CN-122020755-A - Body-centered cubic sandwich super structure with low-frequency broadband characteristic and working method thereof

Abstract

The invention relates to a body-centered cubic sandwich super structure with low-frequency broadband characteristics and a working method thereof, wherein the super structure comprises a plurality of unit cell structures which are periodically arranged along an X direction and a Y direction, the unit cell structures comprise an upper panel, an inner truss structure and a lower panel which are sequentially arranged from top to bottom, a body center position of the inner truss structure is provided with a spiral beam-mass block local resonance unit, the spiral beam-mass block local resonance unit comprises at least one Archimedean spiral beam and a mass block, one end of the Archimedean spiral beam is fixed with the mass block, and the other end of the Archimedean spiral beam is fixed with a body center node of the inner truss structure. The invention has simple structure and high structural integration level, and the body-centered cubic sandwich frame embedded by the Archimedes spiral beam vibrator unit can utilize a multi-mode local resonance mechanism without damaging the surface of a panel to generate obvious bending wave band gap in a low frequency band through ingenious built-in design.

Inventors

• CHEN XIAOCHAO
• CHENG LIN

Assignees

• 福州大学

Dates

Publication Date

20260512

Application Date

20260128

Claims (10)

1. 1. The body-centered cubic sandwich super structure with the low-frequency broadband characteristic is characterized by comprising a plurality of unit cell structures which are periodically arranged along the X direction and the Y direction, wherein each unit cell structure comprises an upper panel, an inner truss structure and a lower panel which are sequentially arranged from top to bottom, a body center position of the inner truss structure is provided with a spiral beam-mass block local resonance unit, the spiral beam-mass block local resonance unit comprises at least one Archimedean spiral beam and a mass block, one end of each Archimedean spiral beam is fixed with the mass block, and the other end of each Archimedean spiral beam is fixed with a body center node of the inner truss structure.
2. 2. The body centered cubic sandwich super structure with low frequency broadband characteristics according to claim 1, wherein the internal truss structure comprises an upper truss and a lower truss, the upper truss and the lower truss are each formed by a plurality of columns, one ends of the columns are respectively fixed with the upper panel or the lower panel, and the other ends of the columns are connected into a whole.
3. 3. A body centered cubic sandwich super structure having low frequency broadband characteristics as recited in claim 1, wherein said mass is cylindrical.
4. 4. A body centered cubic sandwich super structure with low frequency broadband characteristics as claimed in claim 1, wherein a plurality of archimedes screw beams within said unit cell structure are provided to form a multi-vibrator synergistic effect.
5. 5. A body centered cubic sandwich super structure with low frequency broadband characteristics as claimed in claim 1, wherein two rows of unit cell structures are arranged along the Y direction, each row of unit cell structures being arranged with twenty eight along the X direction.
6. 6. The body centered cubic sandwich super structure with the low frequency broadband characteristic according to claim 1, wherein the side length of the upper panel and the lower panel is 46mm, the thickness is 0.5mm, the height of the internal truss structure is 19mm, the initial radius of the Archimedean spiral beam is 2mm, the end radius is 16mm, the thickness and the width are 2mm and 1mm respectively, the diameter of the mass block is 12mm, and the height is 10mm.
7. 7. The body-centered cubic sandwich super structure with the low-frequency broadband characteristic according to claim 1, wherein the upper panel, the lower panel and the inner truss structure are made of aluminum alloy, young modulus is 69 GPa, density is 2713kg/m3, poisson ratio is 0.3, archimedes spiral beam is made of stainless steel, young modulus is 193GPa, density is 8027kg/m3, poisson ratio is 0.3, mass block is made of lead, young modulus is17 GPa, density is 11340kg/m3, and poisson ratio is 0.42. The overall density of the structure is 573.512 kg/m3.
8. 8. A body centered cubic sandwich super structure with low frequency broadband characteristics according to claim 1, wherein the upper and inner truss structures, the inner truss structure and lower panel, the inner truss structure and the local resonance unit of the spiral beam-mass block, the archimedes spiral beam and the mass block are all welded or bonded.
9. 9. A method of operating a body centered cubic sandwich super structure with low frequency broadband characteristics according to claim 1 wherein when the low frequency bending wave propagates through the upper or lower panel of the unit cell structure, the internal truss structure transmits excitation to the archimedes' spiral beams and cylindrical vibrators of the spiral beam-mass local resonance unit, exciting their multi-modal vibrations, which modes couple with the elastic wave, forming a band gap that inhibits wave propagation.
10. 10. The method of claim 1, wherein the multi-modal vibrations of the helical beam-mass localized resonating unit include in-plane swing, torsion and out-of-plane vibrations to facilitate coupling with bending waves propagating through the upper and lower panels, and wherein bending wave band gaps are created in the low frequency band based on localized resonating mechanisms.

