A chiral eccentric acoustic black hole structure

Abstract

The present invention discloses a chiral eccentric acoustic black hole structure, comprising: four acoustic black hole structures; the four acoustic black hole structures are arranged in a well shape; a cavity in the shape of a frustum of a cone with an open top is wrapped inside each of the acoustic black hole structures; a circular area at the bottom of the cavity is an eccentric platform; the center of the eccentric platform deviates from the center of the acoustic black hole structure. By arranging four acoustic black hole structures in a well shape, the present invention overcomes the dependence of the energy aggregation characteristic on the wave incident direction, and achieves the purpose of omnidirectional wave aggregation and wave rotation.

Description

Technical Field

[0001] The present invention relates to the technical field of wave energy concentration, and particularly to a chiral eccentric acoustic black hole structure. Background Art

[0002] In the prior art, a plurality of elliptical acoustic black holes (ABHs) are arranged in parallel. During the propagation of waves through each ABH, the waves will be further concentrated due to the gradient refractive index. That is to say, when the number of embedded ABHs increases from 1 to 3, the effect of wave energy concentration gradually enhances.

[0003] Therefore, by improving the cross-sectional form on the basis of the traditional acoustic black hole and arranging multiple ABHs, the wave concentration characteristics can be enhanced. However, it still has the drawback that the concentration characteristics depend on the incident direction of the incident wave. In the plate structure with multiple elliptical acoustic black holes arranged in parallel, when the incident direction of the incident wave is perpendicular to the long axis of the ellipse, effective energy concentration can be achieved. When the incident direction of the incident wave rotates by 90 degrees, that is, perpendicular to the short axis direction of the ellipse, the energy concentration effect cannot be achieved. Summary of the Invention

[0004] The object of the present invention is to provide a chiral eccentric acoustic black hole structure that can achieve wave concentration when the incident wave is incident at any angle.

[0005] To achieve the above object, the present invention provides the following solution:

[0006] A chiral eccentric acoustic black hole structure, comprising: four acoustic black hole structures;

[0007] The four acoustic black hole structures are placed in a well shape; a cavity in the shape of a frustum of a cone with an open top is wrapped inside each acoustic black hole structure; the circular area at the bottom of the cavity is an eccentric platform; the center of the eccentric platform deviates from the center of the acoustic black hole structure.

[0008] Optionally, between the center of the eccentric platform and the center of the acoustic black hole structure, the direction of the center deviation is a horizontal direction or a vertical direction.

[0009] Optionally, in the acoustic black hole structures placed in a well shape, if the direction of the center deviation of the acoustic black hole structure in the lower left corner is a horizontal direction, then the acoustic black hole structures placed in a well shape form a left-handed chiral eccentric acoustic black hole structure.

[0010] Optionally, in the acoustic black hole structures placed in a well shape, if the direction of the center deviation of the acoustic black hole structure in the lower left corner is a vertical direction, then the acoustic black hole structures placed in a well shape form a right-handed chiral eccentric acoustic black hole structure.

[0011] Optionally, a center deviation line segment is formed by connecting the center of the eccentric platform to the center of the acoustic black hole structure.

[0012] Optionally, the extension lines of the center deviation line segments of the four acoustic black hole structures are orthogonal to each other in pairs.

[0013] According to the specific embodiments provided by the present invention, the following technical effects are disclosed:

[0014] Through the arrangement of four eccentric acoustic black holes and the distribution characteristics of their eccentric distances, the present invention overcomes the dependence of the energy aggregation characteristics on the wave incident direction in the original acoustic black hole structure. Through the arrangement of multiple eccentric acoustic black holes, when incident waves enter from all around, the characteristics of omnidirectional wave aggregation and rotational propagation are ensured, achieving the purpose of omnidirectional wave aggregation and wave rotation. Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0016] Figure 1 This is the left-handed eccentric acoustic black hole structure of the chiral eccentric acoustic black hole structure of the present invention;

[0017] Figure 2 This is the right-handed eccentric acoustic black hole structure of the chiral eccentric acoustic black hole structure of the present invention. Detailed Embodiments

[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0019] The purpose of the present invention is to provide a chiral eccentric acoustic black hole structure. By arranging four acoustic black hole structures in a well-like pattern, the dependence of the energy aggregation characteristics on the wave incident direction is overcome, achieving the purpose of omnidirectional wave aggregation and wave rotation.

[0020] To make the above objects, features, and advantages of the present invention more clearly understandable, the present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0021] Such as Figure 1 - Figure 2As shown in the figure, the chiral eccentric acoustic black hole structure of the present invention includes: four acoustic black hole structures; the four acoustic black hole structures are placed in a well shape; each of the acoustic black hole structures is wrapped with a frustum-shaped cavity with an open top; the circular area at the bottom of the cavity is an eccentric platform; the center of the eccentric platform is offset from the center of the acoustic black hole structure.

