According to the requirement of high-performance development modern ships, it is necessary quickly and accurately predict maneuverability ships under wave conditions. In this paper, based on CFD (Computational Fluid Dynamics) method in commercial software STAR-CCM+, numerical simulation roll decay motion, pure heel heave pitch motion ship model 5415 carried out. The relevant hydrodynamic deriva...

An approach combining frequency and time domain analysis is introduced in this study for ship motions assessment. The open-source NEMOH code utilized to compute the excitation forces hydrodynamic coefficients, while heave pitch histories are determined by solving Cummins equations domain. compares numerical outcomes heave, pitch, vertical acceleration at center of gravity with data obtained fro...

Ship motion problem is approached exploiting the assumption of linearity and subdividing forces acting on the hull in different components; in this paper the focus is on the radiation problem. A fully viscous solver, based on the numerical solution of the Navier-Stokes equation through the finite volume technique, is used to calculate radiation forces on hull surface, with non linear free surfa...

This paper presents a practical scheme to control heave motion for hover and automatic landing of a Rotary-wing Unmanned Aerial Vehicle (RUAV) in the presence of strong horizontal gusts. A heave motion model is constructed for the purpose of capturing dynamic variations of thrust due to horizontal gusts. Through construction of an effective gust estimator, a feedback-feedforward controller is d...

In this study, the authors proposed explicit formulae of surge, heave, and pitch motion ship in regular waves expressed as function principal hull-form parameters extracted dominant those for simple estimation wave loads structural design. order to develop which have enough accuracy wide range applicability, theoretical approach was adopted based on linear seakeeping theory. process deriving fo...

This paper presents a constrained finite horizon model predictive control (MPC) scheme for regulation of the annular pressure in a well during managed pressure drilling from a floating vessel subject to heave motion. In addition the robustness of a controller to deal with heave disturbances despite uncertainties in the friction factor and bulk modulus is investigated. The stochastic model descr...

Abstract With the continuous development of dredging business to overseas markets, ships are faced with a more and complex hydrodynamic environment. Swell long wave periods has great impact on adaptability ship operations. Focused Trailing Suction Hopper Dredger (TSHD), this paper studied motion response characteristics TSHD under influence swell. The result shows that is severely affected by a...

The rescue of ships in distress at sea relies mainly on vessels, which includes the approaching process and towing motion two ships. Ship can be reduced to a two-ship problem, primarily involving relative between during rescue. We established mathematical model ship based viscous fluid N-S equation, Wigley under waves was simulated two-dimensional plane. Then, according three-dimensional potent...