CFD Analysis of Unsteady Yaw Motion of A Towed Ship

Abstract

Instability of  a towed ship presented in the form of her unstable yaw  motion  may  lead  to  serious  accident  especially  at  the restricted waterways such as colliding with other ships or onshore structures.  To  stabilize  this  unsteady  yaw  motion,  a comprehensive investigation is then required to ensure a safety of ship's  towing  navigation.  This  paper  presents  a  computational fluid  dynamic  (CFD)  approach  to  analyse  yaw  motion characteristics of a towed ship incorporated with an asymmetrical bridle towline model. Several towing parameters such as towing’s angles and speeds have taken into account. Here, a towed ship or barge  in  then  called  as  1B  is  employed  in  this  simulation.  The results  revealed  that  the  subsequent  increase  of  towing's  angle dealt  with  a  better  yaw  motion  of  1B  indicated  by  sufficient reduction  of  her  sway  motion  associated  with  more  steady  yaw motion of a towed ship.