JP2001050215A - Karman's vortex reducing body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To expand an application range of a Karman's vortex reducing body and to enhance a degree of freedom at an application portion by providing the reducing body freely attachable/detachable to/from a surface of an object in contact with fluid and made of a base material provided with many projecting parts, recessed parts, projecting lines or recessed grooves on a surface. SOLUTION: In this Karman's vortex reducing body 1, a synthetic resin sheet 10 is made as a base material, a semi-spherical synthetic resin projecting part 2 is molded integrally with the surface, and an adhesive layer 11 and a peeling sheet 12 are adhered to a rear face of the sheet 10. When the body 1 is used, the reducing body 1 is cut according to an adhering object portion, and the peeling sheet 12 is peeled and adhered to a surface of an automobile. At the time of a traveling, air turbulence flowing from an advancing direction collides against the projecting part 2 and is collapsed, regularity of turbulence is lost, each vortex itself is made small, a Karman's vortex is prevented from being formed, and wind noise and air resistance are reduced. By the constitution, a user himself can freely select a mounting portion and a range of the reducing body 1 and the projecting part 2, an application range is expanded and a degree of freedom of an application portion is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Karman vortex reducer that suppresses the generation of Karman vortices that cause wind noise by providing a large number of convex portions and the like.

[0002]

2. Description of the Related Art For example, in an automobile moving at high speed in the air, the air relatively moves along the automobile surface from the front to the rear of the automobile. At this time, separation of the air flow occurs at the boundary between the windshield and the roof, at the edge of the rear end, the spoiler, or the like, or at the gap between the door mirror and the door, and turbulence occurs. Depending on the speed of the car, this turbulence can form large vortices (Karman vortices) with regularity, which not only generates wind noise but also increases air resistance.

Particularly, in recent years, a spoiler for accommodating a tail lamp or the like has become thicker and has a constant front and rear width, so that the tail end becomes an edge part which is inevitably raised, and the occurrence of the Karman vortex has been inevitable. Therefore, regarding this spoiler, a technique aimed at reducing wind noise (Japanese Patent Laid-Open No. 09-002339, Japanese Patent Laid-Open No. 10-045046)
Is disclosed. In any case, a step is provided in the middle of the spoiler to generate a small vortex in advance, thereby preventing the occurrence of Karman vortex which also causes wind noise.

[0004]

The above technique for providing a step on a spoiler is a subtle and excellent technique for suppressing the occurrence of Karman vortices. However, molding a step integrated with a spoiler in advance is difficult to deal with except for the manufacturer, and also has a problem that the design is not as desired by the car owner.

[0005] Suppressing the generation of Karman vortices and suppressing wind noise by randomly generating new small turbulence on the windward side of the site where Karman vortices are generated suppresses an increase in air resistance due to Karman vortices. It also leads to things. Therefore, it is preferable that this technical idea can be widely applied to noise reduction and fluid resistance reduction based on fluid separation, and it is preferable that the owner of an automobile or the like can freely form an uneven portion or the like. Therefore, in order to expand the range of application and to increase the degree of freedom of the application site, a detachable member was studied.

[0006]

Means for Solving the Problems The thing developed as a result of the study is (1) a base material which is detachable on the surface of the object in contact with the fluid and has a large number of projections, depressions, ridges or grooves on the surface. It is a Karman vortex reducer. Each of the convex portions, concave portions, convex stripes or concave grooves has a function of dispersing a fluid to be separated from an object into small vortices in advance so as not to form a large vortex (Kalman vortex). In the case where the surface of the object to which the projections or the like are to be attached is inconvenient for attaching the base material, (2)
It is convenient to use a Karman vortex reducer composed of a convex portion, a concave portion, a convex ridge, or a concave groove which is detachable from the surface of an object in contact with the fluid. This is because the projections and the like are independent for each one. Even when the curved surface of the object surface is extremely changed, it is possible to easily mount the object while arranging the convex portions and the like along the curved surface.

