Date: 02/13/09

Speaker: H. Yan

Title: Water Impact of Axisymmetric Bodies

Abstract:
The problem of water surface impact by an axisymmetric object vertically dropping toward
the calm water surface is considered. Fully nonlinear simulations are employed to
investigate this nonlinear fluid-object interaction problem. The focus is on the
understanding of the impact phenomenon at relatively low Froude number (with Fr=V/(gL)1/2
= O(1), where V is the entry velocity of the body, g the gravitational acceleration, and
L the characteristic length of the body). In particular, our objectives are to quantify
the range of validity of existing asymptotic theories and to understand the gravity
effect upon the impact process. This study is of direct relevance to reliable and
accurate prediction of hydrodynamic loads associated with ship slamming and extreme
surface wave impact on marine structures.