Surge effect during the water exit of an axisymmetric body traveling normal to a plane interface: experiments and BEM simulation

Abstract

 Experiments are presented on the surge effect induced by cylindrical bodies piercing a free surface at constant velocity. The study covers the following ranges: 0.1 < Froude² < 7.3, 0.7 < Weber < 89, 46 < Reynolds < 6000; with the Goucher number (Go) evolving between 1.8 and 4.5. Free-surface profiles are compared with those issued from a boundary element method (BEM) simulation based on potential theory and axisymmetric flow configuration. The free-surface deformation is accurately predicted by the BEM approach for Reynolds numbers (Re) higher than 500. However, for Re less than about 200, computed results underestimate the interface elevation, except on the axis of symmetry, where they remain accurate. Finally, the magnitudes of the interface deformation predicted by the numerical simulation are provided over a wide range of Goucher numbers (0.001 < Go < 50) both for hemispherical and conical tips. Implications of these results for phase detection probes are discussed.