[0007] The convex or concave portion is usually the diameter of a car.
Based on a hemispherical shape of 0.5 to 20 mm, various polygonal shapes, ellipsoids, and the like are also formed with substantially the same size. When the object to be attached is scaled up or down with respect to the ordinary vehicle, the size of the convex or concave portion is enlarged or reduced in accordance with the scale. Only the convex portions, only the concave portions, or the mixture of both are free. The ridge or groove has a width or height of 0.5
It may be in the range of 〜20 mm, preferably 1.0-15 mm, and may be arranged continuously or intermittently on the surface of the substrate. The extending direction of the ridge or the groove is preferably a direction perpendicular to the main flow direction of the fluid, but the actual flow of the fluid is irregular, so if it is provided to intersect with the flow direction in which the fluid most likely flows. Good. Only the ridges, only the grooves, or the mixture of the two are free, and a combination with the protrusions or the recesses is also possible.

[0008] The fluid mentioned here is mainly air and water, but refers to a fluid that moves relatively to an object. The object generally means an object that moves in a fluid, and refers to a car or a ship on the water in the air, but also includes a building or the like exposed to the wind. That is, in the case of a building, the object stops and the fluid collides with the object with a flow. The present invention is applicable as long as there is a relative speed difference between the fluid and the object.

Specific examples of the Karman vortex reducer include: (a) a substrate whose base material is a flexible sheet;
(Kanman vortex reducer (sheet type) having a layer (including adhesive)), (b) The base material is a rigid plate material, which can be arbitrarily set by mechanical means such as bolting and riveting to the object to be detached. There is a Karman vortex reducer (board type) that can be attached to and detached from. In the sheet type, a tape, a sticker or a sticker is attached to a curved surface, and a convex portion or the like can be arranged at an arbitrary position. It is suitable when an individual sticks it to the blade of a car or electric fan. The board type can firmly attach the base material to the object when the attachment strength is required, and can prevent unexpected peeling. The board type is suitable for, for example, a case where projections and the like are arranged on the outer wall of a ship or a building.

[0010]

Embodiments of the present invention will be described below. FIG. 1 is a side view of an automobile on which various sheet-type Karman vortex reducers 1 are attached, FIG. 2 is an overall perspective view of a sheet-type Karman vortex reducer 1 in which hemispherical convex portions 2 are arranged, and FIG. Hemispheric convex part 2 in vortex reducer 1
FIG. 4 is a partial side view for explaining the disturbing action of the air 3 by the Karman vortex reducer 1. This example shows a fender cover 4, a side under cover 5, a front glass end 6 (front edge of a ceiling surface), an inner surface of a door mirror 7, a side visor 43, a lower surface of a rear spoiler 8, and a side end 9 (a rear edge of a side surface) of a one-box-like ordinary car. This is an example in which an individual sheet type Karman vortex reducer 1 is adhered to each. The Karman vortex reducer other than the illustrated ones and the Karman vortex reducer can be freely adhered to portions other than those illustrated.

As shown in FIG. 1, the Karman vortex reducer 1 of the present invention is attached to a portion where air separation may occur in the traveling direction. Although the shape and size of the Karman vortex reducer 1 attached to each part are different, each is a sheet type as shown in FIG. That is, using a flexible synthetic resin sheet 10 as a base material, a hemispherical convex portion 2 of synthetic resin is integrally formed on the surface of the sheet 10, and an adhesive layer 11 and a release sheet 12 are attached on the back surface of the sheet. I have. In use, first, Karman vortex reducer 1
Is cut out in accordance with the portion to be attached, the release sheet 12 on the back surface of the sheet is peeled off, and the sheet is attached to the surface of the automobile.

As a representative, the Karman vortex reducer 1 stuck to the fender cover 4 (see FIG. 1) will be described. As shown in FIG. 2 and FIG.
It has an appearance in which hemispherical projections 2 are arranged at regular intervals. When such a Karman vortex reducer 1 is attached to the surface of an automobile,
As can be seen in FIG.
The turbulence of the turbulent flow again hits each convex portion 2 and breaks, thereby impairing the regularity of the turbulent flow, making each vortex itself small, and preventing the formation of Karman vortices. In this way, wind noise is suppressed, and air resistance generated by the generation of Karman vortices is reduced. For example, in the case of an automobile, this leads to effects such as improved fuel efficiency.

