-The hydrodynamic coefficients C_d and C_m are not only dependent on the size of slender cylin-der,its location in water,KC number and Re number,but also vary with environmental conditions,i.e.,in regular waves or in ...-The hydrodynamic coefficients C_d and C_m are not only dependent on the size of slender cylin-der,its location in water,KC number and Re number,but also vary with environmental conditions,i.e.,in regular waves or in irregular waves,in pure waves or in wave-current coexisting field.In this paper,thenormalization of hydrodynamic coefficients for various environmental conditions is discussed.When aproper definition of KC number and proper characteristic values of irregular waves are used,a unified re-lationship between C_d,C_m and KC number for regular waves,irregular waves,pure waves and wave-cur-rent coexisting field can be obtained.展开更多
This study investigates the hydro-elastic behaviors of fully submerged horizontal cylinders in different regular waves.Two methods were proposed and compared in this study.The first method was based on potential theor...This study investigates the hydro-elastic behaviors of fully submerged horizontal cylinders in different regular waves.Two methods were proposed and compared in this study.The first method was based on potential theory in frequency domain and the discrete-module-beam(DMB)method,which discretizes a floating elastic structure into a sufficient number of rigid bodies while simultaneously representing the elastic behavior from beam elements with Euler-Bernoulli beam and Saint-Venant torsion.Moreover,the Morison method in time domain was employed;this method estimates wave forces from the semi-empirical Morison equation,and the elastic behavior is embodied by massless axial,bending,and torsional springs.Various parametric studies on cylinder diameter,submergence depth,and wave direction were conducted.Wave forces,dry/wet mode shapes/natural frequencies,and dynamic motions are presented and analyzed.展开更多
基金National Natural Science Foundation of China(No.59779005)
文摘-The hydrodynamic coefficients C_d and C_m are not only dependent on the size of slender cylin-der,its location in water,KC number and Re number,but also vary with environmental conditions,i.e.,in regular waves or in irregular waves,in pure waves or in wave-current coexisting field.In this paper,thenormalization of hydrodynamic coefficients for various environmental conditions is discussed.When aproper definition of KC number and proper characteristic values of irregular waves are used,a unified re-lationship between C_d,C_m and KC number for regular waves,irregular waves,pure waves and wave-cur-rent coexisting field can be obtained.
文摘This study investigates the hydro-elastic behaviors of fully submerged horizontal cylinders in different regular waves.Two methods were proposed and compared in this study.The first method was based on potential theory in frequency domain and the discrete-module-beam(DMB)method,which discretizes a floating elastic structure into a sufficient number of rigid bodies while simultaneously representing the elastic behavior from beam elements with Euler-Bernoulli beam and Saint-Venant torsion.Moreover,the Morison method in time domain was employed;this method estimates wave forces from the semi-empirical Morison equation,and the elastic behavior is embodied by massless axial,bending,and torsional springs.Various parametric studies on cylinder diameter,submergence depth,and wave direction were conducted.Wave forces,dry/wet mode shapes/natural frequencies,and dynamic motions are presented and analyzed.
