Honeycomb sandwich structure

Abstract

The invention provides a honeycomb sandwich structure. The honeycomb sandwich structure comprises an upper panel, a lower panel and a staggered honeycomb sandwich layer positioned between the upper panel and the lower panel, the staggered honeycomb sandwich layer comprises a plurality of honeycomb structure sub-layers, and the honeycomb structure sub-layers are coupled in a staggered manner through contact points; the upper panel is connected with the uppermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer, and the lower panel is connected with the lowermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of acoustics, in particular to a honeycomb sandwich structure. BACKGROUND

[0002] With the acceleration of industrialization, the expansion of transportation scale and the continuous improvement of urbanization level, noise pollution has become one of the global major environmental hazards, which poses a significant threat to public health and social well-being. In military and industrial application scenarios, high-intensity noise not only damages the physical and mental health and operation comfort of operating personnel, but also induces major technical risks such as measurement error of precision instruments and reliability degradation of electronic systems. Therefore, it is of urgent engineering significance to develop efficient noise control technology. The current main challenges and research hotspots focus on: under the strict constraints of quality, geometric size and material compatibility, efficient absorption or isolation of wide-band noise energy is realized.

[0003] In recent years, the equipment manufacturing industry such as aerospace vehicles, new energy vehicles and high-end ships has put forward higher requirements for structural function integration, and the demand for structural materials with lightweight, high reliability and excellent acoustic performance has increased rapidly. Especially in the field of aviation transportation, the improvement of structural weight reduction to fuel economy has become a key development goal. Under this background, the honeycomb sandwich structure is widely included in the lightweight acoustic design system due to its excellent specific stiffness, specific strength, high fatigue resistance and significant wide-band sound insulation efficiency, and has been more and more widely applied in many fields. The current honeycomb sandwich structure, due to its high specific stiffness characteristics, the matching effect appears in the medium and low frequency band, and compared with a single material plate, its influence frequency band is more extensive, which leads to the decline of the overall sound insulation performance.

[0004] Therefore, a new honeycomb sandwich structure is needed. SUMMARY

[0005] The purpose of the present application is to provide a honeycomb sandwich structure, which reduces the shear stiffness of the core layer by staggered honeycomb, maintains good mechanical properties of the honeycomb sandwich structure, eliminates the influence of the matching effect on the sound insulation of the structure, and realizes wide-band high sound insulation.

[0006] To achieve the above purpose, the present application provides a honeycomb sandwich structure, comprising: an upper panel, a lower panel and a staggered honeycomb core layer located between the upper panel and the lower panel.

[0007] The staggered honeycomb core layer comprises a plurality of honeycomb structure sub-layers, and the honeycomb structure sub-layers are coupled by staggered contact points; the upper panel is connected with the uppermost honeycomb structure sub-layer in the staggered honeycomb core layer, and the lower panel is connected with the lowermost honeycomb structure sub-layer in the staggered honeycomb core layer.

[0008] Preferably, the upper panel and the lower panel are metal plates, and the staggered honeycomb core layer is a resin material or a metal material.

[0009] Preferably, the staggered honeycomb sandwich layer is integrally formed by 3D printing technology.

[0010] Specifically, the thickness of the upper panel and the lower panel is 1mm, and the thickness of the staggered honeycomb sandwich layer is 20mm.

[0011] Specifically, the edge length of the honeycomb unit included in the staggered honeycomb sandwich layer is 20mm, and the wall thickness of the honeycomb unit is 2mm.

[0012] Specifically, the upper panel is connected with the uppermost honeycomb structure sublayer in the staggered honeycomb sandwich layer, and the lower panel is connected with the lowermost honeycomb structure sublayer in the staggered honeycomb sandwich layer, including: the upper panel is connected with the uppermost honeycomb structure sublayer in the staggered honeycomb sandwich layer by two-component adhesive, and the lower panel is connected with the lowermost honeycomb structure sublayer in the staggered honeycomb sandwich layer by two-component adhesive.

[0013] Specifically, the staggered honeycomb sandwich layer includes a plurality of honeycomb structure sublayers, including: the staggered honeycomb sandwich layer includes 2 honeycomb structure sublayers.

