A NUMERICAL STUDY ON THE EFFECT OF WATER DEPTH ON SHIP HYDRODYNAMIC DERIVATIVES

Ships behave differently in shallow water when compared to deep water. Added resistance & sluggishness to manoeuvre are the common effects of shallow water conditions. This highlights the necessity of studying ship manoeuvring characteristics in shallow water. In the present study, variation of hydrodynamic derivativeswith respect to water depth is studied. Horizontal planar motion mechanism (HPMM) under different shallow water conditions are numerically simulated using anUnsteady-Reynolds Averaged Navier-Stokes (URANS) based commercial solver.Several empirical formulas are available for predicting the shallow water derivatives, but most of them are for conventional ships. A new regression expression is proposed for estimating the hydrodynamic derivatives based on the simulated results.