This paper presents a numerical investigation of ship manoeuvring under the combined effect of bank and propeller. The incompressible turbulent flow with free surface around the self-propelled hull form is simulated u...This paper presents a numerical investigation of ship manoeuvring under the combined effect of bank and propeller. The incompressible turbulent flow with free surface around the self-propelled hull form is simulated using a commercial CFD software (ANSYS-FLUENT). In order to estimate the influence of the bank-propeller effect on the hydrodynamic forces acting on the ship, volume forces representing the propeller are added to Navier-Stokes equations. The numerical simulations are carried out using the equivalent of experiment conditions. The validation of the CFD model is performed by comparing the numerical results to the availa- ble experimental data. For this investigation, the impact of Ship-Bank distance and ship speed on the bank effect are tested with and without propeller. An additional parameter concerning the advance ratio of the propeller is also tested.展开更多
In this study,the dynamic behavior of a developed bypass viscous damper is evaluated.Bypass viscous damper has a flexible hose as an external orifice through which the inside fluid transfer from one side to the other ...In this study,the dynamic behavior of a developed bypass viscous damper is evaluated.Bypass viscous damper has a flexible hose as an external orifice through which the inside fluid transfer from one side to the other side of the inner piston.Accordingly,the viscosity coficient of the damper can be adjusted using geometrical dimensions of the hose.Moreover,the external orifice acts as a thermal compensator and alleviates viscous heating of the damper.According to experimental results,Computational Fluid Dynamic(CFD)model,a numerical formula and the simplified.Maxwell model are found and assessed;therefore,the verification of numerical and computational models are evaluated for simulating.Also,a simplifed procedure is proposed to design structures with bypass viscous dampers.The design procedure is applied to design an 8-story hospital structure with bypass viscous dampers,and it is compared with the same structure,which is designed with concentric braces and without dampers.Nonlinear time history analyses revealed that the hospital with viscous damper experiences less structural inelastic demands and fewer story accelerations which mean fewer demands on nonstructural elements.Moreover,seismic behaviors of nonstructural masonry claddings are also compared in the cases of hospital structure with and without dampers.展开更多
文摘This paper presents a numerical investigation of ship manoeuvring under the combined effect of bank and propeller. The incompressible turbulent flow with free surface around the self-propelled hull form is simulated using a commercial CFD software (ANSYS-FLUENT). In order to estimate the influence of the bank-propeller effect on the hydrodynamic forces acting on the ship, volume forces representing the propeller are added to Navier-Stokes equations. The numerical simulations are carried out using the equivalent of experiment conditions. The validation of the CFD model is performed by comparing the numerical results to the availa- ble experimental data. For this investigation, the impact of Ship-Bank distance and ship speed on the bank effect are tested with and without propeller. An additional parameter concerning the advance ratio of the propeller is also tested.
文摘In this study,the dynamic behavior of a developed bypass viscous damper is evaluated.Bypass viscous damper has a flexible hose as an external orifice through which the inside fluid transfer from one side to the other side of the inner piston.Accordingly,the viscosity coficient of the damper can be adjusted using geometrical dimensions of the hose.Moreover,the external orifice acts as a thermal compensator and alleviates viscous heating of the damper.According to experimental results,Computational Fluid Dynamic(CFD)model,a numerical formula and the simplified.Maxwell model are found and assessed;therefore,the verification of numerical and computational models are evaluated for simulating.Also,a simplifed procedure is proposed to design structures with bypass viscous dampers.The design procedure is applied to design an 8-story hospital structure with bypass viscous dampers,and it is compared with the same structure,which is designed with concentric braces and without dampers.Nonlinear time history analyses revealed that the hospital with viscous damper experiences less structural inelastic demands and fewer story accelerations which mean fewer demands on nonstructural elements.Moreover,seismic behaviors of nonstructural masonry claddings are also compared in the cases of hospital structure with and without dampers.