A numerical model based upon both the characteristic method and the equations of continuity and momentum is presented for simulating the movement of hydraulic jumps in circular cross-sectional conduits under the unste...A numerical model based upon both the characteristic method and the equations of continuity and momentum is presented for simulating the movement of hydraulic jumps in circular cross-sectional conduits under the unsteady flow conditions. The hydraulic jump, in the numerical simulation of unsteady flow with a moving discontinuity,was treated as a moving boundary within the computational domain defined by the spacetime grid. The laboratory tests under the unsteady flow conditions were carried out to examine the applicability of the presented numerical model of the hydraulic jump movement. Complete test results for a range of Froude numbers are presented that may be used by other researchers for the verification of mathematical model. The inclusion of initial and boundary condition is investigated. A comparison of the computed and measured results shows that the agreement between them is satisfactory.展开更多
Vibrational power flow on combined plates with a change in mass and stiffness or with viscoelastic damping layer used widely in engineering is studied. The expressions of flexural displacement and other physical quan...Vibrational power flow on combined plates with a change in mass and stiffness or with viscoelastic damping layer used widely in engineering is studied. The expressions of flexural displacement and other physical quantities are obtained using Laplace transformation and transfer matrix approach, then influences of changes in mass and stiffness of discontinuous material and the free damping layer on the input power flow and the transmitted power flow are discussed. The conclusions provide theory basis for structural optimization design and reducing noise and vibration展开更多
文摘A numerical model based upon both the characteristic method and the equations of continuity and momentum is presented for simulating the movement of hydraulic jumps in circular cross-sectional conduits under the unsteady flow conditions. The hydraulic jump, in the numerical simulation of unsteady flow with a moving discontinuity,was treated as a moving boundary within the computational domain defined by the spacetime grid. The laboratory tests under the unsteady flow conditions were carried out to examine the applicability of the presented numerical model of the hydraulic jump movement. Complete test results for a range of Froude numbers are presented that may be used by other researchers for the verification of mathematical model. The inclusion of initial and boundary condition is investigated. A comparison of the computed and measured results shows that the agreement between them is satisfactory.
文摘Vibrational power flow on combined plates with a change in mass and stiffness or with viscoelastic damping layer used widely in engineering is studied. The expressions of flexural displacement and other physical quantities are obtained using Laplace transformation and transfer matrix approach, then influences of changes in mass and stiffness of discontinuous material and the free damping layer on the input power flow and the transmitted power flow are discussed. The conclusions provide theory basis for structural optimization design and reducing noise and vibration
