Numerical Study on Propulsive Factors in Regular Head and Oblique Waves

Abstract

This paper applies Reynolds-averaged Navier-Stokes (RANS) method to study propulsion performance in head and oblique waves. Finite volume method (FVM) is employed to discretize the governing equations and SST k-ω model is used for modeling the turbulent flow. The free surface is solved by volume of fluid (VOF) method. Sliding mesh technique is used to enable rotation of propeller. Propeller open water curves are determined by propeller open water simulations. Calm water resistance and wave added resistances are obtained from towing computations without propeller. Self-propulsion simulations in calm water and waves with varying loads are performed to obtain self-propulsion point and thrust identify method is use to predict propulsive factors. Regular head waves with wavelengths varying from 0.6 to 1.4 times the length of ship and oblique waves with incident directions varying from 0° to 360° are considered. The influence of waves on propulsive factors, including thrust deduction and wake fraction, open water, relative rotative, hull and propulsive efficiencies are discussed.

Design of a new oscillating-buoy type wave energy converter and numerical study on its hydrodynamic performance

“…Fig 18. Turbofan dynamic pressure cloud at different periods By comparing the dynamic pressure cloud in Fig.18, it can be observed that the blade pressure distribution law is similar.…”

“…The computational domain is set based on the wave wavelength when wave period T = 1.5 s. The entrance boundary is located in the negative direction of the x-axis at a distance of 1λ from the origin, and the exit boundary is located in the positive direction of x-axis at a distance of 2λ from the origin, with a total length of 3λ. The computational domain is 2.56 m wide and 2.08 m high, with a water depth of 1 m and 1.08 m above the water surface, and it is encrypted near the water surface, in the background, and in the motion overlap area with a total of approximately 1 million computational grids [18][19]. The computational domain setup is illustrated in Fig.…”

Verification and Validation of CFD Simulations With Full-Scale Ship Speed/Power Trial Data

“…The Finite Volume Method (FVM), as described in [18], is used for spatial discretization of the governing equations. A first-order implicit Euler scheme is used for temporal discretization [21], and a second-order upwind scheme is used for the convection terms [22].…”

The effect of PID control scheme on the course-keeping of ship in oblique stern waves

“…Kim et al [27] simulated the course-keeping of the KCS container ship in waves and the turning motion in head waves using the CFD-based technique and investigated the effect of wavelength on ship manoeuvrability. Gong et al [28][29] applied the CFD method to simulate an autonomous trimaran in a stern wave and studied the effect of muzzle velocity on the sailing of a trimaran model in stern waves.…”