Capillary phenomena occur in both natural and human-made systems, from equilibria in the presence of solids (grains, walls, metal wires) to multiphase flows in heterogeneous and fractured porous media. This book, composed of two volumes, develops fluid mechanics approaches for two immiscible fluids (water/air or water/oil) in the presence of solids (tubes, joints, grains, porous media). Their hydrodynamics are typically dominated by capillarity and viscous dissipation. This first volume presents...