The demand for high-speed boats that operating near to shoreline is increasing nowadays.Understanding the behavior and attitude of high-speed boats when moving in different waterways is very important for boat designe...The demand for high-speed boats that operating near to shoreline is increasing nowadays.Understanding the behavior and attitude of high-speed boats when moving in different waterways is very important for boat designer.This research uses a CFD(Computational Fluid Dynamics)analysis to investigate the shallow water effects on prismatic planing hull.The turbulence fl ow around the hull was described by Reynolds Navier Stokes equations RANSE using the k-ɛturbulence model.The free surface was modelled by the volume of fl uid(VOF)method.The analysis is steady for all the ranges of speeds except those close to the critical speed range Fh=0.84 to 1.27 due to the propagation of the planing hull solitary waves at this range.In this study,the planing hull lift force,total resistance,and wave pattern for the range of subcritical speeds,critical speeds,and supercritical speeds have been calculated using CFD.The numerical results have been compared with experimental results.The dynamic pressure distribution on the planing hull and its wave pattern at critical speed in shallow water were compared with those in deep water.The numerical results give a good agreement with the experimental results whereas total average error equals 7%for numerical lift force,and 8%for numerical total resistance.The worst effect on the planing hull in shallow channels occurs at the critical speed range,where solitary wave formulates.展开更多
Hydrodynamics of planing hulls is affected by proximity to the seabed floor in shallow waters.In this study,a three-dimensional steady linearized model based on the potential theory is applied to model flat planing su...Hydrodynamics of planing hulls is affected by proximity to the seabed floor in shallow waters.In this study,a three-dimensional steady linearized model based on the potential theory is applied to model flat planing surfaces at finite water depth and finite Froude numbers.Modeling results for shallow waters agree with experimental data in the subcritical and supercritical regimes sufficiently far from the critical speed that corresponds to the depth Froude number of unity.At the critical speed,nonlinear and unsteady effects become important,and a different modeling approach is required.展开更多
文摘The demand for high-speed boats that operating near to shoreline is increasing nowadays.Understanding the behavior and attitude of high-speed boats when moving in different waterways is very important for boat designer.This research uses a CFD(Computational Fluid Dynamics)analysis to investigate the shallow water effects on prismatic planing hull.The turbulence fl ow around the hull was described by Reynolds Navier Stokes equations RANSE using the k-ɛturbulence model.The free surface was modelled by the volume of fl uid(VOF)method.The analysis is steady for all the ranges of speeds except those close to the critical speed range Fh=0.84 to 1.27 due to the propagation of the planing hull solitary waves at this range.In this study,the planing hull lift force,total resistance,and wave pattern for the range of subcritical speeds,critical speeds,and supercritical speeds have been calculated using CFD.The numerical results have been compared with experimental results.The dynamic pressure distribution on the planing hull and its wave pattern at critical speed in shallow water were compared with those in deep water.The numerical results give a good agreement with the experimental results whereas total average error equals 7%for numerical lift force,and 8%for numerical total resistance.The worst effect on the planing hull in shallow channels occurs at the critical speed range,where solitary wave formulates.
文摘Hydrodynamics of planing hulls is affected by proximity to the seabed floor in shallow waters.In this study,a three-dimensional steady linearized model based on the potential theory is applied to model flat planing surfaces at finite water depth and finite Froude numbers.Modeling results for shallow waters agree with experimental data in the subcritical and supercritical regimes sufficiently far from the critical speed that corresponds to the depth Froude number of unity.At the critical speed,nonlinear and unsteady effects become important,and a different modeling approach is required.
