penetrate in the fluid flow direction.

In the present invention, the fixing protrusion is formed as a protrusion of a triangular cross-section when viewed from the fluid flow direction, and in the protrusion formed in the triangular cross-section, the triangular slope is formed as a twisted face while going in the fluid flow direction. The fluid passing through the fixing protrusion may be made to form a vortex flow.

In the present invention, the base tubular body may have a plurality of air flow holes formed therein, and the outer tubular body may have a diameter of a central portion smaller than a diameter of both ends.

According to the airflow resistance reduction type fluid duct device for automobiles according to the present invention, the following effects are provided.

First, the present invention converts the flow of fluid into a combination of vortex and straight air flow in the vehicle through the coupling between the components and the structural features of the components, and at the same time significantly reduces the airflow resistance to form a high-speed airflow of the vehicle. There is an effect of increasing the fuel efficiency by completely burning the fuel of the vehicle by allowing it to be sucked into the engine.

Second, the present invention not only reduces the airflow resistance at the inlet and/or outlet of the fluid, but also reduces the airflow resistance by increasing the amount of air by implementing a multi-channel structure to completely burn the fuel of the vehicle to increase the fuel efficiency. Accordingly, by improving the efficiency of the intake system, the exhaust efficiency in the exhaust system is also increased, and there is an effect of preventing or minimizing the generation of soot.

Third, the present invention is applied to a vehicle having an intercooler and a turbo device for improving the efficiency of an intake system, thereby further increasing fuel efficiency.

Fourth, the present invention has the effect of improving the instantaneous acceleration by reducing the turbo lag phenomenon.

Effects of the present invention are not limited to those mentioned above, and other solutions not mentioned will be clearly understood by those skilled in the art from the following description.

1 is a perspective view showing an airflow resistance reduction type fluid duct device for a vehicle according to the present invention.
2 is an exploded perspective view showing an airflow resistance reduction type fluid duct device for a vehicle according to the present invention.
Figure 3 is a front view of the airflow resistance reduction type fluid duct device for a vehicle in accordance with the present invention viewed from the fluid inflow direction.
It is a front view which shows 1st Embodiment of the connection fixing member contained in the airflow resistance reduction type fluid duct apparatus for automobiles which concerns on this invention.
It is a front view which shows 2nd Embodiment of the connection fixing member contained in the airflow resistance reduction type fluid duct apparatus for automobiles which concerns on this invention.
It is a front view which shows 3rd Embodiment of the connection fixing member contained in the airflow resistance reduction type fluid duct apparatus for automobiles which concerns on this invention.
7 is a view showing a modified example of the airflow resistance reduction type fluid duct device for automobiles according to the present invention.
8 is a view showing a partial configuration in another modified example of the airflow resistance reduction type fluid duct device for a vehicle according to the present invention.
9 is a plan view showing modified examples of the base tubular body included in the airflow resistance reduction type fluid duct device for a vehicle according to the present invention.
10 is an exploded perspective view illustrating a case in which an outer tubular body of another type is included in the airflow resistance reduction type fluid duct device for a vehicle according to the present invention.
It is a figure which shows embodiment which installed the airflow resistance reduction type fluid duct device for automobiles which concerns on this invention in the automobile intake system.

Additional objects, features and advantages of the present invention may be more clearly understood from the following detailed description and accompanying drawings.

Prior to the detailed description of the present invention, the present invention can make various changes and can have various embodiments, and the examples described below and shown in the drawings are not intended to limit the present invention to specific embodiments. No, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

When a component is referred to as being “connected” or “connected” to another component, it may be directly connected or connected to the other component, but it is understood that other components may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

The terms used herein are used only to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present specification, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It is to be understood that this does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

In addition, terms such as "...unit", "...unit", "...module", etc. described in the specification mean a unit that processes at least one function or operation, which includes hardware or software or hardware and It can be implemented by a combination of software.

In addition, in the description with reference to the accompanying drawings, the same components are assigned the same reference numerals regardless of the reference numerals, and the overlapping description thereof will be omitted. In describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

Hereinafter, an airflow resistance reduction type fluid duct device for a vehicle according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view showing an airflow resistance reduction type fluid duct device for a vehicle according to the present invention, FIG. 2 is an exploded perspective view showing an airflow resistance reduction type fluid duct device for a vehicle according to the present invention, and FIG. 3 is the present invention It is a front view of a fluid duct device for reducing airflow resistance for automobiles according to the flow inflow direction. 4 is a front view showing a first embodiment of a connection fixing member included in the airflow resistance reduction type fluid duct device for a vehicle according to the present invention, and FIG. 5 is included in the airflow resistance reduction type fluid duct device for a vehicle according to the present invention It is a front view which shows 2nd Embodiment of the connection fixing member which becomes used, and FIG. 6 is a front view which shows 3rd Embodiment of the connection fixing member contained in the airflow resistance reduction type fluid duct apparatus for automobiles which concerns on this invention.