According to the present invention, a convex portion or the like is disposed at a portion where fluid separation occurs to prevent turbulent flow from developing into a Karman vortex, regardless of the shape of the convex portion. It may be a strip or a groove. 5 to 16 are perspective views corresponding to FIG. 3 of the representative Karman vortex reducer 1, FIG. 5 is an arrangement of truncated cone projections 13, and FIG. 6 is an arrangement of quadrangular pyramids (diamond cone) projections 14. 7 is an array of semi-ellipsoidal convex portions 15, FIG. 8 is an array of triangular pyramid concave portions 16, FIG. 9 is an array of hemispherical boring partitioning convex portions 17, FIG. 10 is an array of triangular fragment-causing convex portions 18, and FIG. An array of deformed quadrangular pyramids (diamond pyramids) convex portions 19, FIG. 12 shows an array of triangular cross-sectional ridges 20, FIG. 13 shows an array of trapezoidal cross-sectional ridges 21, and FIG.
FIG. 15 shows the arrangement of the combination of the ridges 23 and the concave grooves 24, and FIG. 16 shows the arrangement of the ridges 25.

5 and 6, the truncated cone projection 13 and the quadrangular pyramid projection.
Numeral 14 is omnidirectional as in the case of the hemispherical convex portion 2 of FIG. 3 and does not select a place where the Karman vortex reducer 1 is attached. In FIG. 7, since the semiellipsoidal projection 15 is elongated in one direction, the extending direction of the semiellipsoidal projection 15 is the main direction F of the flow of the air 3 (open arrows in the figure).
The Karman vortex reducer 1 may be stuck so as to match the above. Although the triangular pyramid concave portion 16 in FIG. 8 has the same directionality as in FIG. 7, none of the directions is absolute, and from the viewpoint of suppressing the occurrence of Karman vortices, even if air flows from any direction. No problem. As a device that actively adds directionality, there is the Karman vortex reducer 1 shown in FIGS. 9 and 10. In both cases, the effect of reducing the Karman vortex in the main direction F of the air flow (open arrow in the figure) is the best. FIG.
Is an example of a convex shape and an arrangement in which the deformed quadrangular pyramid convex portions 19 are more densely arranged. In the above example (FIG. 1), the convex quadrangular pyramid convex portions 19 are arranged on the side under cover 5 in the traveling direction. The protrusions or recesses are based on a regular arrangement as exemplified above,
It may be irregular.

[0015] Instead of the convex portion or the concave portion, a convex ridge or a concave groove may be used. Basically, an example of a continuous arrangement of triangular cross-sectional ridges 20 as shown in FIG. 12, an example of an intermittent arrangement of trapezoidal cross-sectional ridges 21 as shown in FIG. 13, and FIG. An example of an intermittent arrangement of the triangular cross-sectional grooves 22 can be shown. The ridges and the grooves have a paired relationship, and the formation of the ridges can be regarded as the formation of the grooves. For example, FIG.
As shown in FIG. 5, the semi-circular cross-sectional ridges 23 having a radius ratio of 2: 1 and the semi-circular cross-sectional grooves 24 may be alternately arranged. In addition,
As seen in Fig. 16, wind-like ridges 25 with enhanced design
May be arranged. Even in this ridge or groove,
In addition to the regular arrangement as illustrated, the arrangement may be irregular. Although illustration is omitted, a combination of a convex portion, a concave portion, a convex ridge or a concave groove may be used.

