Stability and Dynamic Analysis of Parabolic Arch Structure Based on Finite Element Method
It presents the study on out-plane stability capacity of parabolic arch structure subjected to vertical uniform load and concentrated load by employing an elastic plastic large displacement finite element analysis.The full out-of-plane buckling load-displacement equilibrium path is theoretically investigated by using finite element approach in conjunction with the arc-length method.The transient dynamics of the space parabolic arch structure are analyzed by finite element method.The time-displacement curve is theoretically investigated with full method.The load analysis provides an effective method to analyze the stability and transient dynamics of parabolic arch structure,and the result provides an important basis for the study of the structural instability problems.
Radial distributions of Ar mass fractions and temperatures in plasmas produced in a wall-stabilized arc have been calculated. Modeling have been performed for many different mixtures of Ar+N2 and three different arc currents. The obtained results show that the radial distributions of Ar mass fractions strongly depend on the chemical composition of the plasma. In plasmas containing large amount of Ar the distributions have local minima at the arc axis (in high temperature plasma regions), whereas in plasmas consisting mainly of nitrogen the distributions reveal maxima on the discharge axis. Those features seem to be connected with the dissociation of the nitrogen.