[0014] Preferably, the first space region and the second space region are separated by a honeycomb sandwich structure. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 An example diagram of a staggered honeycomb sandwich layer provided for an embodiment of the present application;

[0016] Figure 2 A schematic diagram of a 3D printed staggered honeycomb sandwich provided for an embodiment of the present application;

[0017] Figure 3 A schematic diagram of a honeycomb sandwich structure unit provided for an embodiment of the present application;

[0018] Figure 4 A top view of a honeycomb sandwich structure provided for an embodiment of the present application;

[0019] Figure 5 A sound insulation curve of a honeycomb sandwich structure and a single-layer honeycomb sandwich structure provided for an embodiment of the present application. DETAILED DESCRIPTION

[0020] The technical solutions of the present application will be further described in detail below with the help of the drawings and examples.

[0021] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below with reference to the drawings. It should be noted that similar reference numerals and letters in the following drawings represent similar items, and therefore, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings.

[0022] In the description of the embodiments of the present application, the words "exemplary", "for example", or "for instance" are used to mean serving as an example, instance, or illustration. Any embodiment or design described as "exemplary", "for example", or "for instance" in the embodiments of the present application should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of such terms is intended to present concepts in a particular manner. The term "exemplary" is used exclusively herein to refer to one example, instance, or implementation, and such term is not intended to convey preference or relation with respect to other examples, instances, or implementations.

[0023] At present, the honeycomb sandwich structure has realized large-scale application in the fields of high-speed train bodies, ship bulkheads, building interior and exterior decoration systems, high-performance sports equipment, racing car bodies and lightweight integrated houses, etc. due to its excellent specific stiffness, specific strength and lightweight characteristics. The structure is composed of a sandwich layer composed of two high-strength thin face panels (face layers) and a porous core material, and has excellent mechanical bearing performance. In terms of acoustic performance, the unique cell-enclosed cavity structure of the honeycomb core layer can effectively block heat flow transmission, and the multiple reflection and scattering of incident sound waves by the cavity wall can achieve sound energy attenuation, thereby giving the structure certain heat insulation and sound insulation functions. However, in some scenarios, it also has the following problems: its high specific stiffness characteristic can cause the bending wave speed of the structure to increase significantly, inducing a wide-band coincidence effect, especially forming a significant sound insulation trough in the medium-low frequency domain, and compared with a single material plate, its influence frequency band is more extensive, resulting in unstable sound insulation performance. That is, although the existing honeycomb sandwich structure has the advantages of heat insulation and medium-high frequency sound insulation, the high specific stiffness induces and aggravates the coincidence effect in the medium-low frequency domain, and the sound insulation curve has a deeper and wider trough in the medium-low frequency domain, resulting in an overall sound insulation performance that is not as stable as that of a homogeneous plate.

[0024] In order to overcome the deficiencies in the prior art and based on the above, a honeycomb sandwich structure containing a staggered honeycomb sandwich layer is proposed, which, without increasing the surface density and overall thickness of the structure, not only maintains the excellent bending resistance of the honeycomb sandwich structure, but also effectively eliminates the sound insulation trough caused by the coincidence effect, thereby achieving good sound insulation effect in a wider frequency band, and balancing the mechanical and acoustic performance.

[0025] Specifically, the honeycomb sandwich structure provided by the embodiments of the present application comprises: an upper panel, a lower panel and a staggered honeycomb sandwich layer located between the upper panel and the lower panel.

[0026] The staggered honeycomb sandwich layer comprises a plurality of honeycomb structure sub-layers, which are coupled by contact points; the upper panel is connected to the uppermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer, and the lower panel is connected to the lowermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer.

[0027] For example, the staggered honeycomb sandwich layer comprises two honeycomb structure sub-layers, which are coupled by contact points; the upper panel is connected to the uppermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer by a two-component adhesive, and the lower panel is connected to the lowermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer by a two-component adhesive.

[0028] Figure 1 A schematic diagram of a staggered honeycomb sandwich layer provided by an embodiment of the present application is shown in the figure, in which the upper and lower honeycomb structures are staggered and connected only by contact points.

[0029] In one embodiment, the upper and lower panels are metal plates, and the staggered honeycomb sandwich layer is made of resin or metal material. The staggered honeycomb sandwich layer is integrally formed by 3D printing technology.