FIGS. 17 to 22 are perspective views (FIGS. 17, 21 and 22), side views (FIGS. 18 and 20) or front views (FIG. 19) showing an application example of the present invention. Is an example of application to a tanker 26, FIG. 18 is an example of application to a helmet 27, FIG. 19 is an example of application to a fan 28, FIG.
20 is an example of application to a construction machine 29, FIG. 21 is an example of application to a building 30,
FIG. 22 shows an example of application to the bridge 31. The present invention is basically applied to an object moving in a fluid, the above-described automobile, and the like. In addition to the automobile, as shown in FIG. 17, the attachment of the Karman vortex reducer 1 to the bow portion 32 or the stern portion 41 of the tanker 26 can be exemplified. In this case, the Karman vortex reducer 1 is made of a board type made of a steel plate or the like and is fixed by bolts so as not to fall off during traveling. A vortex was most likely to be generated at the bow portion 32 of the ship, and this vortex was a resistance. By applying the present invention, the vortex is reduced, and it is possible to improve the relative structural strength of the ship and improve fuel efficiency. In addition to the examples, the present invention can be applied to trains and the like.

The object moving in the fluid is not limited to transportation. For example, a motorcycle driver's helmet 27 also moves at high speed in the air. In particular, the visor mounting portion 33 was inevitably formed with a seam, which easily caused wind noise. Therefore, as shown in FIG.
If the Karman vortex reducer (sheet type) 1 is attached to the lower edge 33 and the rear side 42 of the helmet 27 and the helmet 27, harsh wind noise can be reduced. Since the helmet 27 was attached to the head and the wind noise of the visor attachment portion 33 was directly audible to the ears, a great deal of quietness was obtained as a bodily sensation.

In terms of the generation of wind noise, the electric fan 28
The sound of the wing 35 is also harsh. Therefore, as shown in FIG. 19, when the Karman vortex reducer (sheet type) 1 is attached to the edge portion 36 of each blade 35, the wind noise is reduced. If the Karman vortex reducer 1 is colored, the fan 28 can be produced in design, and there is an advantage that a person who is far away can be informed of the rotation of the blade 35.

Wind noise can occur even when the object is stationary with respect to the fluid. For this reason, the Karman vortex reducer of the present invention can be applied to an object whose position is fixed opposite to wind or flowing water. For example, as shown in FIG. 20, a Karman vortex reducer (sheet type or board type) 1 is attached to a construction machine 29 having an arm 37 having a long overall length. The arm 37 opposed to the strong wind impairs the stability of the construction machine 29 due to the generation of Karman vortex. However, the problem can be solved by installing the Karman vortex reducer 1 of the present invention.

The Karman vortex reducer 1 of the present invention can be applied regardless of the size of the object. A building can be exemplified as an object opposed to the wind like the construction machine described above. Especially at the edge of high-rise buildings 30 or condominiums
At 38, a large vortex is generated, which not only generates a wind noise, but also disturbs the surrounding airflow, rarely blowing a gust of a building style. Therefore, as shown in FIG.
By attaching the Karman vortex reducer (angled board type) 1 to 38, the generation of such a large vortex can be suppressed. For application to such a large object, a board-type Karman vortex reducer made of a metal plate or a ceramic plate, or a Karman vortex reducer in which only convex portions and the like are individually attached and arranged are used. In particular, the ceramic plate is rich in weather resistance, and is suitable for application to the building 30 on the premise of long-term outdoor use.

An example in which the Karman vortex reducer 1 is applied to a pier 39 of a bridge 31 as a building fixed in position against water flow can be shown. In particular, the pier 39 of the bridge 31 bridged over the river 40 always hits the water flow from one direction, generates entrainment consisting of a large vortex on the other side, goes through the sediment at the bottom of the river, and in some cases tilts the pier 39 , Which can lead to collapse. Therefore, as shown in FIG. 22, the Karman vortex reducer 1 is attached to the side surface of the pier 39 to suppress the generation of the vortex, and to ensure the stability of the pier 39. A sheet-type or board-type Karman vortex reducer can be attached to the flat portion of the pier 39, but it is preferable to separately attach a convex portion or the like to the curved surface portion of the pier 39 by bolting. Each projection is preferably made of synthetic resin or ceramic from the viewpoint of rust prevention and strength.

