Vector Analysis Of Morison's Equation

Abstract

For the evaluation of drag force due to wave or wave-current action, the Morison equation is commonly used in conjunction with only the horizontal component of the water particle velocity. However, for a horizontal cylinder in waves, or in waves and current, the vertical component of the water particle velocity is significant For such a case, Morison's equation should be modified to the vector form. Therefore, the analysis of horizontal cylinder hydrodynamic load due to wave or simultaneous wave-current action, taking into account the vertical component of the water particle velocity as well, has been carried out in the paper. It has been clearly shown that the vertical component of the water particle velocity needs to be considered too, because of the considerable differences in the drag force values in relation to the model that do not take into account the velocity vertical component.