An airflow resistance reduction type fluid duct device for a vehicle according to the present invention is a fluid duct device installed in an intake system of a vehicle, and as shown in FIGS. 1 to 6 , largely includes a base tubular body 100; vortex forming member 200; outer tubular body 300; and a connection fixing member 400 .

Specifically, the airflow resistance reduction type fluid duct device for a vehicle according to the present invention is a fluid duct device installed in an intake system of a vehicle, and as shown in FIGS. 1 to 6 , a cylindrical base tubular body having a predetermined diameter (100); a vortex forming member 200 provided in the base tubular body 100 and configured to convert a flow of a passing fluid into a vortex flow; an outer tubular body 300 fixed to the outside of the base tubular body 100 via the following connection fixing member 400 to form a space so that a fluid flows between the base tubular body 100; and a connection fixing member 400 provided to connect and fix the outer tubular body 300 to the outside of the base tubular body 100 while forming a space between the base tubular body 100 and the outer tubular body 300; includes

The base tubular body 100 is formed in a cylindrical shape having a predetermined diameter and is configured to be provided with a vortex forming member 200 described in detail below therein.

Here, the base tubular body 100 may be formed with a sub-vortex-forming member (not shown) protruding from a portion where the vortex-forming member 300 is not provided. In other words, the sub vortex-forming member is formed to protrude so as not to overlap the vortex-forming member when viewed from the inner edge of the base tubular body 100 in the fluid flow direction.

The sub-vortex-forming member is formed of protruding pieces extending in the longitudinal direction and twisted to form a vortex in the same direction as the vortex-forming member 200, and the protruding pieces are formed at intervals in the circumferential direction.

Subsequently, the vortex forming member 200 is configured to convert the flow of the fluid passing through the interior of the base tubular body 100 into an eddy flow.

The vortex forming member 200 is composed of two or more plate-shaped twisted parts 210 and 220 twisted at a predetermined angle from one end to the other, and the linear end of the upstream twisted part (first twisted part) 210 and The linear ends of the downstream twisted part (second twisted part) 220 that are continuous thereto are formed in a relationship that intersects with each other.

In the plate-shaped twisted parts 210 and 220 of the vortex forming member 200, the intersection angle between the linear end of the upstream twisted part 210 and the linear end of the downstream twisted part 120 is greater than 0° and less than 180° It may be in the range of, preferably 85 ° to 95 ° is preferred, particularly preferably 90 ° is preferred.

In addition, in the plate-shaped twisted parts 210 and 220 constituting the vortex forming member 200, the twist angle twisted at a predetermined angle from one end to the other end may be in the range of 45° or more and less than 180°, preferably 85 It is preferably ° to 95 °, particularly preferably 90 °.

In addition, the end of the plate-shaped twisted part 120 located on the rearmost side among the plate-shaped twisted parts 210 and 220 of the vortex-forming member 200 includes an airflow converting means for converting the vortex-shaped flow into a linear flow. . The air flow conversion means is a means for converting the flow of the fluid in the form of a vortex by the upstream and downstream twisting parts 210 and 220 so as to flow in a straight line at the most downstream side.

The airflow converting means 200 is formed of a plate-shaped member extending linearly from the linear end of the downstream twist portion 220 .

The plate-shaped member may be integrally formed when the downstream twisted part 220 is manufactured, or may be separately formed and configured to be installed at the downstream end of the downstream twisted part 220 . A back pressure through hole is formed in the plate-shaped member, and the pressure at the upper and lower sides thereof can be equalized through the back pressure through hole 210 .

When the rotation of the fluid flow at the distal end of the downstream twist part 220 ends, the air flow converting means formed in this way distributes the fluid pressure received toward the inner wall of the pipe toward the straight plate-shaped member to change the direction of the air flow to the straight direction.

Accordingly, by dispersing the exhaust pressure acting toward the inner wall of the pipe at the distal end of the vortex forming member 200, the vortex forming member 200 is prevented from falling from the base tubular body 100, and at the same time, the pipe vibration and noise are reduced and Allow the fluid to drain smoothly.