Description

Body-centered cubic sandwich super structure with low-frequency broadband characteristic and working method thereof Technical Field The invention relates to a body-centered cubic sandwich super structure with low-frequency broadband characteristics and a working method thereof. Background With the continuous pursuit of light weight and high performance in the fields of aerospace, high-speed vehicles, precision instruments and the like, a lattice sandwich structure is favored because of its excellent high specific strength and high specific rigidity. However, this structure generally has problems of significant low-frequency vibration transmission and slow energy attenuation, which affect the stability and reliability of the equipment. The existing vibration damping method is divided into active control and passive control, wherein the active control depends on external energy and a complex system, but the system is complex and has poor environmental adaptability although the vibration of a specific frequency band can be accurately restrained, and the passive control has a simple and reliable structure and limited low-frequency vibration damping effect and often reduces bearing capacity. In recent years, the metamaterial brings new opportunities for vibration control, and a band gap for inhibiting elastic wave propagation can be generated through periodical microstructure design, wherein the local resonance metamaterial can realize low-frequency control in a sub-wavelength scale. However, existing solutions for combining localized resonating units with sandwich structures have limitations in that surface attachment destroys structural integrity and functionality, and in that the panel type weakens load bearing properties and it is difficult to meet both low frequency and broadband vibration damping requirements. Disclosure of Invention The invention improves the problems, namely the invention provides a body-centered cubic sandwich super structure with low-frequency broadband characteristics and a working method thereof, and the body-centered cubic sandwich frame embedded with Archimedes spiral beam vibrator units can generate remarkable bending wave band gap in a low frequency band by ingenious built-in design without damaging the surface of a panel by utilizing a multi-mode local resonance mechanism. The invention is composed by that it includes a plurality of unit cell structures which are arranged periodically along X direction and Y direction, the unit cell structure includes upper panel, inner truss structure and lower panel which are set up from top to bottom, the body center of the inner truss structure is equipped with a spiral beam-mass block local resonance unit, the spiral beam-mass block local resonance unit includes at least one Archimedes spiral beam and mass block, one end of the Archimedes spiral beam is fixed with the mass block, the other end is fixed with the body center node of the inner truss structure. Further, the internal truss structure comprises an upper truss and a lower truss, the upper truss and the lower truss are formed by a plurality of columns, one ends of the columns are respectively fixed with the upper panel or the lower panel, and the other ends of the columns are connected into a whole. Further, the mass block is cylindrical. Furthermore, a plurality of Archimedes spiral beams in the unit cell structure are arranged to form a multi-vibrator synergistic effect. Further, two rows of unit cell structures are arranged along the Y direction, and twenty-eight unit cell structures are arranged along the X direction. Further, the side lengths of the upper panel and the lower panel are 46mm, the thickness is 0.5mm, the height of the internal truss structure is 19mm, the initial radius of the Archimedes spiral beam is 2mm, the end radius is 16mm, the thickness and the width are 2mm and 1mm respectively, the diameter of the mass block is 12mm, and the height is 10mm. Further, the upper panel, the lower panel and the inner truss structure are made of aluminum alloy, young modulus is 69 GPa, density is 2713kg/m3, poisson's ratio is 0.3, archimedes spiral beams are made of stainless steel, young modulus is 193GPa, density is 8027kg/m3, poisson's ratio is 0.3, mass blocks are made of lead, young modulus is 17GPa, density is 11340kg/m3, and Poisson's ratio is 0.42. The overall density of the structure is 573.512 kg/m3. Further, welding or bonding is adopted between the upper panel and the inner truss structure, between the inner truss structure and the lower panel, between the inner truss structure and the local resonance unit of the spiral beam-mass block, and between the Archimedes spiral beam and the mass block. Further, in the working method of the body-centered cubic sandwich super structure with the low-frequency broadband characteristic, when the low-frequency bending wave propagates through the upper panel or the lower panel of the unit cell structure, the internal truss struct