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1.
This work is the continuation of the discussion of ref.[1].In ref.[1] we applied thetheory of functions of a complex variable under Dirac-Pauli representation,introduced theKaluza“Ghost”coordinate, and turned Navier-Stokes equations of viscofluid dynamics ofhomogeneous and incompressible fluid into nonlinear equation with only a pair of complexunknown functions.In this paper we again combine the complex independent variableexcept time,and cause it to decrease in a pair to the number of complex independentvariables.Lastly,we turn Navier-Stokes equations into classical Burgers equation.TheCole-Hopf transformation join up with Burgers equation and the diffusion equation isB(?)cklund transformation in fact,and the diffusion equation has the general solution aseveryone knows.Thus,we obtain the exact solution of Navier-Stokes equations byB(?)cklund transformation.  相似文献   

2.
This work is the continuation of the discussion of Ref.[1].In this Paper we resoive theequations of isentropic gas dynamics into two problems:the three-dimensional non-constant irrotational flow (thus the isentropic flow,too),and the three-dimensional non-constant indivergent flow (i.e.the in compressible isentropic flow).We apply the theory offunctions of a complex variable under Dirac-Pauli representation and the Legendretransformation,transform these equations of two problems from physical space intovelocity space,and obtain two general Chaplygin equations in this paper.The generalChaplygin equation is a linear difference equation,and its general solution can be expressedat most by the hypergeometric functions.Thus we can obtain the general solution of generalproblems for the three-dimensional non-constant isentropic flow of gas dynamics.  相似文献   

3.
This work is the continuation of the discussion of refs.[1-2].We discuss thedynamics problems of ideal rigid—plastic material in the flow theory of plasticity in thispaper.From introduction of the theory of functions of complex variable under Dirac-Paulirepresentation we can obtain a group of the so-called“general equations”(i.e.have twoscalar equations)expressed by the stream function and the theoretical ratio.In this paperwe also testify that the equation of evolution for time in plastodynamics problema is neitherdissipative nor disperive,and the eigen-equation in plastodynamics problems is a stationarySchr(?)dinger equation,in which we take partial tensor of stress-increment as eigenfunctionsand take theoretical ratio as eigenvalues.Thus,we turn nonlinear plastodynamics problemsinto the solution of linear stationary Schr(?)dinger equation,and from this we can obtain thegeneral solution of plastodynamics problems with rigid-plastic material.  相似文献   

4.
This work is the continuation and improvement of the discussion of Ref.[1]. We alsoimprove the discussion of Refs.[2-3] on the elastic large deflection problem by results ofthis paper.We again simplify the von Kármán equation for elastic large deflection problem,and finally turn it into the nonlinear Schr(?)dinger equation in this paper.Secondly,weexpand the AKNS equation to still more symmetrical degree under many dimensionalconditions in this paper.Owing to connection between the nonlinear Schr(?)dinger equationand the integrability condition for the AKNS equation or the Dirac equation,we can obtainthe exact solution for elastic large deflection problem by inverse scattering method.In otherwords,the elastic large deflection problem wholly becomes a quantum eigenvalues problem.The large deflection problem with orthorhombic anisotropy is also deduced in thispaper.  相似文献   

5.
This work is the continuation of the discussion of Refs.[1-5].In this paper:[A] The Love-Kirchhoff equations of vibration problem with small deflection fororthorhombic anisotropic thin shells or orthorhombic anisotropic thin plates on Winkler’sbase are classified as several of the same solutions of Schr?dinger equation.and we canobtain the general solutions for the two above-mentioned problems by the method in Refs.[1]and[3-5].[B]The von Kármán-Vlasov equations of large deflection problem for shallow shellswith orthorhombic anisotropy(their special cases are the von Kármán equations of largedeflection problem for thin plates with orthorhombic anisotropy)are classified as thesolutions of AKNS equation or Dirac equation,and we can obtain the exact solutions forthe two abovementioned problems by the inverse scattering method in Refs.[4-5].The general solution of small deflection problem or the exact solution of largedeflection problem for the corrugated or rib-reinforced plates and shells as special c  相似文献   

6.
This work is the continuation and the distillation of the discussion of Refs. [1-4].(A)From complementarity principle we build up dissipation mechanics in this paper.It is a dissipative theory of correspondence with the quantum mechanics.From this theorywe can unitedly handle problems of macroscopic non-equilibrium thermodynamics andviscous hydrodynamics. and handle each dissipative and irreversible problems in quantummechanics.We prove the basic equations of dissipation mechanics to eigenvalues equationsof correspondence with the Schr(?)dinger equation or Dirac equation in this paper.(B)We unitedly merge the basic nonlinear equations of dissipative type, especially theNavier-Stokes equation as a basic equation for macroscopic non-equilibrium ther-modynamics and viscous hydrodynamics into integrability condition of basic equation ofdissipation mechanics. And we can obtain their exact solutions by the inverse scatteringmethod in this paper.  相似文献   