Subsequently, the outer tubular body 300 is fixed to the outside of the base tubular body 100 via the following connection fixing member 400 to form a space so that the fluid flows between the base tubular body 100 and the base tubular body 100 . it is composed

The outer tubular body 300 is preferably formed as a venturi tube so that the fluid flow at the center side flows faster than the fluid flow at the front end and the rear end (based on the fluid flow).

Next, the connection fixing member 400 connects and fixes the outer tubular body 300 to the outside of the base tubular body 100 while forming a space between the base tubular body 100 and the outer tubular body 300 . is composed of

The connection fixing member 400 includes an annular ring portion 410 and a fixing protrusion 420 formed with a gap in the circumferential direction on the inner periphery of the annular ring portion 410 .

One or more air through-holes 411 are formed in the annular ring part 410 in the fluid flow direction as shown in FIGS. 4 to 6 , respectively.

The air through hole 411 is preferably formed on the side where the fixing protrusion 420 is formed.

The air through hole 411 is made of not only a circle including an oval, but also a polygon such as a quadrangle, and is preferably formed in a circular shape.

As described above, the air through hole 411 is formed in the connection fixing member 400 to reduce the airflow resistance of the fluid flowing into the space between the base tubular body 100 and the outer tubular body 300 .

In addition, as shown in FIG. 6 , the fixing protrusion 420 is formed as a protrusion having a triangular cross-section when viewed from the fluid flow direction. Here, in the protrusion formed in the triangular cross-section, the oblique surface of the triangle is formed to have a twisted surface while going in the longitudinal direction (ie, the fluid flow direction) and passes through the fixing protrusion 420 , that is, the fixing protrusion 420 . ) so that the fluid passing through it forms a vortex flow.

The twisted surface of the fixing protrusion 420 is twisted in the same direction as the twist direction of the vortex forming member 200 provided in the base tubular body 100, and is the same as the vortex direction formed by the vortex forming member 200 It is made to form a vortex in the direction.

As such, the fluid passing through the inside of the base tubular body 100 passes while forming a vortex by the vortex forming member 200, and at the same time, the base tubular body ( The fluid passing through the space between 100) and the outer tubular body 300 also passes while forming a vortex, and all the fluids passing through the two passages flow rapidly, especially the outer tubular body 300 formed in the form of a venturi tube. ) to form a faster airflow.

On the other hand, Figure 7 is a view showing a modified example of the airflow resistance reduction type fluid duct device for automobiles according to the present invention.

A modified example of the airflow resistance reduction type fluid duct device for automobiles according to the present invention is, as shown in FIG. 7 , the first base tubular body 110 and the second base tubular body each having the vortex forming member 200 described above. It is divided into 120 and the first base tubular body 110 and the second base tubular body 120 are fixed to the inner both ends of the outer tubular body 300 via the connection fixing members 400, respectively. composed to be

Here, the first base tubular body 110 and the second base tubular body 120 may be configured to have an upstream twisted part 210 and a downstream twisted part 220 therein, respectively.

In addition, the diameter of the first base tubular body 110 and the second base tubular body 120 may be the same or may be configured to have different diameters.

8 is a view showing a partial configuration in another modified example of the airflow resistance reduction type fluid duct device for automobiles according to the present invention.

As another modified example of the airflow resistance reduction type fluid duct device for automobiles according to the present invention, as shown in FIG. 8 , the first base tubular body 110 and the second base tubular body 120 are not linear, but a predetermined angle It may be configured in a form combined with and.

In this case, the outer tubular body 300 is provided at the outer edge of each of the base tubular bodies 110 and 120 via the connection fixing member 400 as a medium.

This other modification can not only be applied to the airflow path of the intake system that can change direction, but also change the direction of the vortex flow at a predetermined angle in the linear intake system to proceed.

Next, FIG. 9 is a plan view showing modified examples of the base tubular body included in the airflow resistance reduction type fluid duct device for a vehicle according to the present invention.

In the airflow resistance reduction type fluid duct device for automobiles according to the present invention, the base tubular body 100, 110, 120 is, as shown in FIG. 9, a plurality of airflow flow holes 101 are formed, in FIG. ), it has a gap in the airflow direction and can be formed over the entire circumference of its base tubular body, which is relatively larger in the airflow direction than that of FIG. It has a gap and can be formed only in a few parts of the circumference of the base tubular body.

The airflow hole 101 may be formed as a circular hole as shown in FIG. 9A, and in the longitudinal direction of the base tubular body 100, 110, 120 as shown in FIG. 9B. It may be formed in the form of a slit inclined with respect to or in a long hole.

In FIG. 9 , a linear plate 230 is further extended from one end of the vortex forming member 200 , and a through hole 231 is formed in the linear plate 230 .