[0022] The thickness change of a single acoustic black hole structure is shown in Equation (1):

[0023] h(r, θ) = ε(r - r1) m + h1, (r1 ≤ r ≤ r2(θ)) (1);

[0024] Where h(r, θ) is the thickness of the acoustic black hole structure; r is the distance from any point inside the cavity to the center of the circle; θ is the polar angle; h1 is the minimum thickness of the acoustic black hole structure; r1 is the radius of the eccentric platform; r2(θ) is the radius of the top of the cavity; ε is the radius coefficient; m is the power exponent.

[0025] And the radius r2(θ) of the top of the cavity is determined according to the following formula (2), and the radius coefficient ε is determined according to the following formula (3).

[0026]

[0027]

[0028] Where h2 is the maximum thickness of the uniform plate; e is the deviation distance between the center of the uniform plate and the center of the circular platform.

[0029] Connect the center of the eccentric platform and the center of the acoustic black hole structure as the center deviation line segment. Among the four center deviation line segments of the four acoustic black hole structures, a well distribution is formed, and the extension lines of the center deviation line segments of the four acoustic black hole structures are orthogonal to each other in pairs.

[0030] Between the center of the eccentric platform and the center of the acoustic black hole structure, the center deviation direction is horizontal or vertical. Depending on the different center deviation directions of the center deviation line segments, the four acoustic black hole structures can form two chiral forms, namely left-handed and right-handed.

[0031] If the center deviation direction of the acoustic black hole structure in the lower left corner of the well-placed acoustic black hole structures is horizontal, then the well-placed acoustic black hole structures form a left-handed chiral eccentric acoustic black hole structure, as Figure 1 shown.

[0032] If in the well - placed acoustic black hole structure, the deviation direction of the center of the left - lower - corner acoustic black hole structure is the vertical direction, then the well - placed acoustic black hole structure constitutes a right - handed eccentric acoustic black hole structure, as Figure 2 shown.

[0033] Due to the combined arrangement of the eccentricity of the chiral eccentric acoustic black hole structure of the present invention, it overcomes the incident - wave - direction dependence of the wave - aggregation characteristics of the traditional embedded acoustic black hole structure. Taking the chiral eccentric acoustic black hole structure composed of 4 eccentric acoustic black holes as a minimum unit, omnidirectional energy aggregation and wave rotation can be achieved.

[0034] In this specification, each embodiment is described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other. For the system disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple. For the relevant parts, refer to the description in the method part.

[0035] In this article, specific examples are used to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation on the present invention.

Claims

1. A chiral eccentric acoustic black hole structure, characterized in that, Comprising: Four acoustic black hole structures; The four acoustic black hole structures are placed in a well-like manner; a frustum-shaped cavity with an open top is wrapped inside each of the acoustic black hole structures; the circular area at the bottom of the cavity is an eccentric platform; the center of the eccentric platform is offset from the center of the acoustic black hole structure; A center-offset line segment is formed by connecting the center of the eccentric platform and the center of the acoustic black hole structure; The extension lines of the center-offset line segments of the four acoustic black hole structures are orthogonal to each other in pairs; Between the center of the eccentric platform and the center of the acoustic black hole structure, the center-offset direction is horizontal or vertical; In the well-like placed acoustic black hole structures, if the center-offset direction of the left-bottom acoustic black hole structure is horizontal, then the well-like placed acoustic black hole structures form a left-handed eccentric acoustic black hole structure; In the well-like placed acoustic black hole structures, if the center-offset direction of the left-bottom acoustic black hole structure is vertical, then the well-like placed acoustic black hole structures form a right-handed eccentric acoustic black hole structure; The thickness variation of a single acoustic black hole structure is shown in Equation (1): h(r, θ) = ε(r - r1) m + h1, (r1 ≤ r ≤ r2(θ))(1); Where h(r, θ) is the thickness of the acoustic black hole structure; r is the distance from any point inside the cavity to the center; θ is the polar angle; h1 is the minimum thickness of the acoustic black hole structure; r1 is the radius of the eccentric platform; r2(θ) is the radius of the top of the cavity; ε is the radius coefficient; m is the power exponent; And the radius r2(θ) of the top of the cavity is determined according to the following formula (2), and the radius coefficient ε is determined according to the following formula (3); Where h2 is the maximum thickness of the uniform plate; e is the offset distance between the center of the acoustic black hole structure and the center of the eccentric platform.

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