To discover the nonlinear characteristics of pipe flow, we simulated the flow as a sum of many vortex rings. As a first step, we investigated the nonlinear interaction among a maximum of three vortex rings. The pipe wall was replaced by many bound vortices. A free vortex ring moves right or left according to the radius, and that of a particular radius keeps the initial position. The energy of a...

Pipe-in-pipe structure are widely used in offshore oil and gas transportation. The is subjected to various dynamic loads such as earthquakes vortex-induced vibrations during service, of which transverse impact the main cause damage. At present, whole process analysis parameter pipe-in-pipe under action not systematic complete. Based on explicit software LS-DYNA, finite element model was establi...

One of the solutions of the Helmholtz equation is the vortex beams. In the recent decades, production and applications of these types of beams have found serious attentions. Determination of the vortex beam topological charge and its sign are very important issues. Odd number of reflections of the vortex beam changes its vorticity. In this paper, we have used a q-plate to generate a vortex beam...