7.
The general bending problem of conical shells on the elastic foundation (Winkler Medium) is not solved. In this paper, the displacement solution method for this problem is presented. From the governing differential equations in displacement form of conical shell and by introducing a displacement function U(s,θ), the differential equations are changed into an eight-order soluble partial differential equation about the displacement function U(s,θ) in which the coefficients are variable. At the same time, the expressions of the displacement and internal force components of the shell are also given by the displacement function U(s θ). As special cases of this paper, the displacement function introduced by V.S. Vlasov in circular cylindrical shell, the basic equation of the cylindrical shell on the elastic foundation and that of the circular plates on the elastic foundation are directly derived. Under the arbitrary load, and boundary conditions, the general bending problem of the conical shell on the elas  相似文献   

8.
In this paper.variable operator and its product with shifting operator are studied.The product of power series of shifting operator with variable coefficient is defined andits convergence is proved under Mikusinski’s sequence convergence.After turning ageneral variable coefficient linear difference equation of order n into a set of operatorequations.we can obtain the solutions of the general n-th order variable coefficientlinear difference equation.  相似文献   

9.
This paper derives the cubic spline beam function from the generalized beam differential equation and obtains the solution of the discontinuous polynomial under concentrated loads, concentrated moment and uniform distributed by using delta function. By means of Kantorovich method of the partial differential equation of elastic plates which is transformed by the generalized function (δ function and σ function), whether concentrated load, concentrated moment, uniform distributed load or small-square load can be shown as the discontinuous polynomial deformed curve in the x-direction and the y-direction. We change the partial differential equation into the ordinary equation by using Kantorovich method and then obtain a good approximate solution by using Glerkin’s method. In this paper there ’are more calculation examples involving elastic plates with various boundary-conditions, various loads and various section plates, and the classical differential problems such as cantilever plates are shown.  相似文献   

10.
The random response of a piezoelectric thick shell in plane strain state under boundary random excitations is studied and illustrated with a piezoelectric cylindrical shell. The differential equation for electric potential is integrated radially to obtain the electric potential as a function of displacement. The random stress boundary conditions are converted into homogeneous ones by transformation,which yields the electrical and mechanical coupling differential equation for displacement under random excitations. Then this partial differential equation is converted into ordinary differential equations using the Galerkin method and the Legendre polynomials,which represent a random multi-degree-of-freedom system with asymmetric stiffness matrix due to the electrical and mechanical coupling and the transformed boundary conditions. The frequency-response function matrix and response power spectral density matrix of the system are derived based on the theory of random vibration. The mean-square displacement and electric potential of the piezoelectric shell are finally obtained,and the frequency-response characteristics and the electrical and mechanical coupling properties are explored.  相似文献   

11.
In this paper the outcome of axisymmetric problems of ideal plasticity in paper[39],[19]and[37]is directly extended to the three-dimensional problems of ideal plasticity,andget at the general equation in it.The problem of plane strain for material of ideal rigid-plasticity can be solved by putting into double hormonic equation by famous Pauli matricesof quantum electrodynamics different from the method in paper[7].We lead to the eigenequation in the problems of ideal plasticity,taking partial tenson of stress-increment aseigenfunctions,and we are to transform from nonlinear equations into linear equation inthis paper.  相似文献   

12.
According to the differential equation for transverse displacement function of anisotropic rectangular thin plates in free vibration, a general analytical solution is established. This general solution, composed of the composite solutions of trigonometric function and hyperbolic function, can satisfy the problem of arbitrary boundary conditions along four edges. The algebraic polynomial with double sine series solutions can also satisfy the problem of boundary conditions at four corners. Consequently, this general solution can be used to solve the vibration problem of anisotropic rectangular plates with arbitrary boundaries accurately. The integral constants can be determined by boundary conditions of four edges and four corners. Each natural frequency and vibration mode can be solved by the determinate of coefficient matrix from the homogeneous linear algebraic equations equal to zero. For example, a composite symmetric angle ply laminated plate with four edges clamped has been calculated and discussed.  相似文献   

13.
This work is the continuation of the discussions of[50]and[51].In this paper:(A)The Love-Kirchhoff equation of small deflection problem for elastic thin shellwith constant curvature are classified as the same several solutions of Schr(?)dingerequation,and we show clearly that its form in axisymmetric problem;(B)For example for the small deflection problem,we extract the general solution ofthe vibration problem of thin spherical shell with equal thickness by the force in centralsurface and axisymmetric external field,that this is distinct from ref.[50]in variable.Today the variable is a space-place,and is not time;(C)The von Kármán-Vlasov equation of large deflection problem for shallow shellare classified as the solutions of AKNS equations and in it the one-dimensional problem isclassified as the solution of simple Schr(?)dinger equation for eigenvalues problem,and wetransform the large deflection of shallow shell from nonlinear problem into soluble linearproblem.  相似文献   

