Abstract
The wave-induced motions, and steady wave forces and moments for the oil tanker KVLCC2 in regular head and oblique waves are numerically predicted by using the expanded RANS solver based on OpenFOAM. New modules of wave boundary condition are programed into OpenFOAM for this purpose. In the present consideration, the steady wave forces and moments include not only the contribution of hydrodynamic effects but also the contribution of the inertial effects due to wave-induced ship motions. The computed results show that the contribution of the inertial effects due to heave and pitch in head waves is non-negligible when wave-induced motions are of large amplitude, for example, in long waves. The influence of wave amplitude on added resistance in head waves is also analyzed. The dimensionless added resistance becomes smaller with the increasing wave amplitude, indicating that added resistance is not proportional to the square of wave amplitude. However, wave amplitude seems not to affect the heave and pitch RAOs significantly. The steady wave surge force, sway force and yaw moment for the KVLCC2 with zero speed in oblique waves are computed as well. The present RANS results are compared with available experimental data, and very good agreements are found between them.
Highlights
Nowadays, environmental issues have become more and more prominent
Where X, Y and N are the mean force or moment, which are obtained by integrating pressure and viscous stress over hull surface; X0 is the clam-water resistance; X − X0 is added resistance due to the contribution of pure hydrodynamic effects; mwq and mwp are the mean inertia forces due to the coupled motions of heave, pitch and roll; mu is mean inertia force due to the surge acceleration; T is the transformation matrix, and T31 is the component at the third row of first column; mgT 31 and mgT 32 are the mean inertial forces due to gravity
New modules of wave boundary conditions are programed into OpenFOAM
Summary
Environmental issues have become more and more prominent. Green, efficient and sustainable development has become the main theme of human development. With the rapid development of computer performance, the numerical methods based on viscosity flow theory, especially the Reynolds-Average Navier–Stokes (RANS) method, are more and more widely used for the computation of ship hydrodynamic forces and moments in waves. Wu et al [22] calculated the added resistance for KVLCC2 in head short waves by RANS, and the numerical results are in good agreement with the experimental values They found that the increase of pressure near the ship’s bow contributed the most to the increase of resistance. Yao et al [31] computed the mean forces, moments and wave-induced six-DOF motions for KVLCC2 in the regular head wave and beam waves with the RANS method, and good agreement was shown by comparing the CFD results with the experimental data. The present works would supply a good reference for ship control [32]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
