This paper presents a comparison of numerical methods used to model large scale acoustic coupled fluidstructure interaction (FSI) problems for single and double-walled cylindrical shells. The finite element method (FEM) is used to model the structure while the fast multipole boundary element method (FMBEM) is used to model the fluid domain and both models are coupled on the shared boundary surf...

We present an algorithm for constructing families of conforming (i.e. face-to-face) nonobtuse tetrahedral finite element meshes for convex 3D cylindrical-type domains. In fact, the algorithm produces only path-tetrahedra.

Composite stiffened cylindrical shells are widely used as primary elements in aerospace structures. In the recent years, there has been a growing research interest in optimum design of composite stiffened cylindrical shell structures for stability under buckling load.  This paper focuses upon the development of an efficient optimization of ring-stringer stiffened cylindrical shell. The opti...

OBJECTIVE The purpose of this study was to analyze stress distributions in the roots, periodontal ligaments (PDLs), and bones around cylindrical and tapered miniscrews inserted at different angles using a finite element analysis. METHODS We created a three-dimensional (3D) maxilla model of a dentition with extracted first premolars and used 2 types of miniscrews (tapered and cylindrical) with...

This paper introduces a novel feeding technique aimed for increasing the bandwidth of a patch antenna. It is shown that by using two 180 degrees out of phase excited cylindrical probes, the bandwidth of a patch antenna can be dramatically increased. Based on the proposed differential cylindrical probes (DCP) feed, we designed a square patch antenna with 104% impedance bandwidth for VSWR<2:1. Th...

A finite element program capable of analysing finite plane strain deformations of incompressible rubberlike (Mooney-Rivlin) materials has been develop~d. Two problems, namely a long wall loaded uniformly in two directions and a thick-wall cylindrical pressure vessel loaded internally, have been solved. The computed values of displacements, strains, stresses and hydrostatic pressure agree very c...

A highly optimized simulated annealing (SA) algorithm is applied to reconstruct permittivity images of real two-phase gasoil flows through a cylindrical vessel using electrical capacitance tomography (ECT). ECT yields low-accuracy images but is robust, inexpensive and much faster than many other tomography processes. This non-intrusive method essentially measures nonconductive system distributi...

The response of a neo-Hookean fiber composite undergoing finite out-of-plane shear deformation is examined. To this end an explicit close form solution for the out-of-plane shear response of a cylindrical composite element is introduced. We find that the overall response of the cylindrical composite element can be characterized by a fictitious homogeneous neo-Hookean material. Accordingly, this...

This paper presents an exact solution and a finite element method (FEM) for a Piezoceramic Rod under static load. The cylindrical rod is made from polarized ceramics (piezoceramics) with axial poling. The lateral surface of the rod is traction-free and is unelectroded. The two end faces are under a uniform normal traction. Electrically, the two end faces are electroded with a circuit between th...