【作者】 杨磊； 徐恒； 王甫军；

【Author】 Yang Lei;Xu Heng;Wang Fujun;College of Civil and Transportation Engineering,Shenzhen University;Department of Mechanical and Aerospace Engineering, North Carolina State University;

【机构】 深圳大学土木与交通工程学院； 美国北卡罗来纳州立大学机械与航空航天系；

【摘要】 通过高速摄影技术获得了具有不同粘性的单个液滴撞击不同弹性模量的柔性材料表面铺展过程的时间序列,利用自行编写的Matlab程序对实验结果进行了图像识别,分析了最大铺展系数的变化规律,对液滴撞击柔性表面前的系统总能量与液滴铺展过程中移动接触线位置处"润湿脊"的运动导致的柔性材料粘弹性耗散进行了对比分析。研究结果表明,粘性系数的增大将明显降低最大铺展系数。对于具有较低弹性模量的柔性材料表面,"润湿脊"的粘弹性耗散在系统能量损耗中具有不可忽视的作用。高We数条件下,铺展过程中的液体粘性耗散能在系统能量耗散中占据主导地位,"润湿脊"的影响相对减弱。对于粘弹性耗散能的计算应考虑柔性材料剪切变形本构模型的应变率相关性。更多还原

【Abstract】 The spread procedure of a single droplet with different viscosity impacting on soft smooth surfaces with different modulus was captured by high-speed camera. The maximum spreading factor was achieved through image recognition technology by Matlab program. The total energy of the system and the viscoelastic dissipation caused by the "wetting ridge" around the moving contact line were analyzed. The results show that the increase of viscosity of liquid will significantly reduce the maximum spreading factor. The viscoelastic dissipation of "wetting ridge" plays an important role in the energy loss of the system for soft materials with low elastic modulus. Under the condition of high Weber number, the viscous dissipation energy of liquid plays a dominant role in the energy dissipation of the system, and the influence of "wetting ridge" is relatively weakened. For the calculation of viscoelastic dissipated, the strain-rate dependence of the constitutive model of shear deformation of soft materials should be considered.更多还原