分子弹簧的隔振机理与力学性能研究

INVESTIGATION OF MOLECULAR SPRING ON VIBRATION ISOLATION MECHANISM AND MECHANICAL PROPERTIES

分子弹簧是一种由水和布满微孔的疏水沸石颗粒组成的隔振缓冲介质.当振动、冲击发生时,随着外力对分子弹簧加载卸载,水分子进出沸石颗粒的疏水微孔,实现能量的存储、释放和消耗.通过疏水微孔内液柱受力平衡和界面层热力学平衡分别建立了水侵入单条疏水微孔的模型,分段模拟了水分子侵入大量疏水微孔的过程,推导了分子弹簧受压过程中力--变形的关系,采用准静态试验对理论分析结果进行了验证,并计算了分子弹簧的隔振性能,结果表明:理论与试验结果具较好的一致性,分子弹簧在加载与卸载过程中呈现高--低--高的三段分段刚度,使得分子弹簧隔振系统在工作段具有极低固有频率,特别适合于低频重载情况下的隔振缓冲应用.

Molecular spring is a kind of vibration isolation and shock absorption medium which consists of water and hydrophobic zeolites. In the case of vibration and impact, loading and unloading take turns. Water intrudes into and extrudes from hydrophobic pores of zeolites and at the same time stores, releases and dissipates energy. Force equilibrium of water column in pore and interfacial layer thermodynamic equilibrium are used separately to establish the mechanics model of water intruding into a single hydrophobic pore. Then water flowing into large numbers of hydrophobic pores is calculated considering that contact angle distribution is Gaussian and aperture is uniform. And force-displacement curve of molecular spring is derived. The theoretical result shows good agreement with quasi-static experimental data. Finally,the vibration isolation property is assessed by energy transmissibility. The result shows that the stiffness of molecular spring mixture is piecewise nonlinear with high-low-high three parts and the system with molecular spring isolator has low nature frequency during working. Therefore, molecular spring is suitable for heavy equipment with low frequencies.