Analytical Solution of the Drive Vibration With Time Varying Parameters

The paper deals with an approach to the analytical solution of the periodical vibration of mechanical systems with n DOF esspecially drives containing periodically varying parameters (e.g. stiffnesses). The model is described by means of the Fredholm’s matrix integral equation with degenerated kernel and a periodical Green’s function is used for the solution. The application can be shown e.g. on the Cardan’s mechanism and gear transmission having the time varying tooth stiffnesses. The result correctness is validated by means of Runge-Kutta integration method.

Influence of Ice Covering on Stiffness of Tower Components

In the icing electric transmission tower computation, has neglected the influence of ice stiffness and geometric effect to the iron tower component's stiffness. In the heavy ice area, such simplification is possibly inappropriate. Base on the parallel principle, proposed the ice-coated compression bar flexural stiffness formula, and proofed result correctness through finite element computation. Took the circular solid section and circular tuber section ice-coated tower components for example, ice-coated tower components were equivalent to compound materials in heavy ice area. Under certain load condition, compared the deflection and stiffness of tower component covered the different thickness ice, which took the line load with equivalent to the compound materials. Result showed that in the heavy ice area, the ice geometry effect has increased the tower component stiffness. The influence is more obvious to the tower stiffness than its dead-weight.