This paper presents the experimental results of impulsive waves caused by subaerial landslides. A wide range of effective parameters are considered and studied by performing 120 laboratory tests. Considered slide masses are both rigid and deformable. The effects of bed slope angle, water depth, slide impact velocity, geometry, shape and deformation on impulse wave characteristics have been inspected. The impulse wave features such as amplitude, period and also energy conversation are studied. The effects of slide Froude number and deformation on energy conversation from slide into wave are also investigated. Based on laboratory measured data an empirical equation for impulse wave amplitude and period have been presented and successfully verified using available data of previous laboratory works.

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Meniscus motion in a capillary tube is a very common type of flow in thermal management devices such oscillating and pulsating heat pipes. It is well known, that the thin film deposited on the wall, which is due to liquid shear force, plays a major role in heat and mass transfer of those devices. This study focuses on the hydrodynamics of this flow using a CFD axisymmetric model of a 1mm diameter capillary, with the approach of volume of fluid (VoF). The CFD-VOF approach is tuned to capture the liquid film deposition from a receding meniscus at different constant velocities. Due to high required grid resolution, the moving overset mesh technique is used. In doing so, a fine meshed domain consists of meniscus slides over the background domain with a coarse mesh. By using this technique, the number of cells and computational time reduced considerably in comparison with regular meshing approach. With water as a working fluid, the numerical results for the liquid film thickness, at different velocities, compare well with experimental data from the literature. The simulations also show that at higher capillary number, the axial location where the film thickness becomes constant moves away from the meniscus nose. The shear stress distribution indicates higher values near the meniscus compared to uniform film and liquid plug zones which is due to the interface curvature in this zone. Also, a recirculating flow was observed within the liquid film left behind the receding meniscus which could have favourable effects in terms of heat and mass transfer. The present work on hydrodynamics is the first step toward complete modelling of an oscillating meniscus with mass and heat transfer inside the capillaries.

Meniscus motion in a capillary tube is a very common type of flow in thermal management devices such as oscillating and pulsating heat pipes. It is well known, that the thin film deposited on the wall, which is due to liquid shear force, plays a major role in the heat and mass transfer of those devices. This study focuses on the hydrodynamics of this flow using a CFD axisymmetric model of a 1mm diameter capillary, with the approach of the volume of fluid (VoF). The CFD-VOF approach is tuned to capture the liquid film deposition from a receding meniscus at different constant velocities. Due to the high required grid resolution, the moving overset mesh technique is used. In doing so, a fine-meshed domain consists of meniscus slides over the background domain with a coarse mesh. By using this technique, the number of cells and computational time are reduced considerably in comparison with the regular meshing approach. With water as a working fluid, the numerical results for the liquid film thickness, at different velocities, compare well with experimental data from the literature. The simulations also show that at a higher capillary number, the axial location where the film thickness becomes constant moves away from the meniscus nose. The shear stress distribution indicates higher values near the meniscus compared to uniform film and liquid plug zones which is due to the interface curvature in this zone. Also, a recirculating flow was observed within the liquid film left behind the receding meniscus which could have favorable effects in terms of heat and mass transfer. The present work on hydrodynamics is the first step toward complete modeling of an oscillating meniscus with mass and heat transfer inside the capillaries.

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