In this paper, the influence of temperature on longitudinal expansion of high-altitude bridge is discussed through conducting force analysis to the separated body of railway construction plaza project high-altitude br...In this paper, the influence of temperature on longitudinal expansion of high-altitude bridge is discussed through conducting force analysis to the separated body of railway construction plaza project high-altitude bridge. The specific implementation method includes: firstly, establishing a second-order linear homogeneous differential equation, combining with the initial conditions of longitudinal expansion of bridge, then obtaining the analytical solution of structural motion equation. In the end, the influence of the simplification of damping index on the structural motion equation is discussed.展开更多
In this paper, the theory of constructing optimal dynamical systems based on weighted residual presented by Wu & Sha is applied to three-dimensional Navier-Stokes equations, and the optimal dynamical system modeli...In this paper, the theory of constructing optimal dynamical systems based on weighted residual presented by Wu & Sha is applied to three-dimensional Navier-Stokes equations, and the optimal dynamical system modeling equations are derived. Then the multiscale global optimization method based on coarse graining analysis is presented, by which a set of approximate global optimal bases is directly obtained from Navier-Stokes equations and the construction of optimal dynamical systems is realized. The optimal bases show good properties, such as showing the physical properties of complex flows and the turbulent vortex structures, being intrinsic to real physical problem and dynamical systems, and having scaling symmetry in mathematics, etc.. In conclusion, using fewer terms of optimal bases will approach the exact solutions of Navier-Stokes equations, and the dynamical systems based on them show the most optimal behavior.展开更多
文摘In this paper, the influence of temperature on longitudinal expansion of high-altitude bridge is discussed through conducting force analysis to the separated body of railway construction plaza project high-altitude bridge. The specific implementation method includes: firstly, establishing a second-order linear homogeneous differential equation, combining with the initial conditions of longitudinal expansion of bridge, then obtaining the analytical solution of structural motion equation. In the end, the influence of the simplification of damping index on the structural motion equation is discussed.
基金supported by the National Natural Science Foundation of China(Grant Nos.11372068 and 11572350)the National Basic Research Program of China(Grant No.2014CB744104)
文摘In this paper, the theory of constructing optimal dynamical systems based on weighted residual presented by Wu & Sha is applied to three-dimensional Navier-Stokes equations, and the optimal dynamical system modeling equations are derived. Then the multiscale global optimization method based on coarse graining analysis is presented, by which a set of approximate global optimal bases is directly obtained from Navier-Stokes equations and the construction of optimal dynamical systems is realized. The optimal bases show good properties, such as showing the physical properties of complex flows and the turbulent vortex structures, being intrinsic to real physical problem and dynamical systems, and having scaling symmetry in mathematics, etc.. In conclusion, using fewer terms of optimal bases will approach the exact solutions of Navier-Stokes equations, and the dynamical systems based on them show the most optimal behavior.
