Mathermatical modelling of gravity-driven flows in environmental settings

已经观察到，在一定条件下，在开放的倾斜通道中稳定地排放流体并不会导致均匀的流体层的流动。取而代之的是，水流沿其表面呈现出一系列间歇性的孔，这种模式被称为“滚波”。这种现象的发生在人工管道中产生了重要的后果，如明渠、径流渠道和大坝溢洪道。相关的钻孔可能会损坏流量控制和流量测量设备，并且可能高到足以将液位提升到超出通道的限制。沿倾斜表面自然产生的流动也可能涉及滚波。例如，在暴雨期间后在山区产生的泥石流或由火山喷发引发的泥石流可以形成大的间歇性钻孔，以足够的力量冲下山坡，造成广泛的财产损失，甚至造成生命损失。此外，随着横波的出现，流体层底部的剪应力显著增加，加剧了土壤侵蚀。

It has been observed that, under certain conditions, the steady discharge of fluid in an open inclined channel does not result in the flow of a uniform fluid layer. Instead, the flow exhibits a series of intermittent bores along its surface, a pattern referred to as "roll waves". The occurrence of this phenomenon has important consequences in artificial conduits such as open aqueducts, run-off channels, and spillways from dams. The associated bores can damage flow control and flow measuring devices, and may be sufficiently high to raise the fluid level beyond the constraints of the channel. Naturally occurring flows along inclined surfaces can also involve roll waves. Mudflows, for example, generated in mountainous regions after intense rainy periods or initiated by volcanic eruptions can develop large intermittent bores that surge downhill with enough force to inflict extensive property damage and even loss of life. Furthermore, soil erosion is exacerbated by the significant increase in shear stress at the bottom of the fluid layer associated with the appearance of roll waves.