无限元剖析过程(国外英文资料).doc

有限元分析过程(国外英文资料) The basic variables in elastic mechanics include the boundary conditions of displacement, stress and strain: displacement boundary conditions and stress boundary conditions Plane stress problem: thin sheet only on the edge of the plate is parallel to the board face and does not force along the thickness change of surface, including zero stress components have zero stress component () the () of (8) independent of the unknown variables (). Plane strain problem: infinite long column form, on the cross section is parallel to the cross section and do not force along the thickness change of surface, including zero strain component has a nonzero strain component is () () a total of eight independent unknown quantity (). The difference: the plane stress is the true two-dimensional distribution state, and the plane strain is the three-dimensional stress state. The plane strain (sigma z is not the size of sigma x, sigma y) The function of the virtual work equation: the process of the analytical solution of elastic mechanics is too complicated, so the analysis is greatly simplified from the Angle of energy. Virtual work principle: assume that load in elastomer, a possible displacement, arbitrary, smile, under the condition of equilibrium, the elastic strain energy in the body should be equal to the external force by virtual work. Each column in the first matrix K elements of physical meaning is: to force of the structure of the node displacement degrees of freedom in particular unit displacement, while the other node displacement are kept zero state of deformation, on all the nodes need to exert the node load. The advantages and disadvantages of the rectangular unit: the stress and strain of the displacement pattern are not constant, the distribution is closer to the distribution in the actual object, and the precision is improved. It is not easy to use different sizes of units in different parts for the differential of the bevel justification and curve What a