[0030] Figure 2 A schematic diagram of a 3D-printed staggered honeycomb sandwich layer provided by an embodiment of the present application is shown in the figure, in which the staggered honeycomb sandwich layer with only point contact between the upper and lower layers is prepared by 3D printing. In addition to the staggered honeycomb sandwich layer made of resin, the staggered honeycomb sandwich layer made of aluminum also has the effect of reducing the shear stiffness of the sandwich layer and eliminating the influence of the anastomosis effect on the structure sound insulation. The upper and lower panels are aluminum plates. A uniform thin layer of AB glue is applied to the glue pool, and the prepared staggered honeycomb sandwich layer is placed in the glue pool for light pressing to ensure that the glue is evenly applied to the wall surface of the honeycomb core. Then, the honeycomb core is taken out and adhered to the aluminum plate to ensure that the honeycomb core is in full contact with the aluminum plate and is firmly bonded.

[0031] In different embodiments, the thickness of the upper and lower panels and the staggered honeycomb sandwich layer can be different. In a specific embodiment, the thickness of the upper and lower panels is 1 mm, and the thickness of the staggered honeycomb sandwich layer is 20 mm.

[0032] Figure 3 A schematic diagram of a honeycomb sandwich structure unit provided by an embodiment of the present application is shown in the figure, in which h f is the thickness of the upper panel, the thickness of the lower panel is the same as that of the upper panel, which is 1 mm, and h f is the thickness of the lower panel. C is the thickness of the lower panel. C is the thickness of the staggered honeycomb sandwich layer.

[0033] In different embodiments, the edge length of the honeycomb unit included in the honeycomb structure sublayer and the wall thickness of the honeycomb unit can be different. In one specific embodiment, the edge length of the honeycomb unit included in the honeycomb structure sublayer is 20 mm, and the wall thickness of the honeycomb unit is 2 mm.

[0034] Figure 4 A top view of a honeycomb sandwich structure provided in an embodiment of the present application is shown in the figure. l = 20 mm, l is the edge length of the honeycomb unit included in the honeycomb structure sublayer, and t = 2 mm, t is the wall thickness of the honeycomb unit.

[0035] In one embodiment, the sound insulation between the first space region and the second space region separated by a honeycomb sandwich structure.

[0036] Figure 5 A sound insulation curve of a honeycomb sandwich structure and a single-layer honeycomb sandwich structure provided in an embodiment of the present application is shown in the figure. STL represents sound transmission loss. The average sound insulation amount of the honeycomb sandwich structure in the range of 100 Hz-3000 Hz is increased by 2.4 dB compared with that of the single-layer honeycomb sandwich structure with the same thickness.

[0037] The above detailed description further describes the purpose, technical solutions and beneficial effects of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A honeycomb sandwich structure comprising: The upper panel, the lower panel and the staggered honeycomb sandwich layer between the upper panel and the lower panel; The staggered honeycomb sandwich layer comprises a plurality of honeycomb structure sub-layers, and the honeycomb structure sub-layers are coupled by contact points. The upper panel is connected with the uppermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer, and the lower panel is connected with the lowermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer.

2. The honeycomb sandwich structure of claim 1, wherein, The upper panel and the lower panel are metal plates, and the staggered honeycomb sandwich layer is a resin material or a metal material.

3. The honeycomb sandwich structure of claim 1, wherein, The staggered honeycomb sandwich layer is integrally formed by a 3D printing technology.

4. The honeycomb sandwich structure of claim 2, wherein, The thickness of the upper panel and the lower panel is 1 mm, and the thickness of the staggered honeycomb sandwich layer is 20 mm.

5. The honeycomb sandwich structure of claim 2, wherein, The side length of the honeycomb unit included in the staggered honeycomb sandwich layer is 20 mm, and the wall thickness of the honeycomb unit is 2 mm.

6. The honeycomb sandwich structure of claim 1, wherein, The upper panel is connected with the uppermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer, and the lower panel is connected with the lowermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer, comprising: the upper panel is connected with the uppermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer by a two-component adhesive, and the lower panel is connected with the lowermost honeycomb structure sub-layer in the staggered honeycomb sandwich layer by a two-component adhesive.

7. The honeycomb sandwich structure of claim 1, wherein, The staggered honeycomb sandwich layer comprises a plurality of honeycomb structure sub-layers, comprising: the staggered honeycomb sandwich layer comprises 2 honeycomb structure sub-layers.

8. The honeycomb sandwich structure of claim 1, wherein, The honeycomb sandwich structure is used for sound insulation between the first space region and the second space region separated by the honeycomb sandwich structure.

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