In this paper, the results of plane turbulent wake given by Zhou Peiyuan are considered as the first order approximation and put, into the equations of turbulent fluctuation. The equations are solved numerically within the range of micro-scale by means of spectrum method. The double, triple and quadruple fluctuating velocity correlations are obtobred by computation. They are in a good agreement with experimental results.
The shock wave and turbulent boundary layer interaction induced by flat-faced blunt fin mounted on a flat plate is numerically studied. The calculation results display "A" shock wave structure generated by the impingement of separated shock with the bow shock. Some new phenomena are discovered in this flow through the simulation, such as the bifurcation and mergence of vortices in the separation region ahead of blunt fin, the existence of secondary separation and secondary vortex, multiple vortices structur...
MHD equations of the thermal convection flow in a conducting fluid is derived and a numerical simulation is presented for the thermal convection flow in the semiconductor crystal growth under a vertical magnetic field. Computational results show that oscillations and multiccll flow structure with separation at wall are effectively suppressed by the magnetic field with an appropriate strength, and that the stabilizing effects of magnetic field on the thermal convection flow increase with Hartmann number incr...
Using the concepts and method of finite-part integrals, the hypersingular integral equations of a plane crack loaded by arbitrary loads is proved exactly. The behaviour of the unknown solution are analysed theoretically and its indexes are then obtained. Based on these results, the singular stresses near the smooth point of the crack front are exactly derived by use of the dominant analyses. Then the stress intensity factors are expressed in terms of the displacement discontinuities of the crack surface. Fi...
The exact stationary solution for a general class of stochastically excited dissipative Hamiltonian systems is first obtained, based on which an equivalent nonlinear system method is then developed for similar but more general class of systems.
In this paper the equations of motion for the large deflection problem of a visco-elastic rectangular thin plate with initial curvature are expressed in terms of three displacements at the midplane. For a simply supported plate subjected to transverse load, the dynamic response of the plate under periodic load is studied, and the criterion of arising subharmonic bifurcation and the horseshoe (or chaotic) state is given by the bifurcation theory and the Melnikov's method.
The convective bifurcation of fluid through porous media in a square cavity heated from below is simulated numerically by the cubic spline method. This paper gives three critical points and presents the preliminary results for conditional stability.
This paper presents a simple analytical method solving the dynamic stress response in a solid sphere under thermal shock. From analytical expressions and calculating results we can observe that there is concentration of the dynamic stress at the center of a solid sphere and periodical oscillation due to the continual reflection of stress wave at the external boundary of the solid sphere.
Adopting an elastic-viscoplastic model, the asymptotic problem of mode Ⅲ moving crack-tip filld is investigated. This paper gives the forms of all asymptotic solutions through the analysis of the dynamic crack propagation and quasi-static crack growith problems, and proves that the quasi-statically growing crack solution is the special case of dynamic propagating solution.
An analytical technique on the Pfeiffer's method is suggested in the present paper to study the spinning liquid slosh problems. This technique extends the Pfeiffer's method to treat the spinning liquid slosh in various gravitational conditions.
In this paper, the theory proposed in two papers of Gao Ge's entitled "The universal physical equation of turbulence" and "The derivation of the universal physical equation of turbulence and relevant discussion" is analysed systematically, particular attention being paid to the part for incompressible turbulence, a representative of Gao Ge's theory. It is shown that the ensemble for the second average in those papers does not exist, both the turbulence-force hypothesis and effective-turbulence-force hypothe...