ABSTRACT The hydrodynamic impact contributes to the initiation of subaerial boulder transport by tsunamis and tsunami-like flows. Here, we consider two approaches to modelling this impact force—hydrostatic and hydrodynamic—and assess the suitability of each in boulder transport models. The model proposed, solved as an ordinary differential equation, eliminates the need to assume a conservative value of flow acceleration. Introducing the hydrodynamic impact force reduces, by almost 45%, the recognised overestimation of threshold flow velocity in simple hydrodynamic models for boulder transport. By contrast, including the hydrostatic impact force reduces the overestimation by less than 10%. We found the new model consistent with the results of simple flume experiments. In these experiments, three rectangular limestone blocks of 27-70 cm3 in subaerial pre-transport setting condition were subjected to tsunami-like flow by sudden opening of a sluice gate.

中文翻译：

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水动力冲击力在海啸空中输运巨石中的作用——实验证据及巨石输运方程修正

摘要 水动力冲击有助于海啸和类似海啸的流动引发地下巨石运输。在这里，我们考虑两种方法来模拟这种冲击力——静水力和流体动力——并评估每种方法在巨石运输模型中的适用性。提出的模型作为常微分方程求解，无需假设流动加速度的保守值。引入流体动力冲击力将在简单流体动力学模型中用于巨石运输的阈值流速的公认高估降低了近 45%。相比之下，包括静水冲击力可以将高估减少不到 10%。我们发现新模型与简单水槽实验的结果一致。在这些实验中，