10 is an exploded perspective view illustrating a case in which an outer tubular body of another type is included in the airflow resistance reduction type fluid duct device for a vehicle according to the present invention. can be

In other words, the outer tubular body 300 may be formed so that the diameter of the central portion is relatively smaller than the diameter of both ends.

When the outer tubular body 300 is formed as described above, the air flow at the point in time passing through the central portion can be made to flow relatively quickly according to the Bernoulli principle.

11 is a view showing an embodiment in which an airflow resistance reduction type fluid duct device for automobiles according to the present invention is installed in an automobile intake system, and is a view showing a case in which the embodiment of FIG. 10 is applied.

According to the airflow resistance reduction type fluid duct device for automobiles according to the present invention as described above, the flow of fluid in the vehicle is changed to a combination of vortex and straight air flow through the coupling between the components and the structural features of the components. At the same time, the airflow resistance is significantly reduced to form a high-speed airflow to be sucked into the engine of the vehicle, so that the fuel of the vehicle is completely burned to increase the fuel efficiency, and the airflow resistance at the inlet and/or outlet of the fluid is reduced. It not only reduces the airflow resistance by increasing the amount of air by implementing a multi-channel structure, but also increases the fuel efficiency by completely burning the fuel of the vehicle by further reducing the airflow resistance. There is an advantage in that it is possible to prevent or minimize the generation of soot.

In addition, according to the present invention, it is applied to a vehicle having an intercooler and a turbo device for improving the efficiency of the intake system, so that fuel efficiency can be further increased, and there is an advantage of improving the instantaneous acceleration by reducing the turbo lag phenomenon.

The embodiments described in this specification and the accompanying drawings are merely illustrative of some of the technical ideas included in the present invention. Therefore, since the embodiments disclosed in the present specification are for explanation rather than limiting the technical spirit of the present invention, it is obvious that the scope of the technical spirit of the present invention is not limited by these embodiments. Modifications and specific embodiments that can be easily inferred by those skilled in the art within the scope of the technical spirit included in the specification and drawings of the present invention should be interpreted as being included in the scope of the present invention.

100: base tubular body
101: air flow hole
110: first base tubular body
120: second base tubular body
200: vortex forming member
210: upstream twist part (first twist part)
220: downstream twisted part (second twisted part)
300: outer tubular body
400: connection fixing member
410: annular ring portion
411: through hole
420: fixed protrusion

Claims (7)

As a fluid duct device provided in the intake system of a vehicle,
base tubular body;
a vortex forming member provided in the base tubular body and configured to convert a flow of a passing fluid into a vortex flow;
an outer tubular body fixed to the outside of the base tubular body to form a flow path through which a fluid flows between the base tubular body; and
and a connection fixing member for connecting and fixing while forming a space between the base tubular body and the outer tubular body.
Airflow resistance reduction type fluid duct device for automobiles.
According to claim 1,
In the inner edge of the base tubular body, when viewed in the fluid flow direction, it characterized in that it is provided with a sub-vortex-forming member is formed to protrude so as not to overlap the vortex-forming member.
Airflow resistance reduction type fluid duct device for automobiles.
3. The method of claim 1 or 2,
The vortex forming member includes a plate-shaped first twisted portion and a second twisted portion twisted at a predetermined angle from one end to the other end, wherein the linear end of the first twisted portion and the linear end of the second twisted portion successive thereto cross each other characterized in that it is composed
Airflow resistance reduction type fluid duct device for automobiles.
According to claim 1,
The outer tubular body is formed of a venturi tube,
The connection fixing member is characterized in that it comprises an annular ring portion, and a fixing protrusion formed with a gap in the circumferential direction on the inner edge of the annular ring portion.
Airflow resistance reduction type fluid duct device for automobiles.
5. The method of claim 4,
The annular ring portion is characterized in that it has one or more air through-holes formed to penetrate in the fluid flow direction.
Airflow resistance reduction type fluid duct device for automobiles.
6. The method according to claim 4 or 5,
The fixing protrusion is formed as a protrusion of a triangular cross-section when viewed from the fluid flow direction,
In the protrusion formed in the triangular cross-section, the triangular slope is formed as a twisted face while going in the fluid flow direction so that the fluid passing through the fixing protrusion forms a vortex flow.
Airflow resistance reduction type fluid duct device for automobiles.
According to claim 1,
The base tubular body is formed with a plurality of airflow flow holes,
The outer tubular body is characterized in that the diameter of the central portion is formed to be relatively smaller than the diameter of the both ends.
Airflow resistance reduction type fluid duct device for automobiles.

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