The paper deals with the mathematical modelling of a gas slug rising in a cylindrical duct filled with an incompressible liquid. This research is motivated by a phenomenon commonly observed during Strombolian eruptions at basaltic volcanoes, that is, mildly explosive events driven by a large bubble of magmatic gas (a slug) rising up the conduit and bursting at the surface. The model is compared with the laboratory experiments described in [15] and we prove that the constancy of the slug ascent velocity observed in these experiments is fully justifiable. The model is developed both in the case of a Newtonian fluid and in the case of a non-Newtonian power law fluid, more suitable for magmas, and applied to a volcanic scenario.

中文翻译：

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圆柱管中上升的气团的建模及其在火山岩中的应用

本文研究了气体塞在充满不可压缩液体的圆柱形管道中上升的数学模型。这项研究的动机是在玄武岩火山在Strombolian喷发期间通常观察到的一种现象，即由岩浆气体大气泡（弹头）上升到管道并在地表破裂而引起的轻度爆炸事件。该模型与[15]中描述的实验室实验进行了比较，我们证明了在这些实验中观察到的弹头上升速度的恒定性是完全合理的。该模型是在牛顿流体和非牛顿幂律流体的情况下开发的，更适合于岩浆，并适用于火山岩情况。