Finit element model of pipeline discretization by prismatic elements

Abstract

Using the shells of triangular finite elements in calculations with a choice of nodal unknowns in the displacements form and their first derivatives, the continuity between the elements is provided only by displacements. Continuity in the derivative values is performed only at the nodal points and is absent at the boundaries between the elements. This circumstance often leads to a very slow convergence of the computational process. In this article, when using a prismatic finite element with a triangular base, improvement of the computational process by ensuring the equality condition of the derivatives normal displacements in the sides middle of adjacent triangular bases using uncertain Lagrange multipliers. Correctness and efficiency of the developed algorithm are shown in terms of the calculation.