Steady two-dimensional fluid flow over an obstacle is solved using complex variable methods. We consider the cases of rectangular obstacles, such as large boulders, submerged in a potential flow. These may arise in geophysics, marine and civil engineering. Our models are applicable to initiation of motion that may result in subsequent transport. The local flow depends on the obstacle shape, slowing down in confining corners and speeding up in expanding corners. The flow generates hydrodynamic forces, drag and lift, and their associated moments, which differ around each face. Our model replaces the need for ill-defined drag and lift coefficients with geometry-dependent functions. We predict smaller flow velocities to initiate motion. We show how a joint-bound boulder can be transported against gravity, and analyse the influence of a wake region behind an isolated boulder.

中文翻译：

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淹没矩形障碍物上的势流：引发巨石运动的后果

使用复杂变量方法求解障碍物上的稳定二维流体流动。我们考虑淹没在潜在流中的矩形障碍物的情况，例如大石块。这些可能出现在地球物理学、海洋和土木工程中。我们的模型适用于可能导致后续运输的运动的启动。局部流动取决于障碍物的形状，在限制角落时减速，在扩大角落时加速。流动产生流体动力、阻力和升力，以及它们相关的力矩，这些力矩在每个面周围都不同。我们的模型用几何相关函数取代了对不明确的阻力和升力系数的需求。我们预测较小的流速来启动运动。我们展示了如何克服重力运输联合绑定的巨石，