金字塔点阵圆筒结构轴向弹性波传递特性研究

AXIAL ELASTIC WAVE PROPAGATION CHARACTERISTICS OF PYRAMID LATTICE CYLINDRICAL STRUCTURE

点阵结构的周期和多孔特征使其相较于普通的实体结构具有轻质、耐冲击、减振降噪和高比强度等优势,在航空航天和船舰等领域具有十分广泛的应用前景.本文以金字塔点阵圆筒结构为对象,根据单胞的宽、高和阵列的个数等独立的结构参数进行参数化建模,并利用商用有限元软件计算了点阵圆筒结构轴向振动特性.通过无量纲手段针对归一化频率和相对带宽,系统研究了单胞的宽、高以及杆件直径等关键参数对减振效果的影响.根据参数分析的结果,设计了一种具有低频宽带减振性能的金字塔点阵圆筒结构.使用增材制造技术制作了样件,并进行了振动测试实验,结果表明,实验和有限元模拟的结果基本一致,在500~1500 Hz范围内,结构表现出明显的减振效果,平均的衰减强度达到了50 d B左右.

The lattice structure is a porous periodic structure which has the advantages of light weight, high specific strength, high impact resistance, vibration reduction, noise reduction. Meanwhile, the lattice structure has broad application prospects in aerospace, transportation, and other fields. This paper takes the pyramid lattice cylinder structure as the object, The parametric model is determined by independent structural parameters such as width, height and number of arrays, etc. and commercial finite element software was used to calculate the axial vibration characteristics of lattice structure. The influence of key parameters such as cell width, cell height and rod diameter on the damping effect was studied by the dimensionless parameters of normalized frequency and relative bandwidth. Through parameter analysis, a pyramid lattice cylinder structure with low frequency and broadband vibration damping performance has been designed.Then a sample is made by additive manufacturing. The vibration test results show that the experimental results are consistent with the finite element simulation. In the range of 500 Hz to 1500 Hz, the structure shows obvious vibration reduction effect, and the average attenuation strength reaches about 50 dB.