Approximate models of interacting surfaces competed against a supercomputer solution Describing the way two surfaces touch and make contact may seem simple, but it is not. Fully describing the elastic deformation of ideally smooth contacting bodies, under even low applied pressure, involves second-order partial differential equations and fourth-rank elastic constant tensors. For more realistic rough surfaces, the problem becomes a multiscale exercise in surface-height statistics, even before including complex phenomena such as adhesion, plasticity, and fracture. A recent research competition, the “Contact Mechanics Challenge” (1), was designed to test various approximate methods for solving this problem. A hypothetical rough surface was generated, and the community was invited to model contact with this surface with competing theories for the calculation of properties, including contact area and pressure. A supercomputer-generated numerical solution was kept secret until competition entries were received. The comparison of results (2) provides insights into the relative merits of competing models and even experimental approaches to the problem.

中文翻译：

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粗糙表面的接触运动

与超级计算机解决方案竞争的交互表面的近似模型 描述两个表面接触和接触的方式可能看起来很简单，但事实并非如此。完全描述理想光滑接触体的弹性变形，即使在施加很小的压力下，也涉及二阶偏微分方程和四阶弹性常数张量。对于更逼真的粗糙表面，该问题成为表面高度统计中的多尺度练习，甚至在包括粘附、塑性和断裂等复杂现象之前也是如此。最近的一项研究竞赛“接触力学挑战赛”(1) 旨在测试解决此问题的各种近似方法。生成了一个假设的粗糙表面，并邀请社区使用竞争理论对与该表面的接触进行建模，以计算属性，包括接触面积和压力。在收到参赛作品之前，超级计算机生成的数值解决方案一直保密。结果 (2) 的比较提供了对竞争模型的相对优点的见解，甚至是解决问题的实验方法。