Calculation of Horizontal Sectional Loads and Torsional Moment

Abstract

Horizontal sectional loads (horizontal shear force and horizontal bending moment) and torsional moment are more difficult to predict with potential flow methods than vertical loads, especially in sternquartering waves. Accurate computation of torsional moment is especially important for large modern container ships. The threedimensional (3D) seakeeping code GL Rankine has been applied previously to the computation of vertical loads in head, following and oblique waves; this paper addresses horizontal loads and torsional moment in oblique waves at various forward speeds for a modern container ship. The results obtained with the Rankine sourcepatch method are compared with the computations using zerospeed freesurface Green functions and with model experiments.