[0022]

According to the present invention, the reduction or suppression of Karman vortices in various objects can be realized more easily than before. In addition, the Karman vortex reducer is detachable by the user irrespective of the sheet type or the board type. In particular, in the case of the sheet type, the user himself / herself can freely select an attachment site, a range, a convex portion, and the like. in this way,
The present invention is based on the point that the Karman vortex (or vortex that does not lead to the Karman vortex but increases wind noise and resistance) is appropriately reduced or suppressed according to the user's intention while expanding the range of application and increasing the degree of freedom of the application site. It has the greatest effect.

[Brief description of the drawings]

FIG. 1 is a side view of an automobile to which various sheet-type Karman vortex reducers are attached.

FIG. 2 is an overall perspective view of a sheet type Karman vortex reducer in which hemispherical convex portions are arranged.

FIG. 3 is a partial perspective view showing an arrangement of hemispherical protrusions in the Karman vortex reducer.

FIG. 4 is a partial side view illustrating the air turbulence effect of the Karman vortex reducer.

FIG. 5 is a diagram illustrating a Karman vortex reducer in which truncated cones are arranged.
It is an equivalent perspective view.

6 is a perspective view corresponding to FIG. 3 of a Karman vortex reducer in which quadrangular pyramids (diamond pyramids) convex portions are arranged.

FIG. 7 is a perspective view corresponding to FIG. 3 of a Karman vortex reducer in which semi-ellipsoidal convex portions are arranged.

FIG. 8 shows a Karman vortex reducer in which triangular pyramid concave portions are arranged.
It is an equivalent perspective view.

FIG. 9 is a perspective view corresponding to FIG. 3 of a Karman vortex reducer in which hemispherical boring screen projections are arranged.

10 is a perspective view corresponding to FIG. 3 of a Karman vortex reducer in which triangular fragments are raised and convex portions are arranged.

FIG. 11 is a perspective view corresponding to FIG. 3 of a Karman vortex reducer in which deformed quadrangular pyramids (diamond pyramids) convex portions are arranged.

FIG. 12 is a perspective view corresponding to FIG. 3 of a Karman vortex reducer in which ridges having a triangular cross section are arranged.

FIG. 13 is a perspective view corresponding to FIG. 3 of a Karman vortex reducer in which trapezoidal cross-sectional ridges are arranged.

FIG. 14 is a perspective view corresponding to FIG. 3 of a Karman vortex reducer in which triangular cross-section concave grooves are arranged.

FIG. 15 is a perspective view corresponding to FIG. 3 of a Karman vortex reducer in which convex and concave grooves having a semicircular cross section are arranged in combination.

[FIG. 16] FIG. 3 of the Karman vortex reducer in which wind-like ridges are arranged
It is an equivalent perspective view.

FIG. 17 is a perspective view showing an example of application to a tanker.

FIG. 18 is a side view showing an example of application to a helmet.

FIG. 19 is a front view showing an application example to a fan.

FIG. 20 is a side view showing an example of application to a construction machine.

FIG. 21 is a perspective view showing an example of application to a building.

FIG. 22 is a perspective view showing an application example to a bridge.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Karman vortex reducing body 2 Hemispheric convex part 10 Synthetic resin sheet 11 Adhesive layer 12 Release sheet F Main direction of fluid flow

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[Procedure amendment]

[Submission date] April 28, 2000 (200.4.2
8)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

Claims (4)

[Claims] 1. A Karman vortex reducer comprising a base material which is detachably attached to the surface of an object in contact with a fluid and has a large number of projections, depressions, ridges or grooves on the surface. 2. A Karman vortex reducer comprising a convex portion, a concave portion, a ridge or a groove which is detachable from the surface of an object in contact with a fluid. 3. The Karman vortex reducer according to claim 1, wherein the base material is a flexible sheet, and an adhesive layer is provided on the back surface of the sheet. 4. The Karman vortex reduction according to claim 1, wherein the base material is a rigid plate material, which can be arbitrarily attached to and detached from an object to be attached and detached by mechanical means such as bolting and riveting. body.