Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering Conference
Shanghai, China, June 5–10, 2022
Copyright © 2022 by the International Society of Offshore and Polar Engineers (ISOPE)
ISBN 978-1-880653-81-4; ISSN 1098-6189

www.isope.org

Numerical analysis on ship-to-ship Hydrodynamic interaction in waves by using Taylor Expansion
Boundary Element Method
Bo Yang, Kai-bo Yu, Yuan-bo Gao
Department of Navigation, Dalian Naval Academy
Dalian, Liaoning, China

elimination of the scale effect is also a problem. With the continuous
improvement of computer performance, the development of numericalcalculation based on experimental results is developing rapidly.

ABSTRACTA numerical model of ship-to-ship hydrodynamic interactions wasestablished based on the Taylor Expansion Boundary Element Method(TEBEM), and the validity and accuracy of the proposed method wereverified based on the published ship model test data. And the model
was used to calculate the hydrodynamic interactions of two ships under
different conditions such as speed, transverse distance, longitudinaldistance, wave height and frequency, and the effects of the above
factors on the hydrodynamic interactions of two ships were analyzed.

Korsmeyer et al. (1993) studied the interaction force of two ships inrestricted waters, which considered the influences of bank wall andbottom. Sutulo et al. (2012) developed a potential flow code to
calculate the ship-to-ship interaction force, obtained suitable
recommended values for grid convergence and computational
efficiency trade-offs. Xu et al. (2014) considered the influence of freesurface and calculated the interaction force between two barges,
especially made a detailed study on the wave surface between the twoships. Yuan et al. (2015) considered the free surface effect anddeveloped the MHydro program, which used the Rankine source
method to limit the motion in the directions except heave and pitch, andstudied the overtaking problem of two ships.

KEY WORDS: ship-to-ship interaction; TEBEM; transverse force;yaw moment.
With the rapid development of the shipping industry and the continuous
increase of the tonnage of ships, some ship maneuvering problems,such as ship encounters, underway replenishment work, and multi-ship
obstacle avoidance strategies, have attracted great attention ofresearchers. If two ships are close to each other, the transverse force
and yaw moment generated by the interaction between the ships have agreat influence on the maneuverability of the ship, and even lead to aship collision accident. Therefore, the hydrodynamic interaction lawsof ships advancing parallel in close proximity (especially in waves)need further study.

In addition to potential flow methods, CFD methods have also been
increasingly used in recent years to predict ship-to-ship interaction
forces. Sadat-Hosseini et al. (2011) used the URANS method to solve
the interaction force when different types of ships remained relatively
stationary at the same speed. Zhang et al. (2012) adopted the dynamic
mesh technique without considering the free surface, solved theunsteady RANS equation, and simulated the encounter of two ships inshallow water. Based on the RANS equation, Zou and Larsson (2013)used KVLCC2 and Aframax ships to study this problem, consideringfactors such as ship speed, water depth, and transverse distance,respectively. Mousaviraad et al. (2016) analyzed ship-ship interaction
tests under still water and waves respectively, and focused on using
CFD method to simulate ship-to-ship interaction based on URANS.

Researches on the hydrodynamic interaction of two floating bodies aremainly dominated by the model test and numerical calculation. In theaspect of model test, Newton (1960) explored the overtaking problemof two ships in deep water; Remery (1974) discussed the interaction
effect of the advancing ship to a mooring ship in Netherlands Ship
Model Basin. Vantorre (2002) conducted a relatively comprehensive
captive model tests, and obtained the hydrodynamic interaction force
through the cross test of four ship models, and analyzed the influenceof ship speed, transverse distance, water depth and other conditions indetail, and based on this, obtained an empirical formula. Comparedwith numerical calculation, the ship model test is expensive, and theFrom the above research status, it can be seen that there are still many
problems to be solved in ship-to-ship hydrodynamic interaction. TheCFD method is limited to the problem of computational efficiency andcannot be widely used in engineering calculations. The potential flow
theory method has made great progress, but the calculation accuracy of3568