Experimental slamming and whipping investigation of ultralarge container ships in waves

To comprehensively investigate the slamming and whipping phenomena of an ultralarge container ship, a novel segmented model was designed and fabricated. On the basis of this segmented ship model, experimental investigations on slamming and whipping were conducted in the seakeeping basin of the CSSRC. This paper focuses on slamming and whipping when ships sail in severe waves. The test results revealed that the ship motion and vertical bending moment (VBM) per unit wave height exhibit great nonlinearity with increasing wave height; however, their nonlinear characteristics differ. Slamming and whipping increase the wave frequency components of sagging, hogging, and peak-to-peak VBM of midship SEC4 by 2.07, 1.34, and 1.75 times under a wave height corresponding to 14 m for a full-scale ship, respectively. When a ship sails in a severe oblique wave, it experiences not only vertical whipping but also horizontal and torsional whipping. The whipping characteristics in regular and irregular waves differ greatly. In addition, the reason why the maximum torsional moment is usually located at Stations 5 or 15 rather than at midship is revealed.