14.
The first-passage statistics of Duffing-Rayleigh- Mathieu system under wide-band colored noise excitations is studied by using stochastic averaging method. The motion equation of the original system is transformed into two time homogeneous diffusion Markovian processes of amplitude and phase after stochastic averaging. The diffusion process method for first-passage problem is used and the corresponding backward Kolmogorov equation and Pontryagin equation are constructed and solved to yield the conditional reliability function and mean first-passage time with suitable initial and boundary conditions. The analytical results are confirmed by Monte Carlo simulation.  相似文献   

15.
A Donnell type theory is developed for finite deflection of closely stiffened truncatedlaminated composite conical shells under arbitrary loads by using the variational calculusand smeared-stiffener theory.The most general bending-stretching coupling and the effectof eccentricity of stiffeners are considered.The equilibrium equations,boundary conditionsand the equation of compatibility are derived.The new equations.of the mixed-type ofstiffened laminated composite conical shells are obtained in terms of the transversedeflection and stress function.The simplified equations are also given for some commonlyencountered cases.  相似文献   

16.
This work is the continuation of the discussion of Refs. [1-5]. In this paper:[A] The Love-Kirchhoff equations of vibration problem with small deflection for orthorhombic misotropic thin shells or orthorhombic anisotropic thin plates on Winkler’s base are classified as several of the same solutions of Schrodmger equation, and we can obtain the general solutions for the two above-mentioned problems by the method in Refs. [1] and [3-5].[B] The. von Karman-Vlasov equations of large deflection problem for shallow shells with orthorhombic anisotropy (their special cases are the von Harmon equations of large deflection problem for thin plates with orthorhombic anisotropy) are classified as the solutions of AKNS equation or Dirac equation, and we can obtain the exact solutions for the two abovementioned problems by the inverse scattering method in Refs. [4-5].The general solution of small deflection problem or the exact solution of large deflection problem for the corrugated or rib-reinforced plates and shells as special cases is included in this paper.  相似文献   

17.
An optimal time-delay feedback control method is provided to mitigate the primary resonance of a single-walled carbon nanotube (SWCNT) subjected to a Lorentz force excited by a longitudinal magnetic field. The nonlinear governing equations of motion for the SWCNT under longitudinal magnetic field are derived and the modulation equations are obtained by using the method of multiple scales. The regions of the stable feedback gain are worked out by using the stability conditions of eigenvalue equation. Taking the attenuation ratio as the objective function and the stable vibration regions as constrained conditions, the optimal control parameters are worked out by using minimum optimal method. The optimal controllers are designed to control the dynamic behaviors of tile nonlinear vibration systems. It is found that the optimal feedback gain obtained by the optimal method can enhance the control performance of the primary resonance of SWCNT devices.  相似文献   

18.
In this paper an equation of motion is presented for a general thick viscoelastic plate, including the effects of shear deformation, extrusion deformation and rotatory inertia. This equation is the generalization of equations of motion for the corresponding thick elastic plate, and it can be degenerated into several types of equations for various special cases.  相似文献   

19.
Stability related to theoretical model for catastrophic weather prediction, which includes non-hydrostatic perfect elastic model and anelastic model, is discussed and analyzed in detail. It is proved that non-hydrostatic perfect elastic equations set is stable in the class of infinitely differentiable function. However, for the anelastic equations set, its continuity equation is changed in form because of the particular hypothesis for fluid, so "the matching consisting of both viscosity coefficient and incompressible assumption" appears, thereby the most important equations set of this class in practical prediction shows the same instability in topological property as Navier-Stokes equation, which should be avoided first in practical numerical prediction. In light of this, the referenced suggestions to amend the applied model are finally presented.  相似文献   

20.
This paper derives the cubic spline beam function from the generalized beamdifferential equation and obtains the solution of the discontinuous polynomial underconcentrated loads,concentrated moment and uniform distributed by using delta function.By means of Kantorovich method of the partial differential equation of elastic plates whichis transformed by the generalized function(δ function and σ function),whetherconcentrated load,concentratedmoment,uniform distributed load or small-square load canbe shown as the discontinuous polynomial deformed curve in the x-direction and the y-direction.We change the partial diffkerential equation into the ordinary equation by usingKantorovich method and then obtain a good approximate solution by using Glerkin’smethod.In this paper there are more calculation examples involving elastic plates withvarious bounndary-conditions,various loads and various section plates,and the classicaldifferential problems such as cantilever plates are shown.  相似文献   

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