标题： 表面张力梯度在确定微观动态接触角中的作用 显示英文标题

标题： The role of surface tension gradient in determining microscopic dynamic contact angle

摘要： 根据吉布斯对界面作为分割面的解释，我们通过为包含界面和接触线的控制体积写出力平衡来推导微观动态接触角的模型。在这样做时，我们发现除了各自界面的表面张力外，表面张力的梯度在确定动态接触角中起着重要作用。这是因为它不仅有助于产生额外的力，还解释了局部表面张力偏离其静态平衡值的情况。结果显示，这种表面张力的梯度可以归因于接触线附近对流加速度，而这种对流加速度是该区域滑移程度不同的直接结果。此外，我们提供了证据表明，这种表面张力的梯度是导致稳定移动接触线的前缘和后缘接触角差异的关键因素之一。这些发现通过分子动力学模拟得到了验证。 显示英文摘要

摘要： Following Gibb's interpretation of an interface as a dividing surface, we derive a model for the microscopic dynamic contact angle by writing a force balance for a control volume encompassing the interfaces and the contact line. In doing so we identify that, in addition to the surface tension of respective interfaces, the gradient of surface tension plays an important role in determining the dynamic contact angle. This is because not only does it contribute towards an additional force, but it also accounts for the deviation of local surface tension from its static equilibrium value. It is shown that this gradient in surface tension can be attributed to the convective acceleration in the vicinity of the contact line, which in turn is a direct result of varying degree of slip in that region. In addition, we provide evidence that this gradient in surface tension is one of the key factors responsible for the difference in contact angle at the leading and trailing edge, of a steadily moving contact line. These findings are validated using molecular dynamics simulations.