Compacted wire strand is produced by applying compression to the readymade classical wire strand. Therefore, parametric mathematical curves that can create geometric cross-sectional shape of the center and outer wires are not available. The center and outer wires of compacted wire strand are formed with the help of the real cross-sectional compacted wire rope by using the developed computer code. Due to the compaction process cross-sections of the core wire and the outer single helical wires of the circular wire strand becomes to hexagonal and isosceles trapezoidal shapes respectively. The amount of gap in the cross-sectional area is decreased and the contact surfaces of the wires are increased by compaction process. As a result, the diameter of the compacted wire strand is decreased at the end of this process. After the modeling process, a finite element analysis is conducted by applying strain boundary condition to the compacted wire strand. The obtained results are compared with the analytical, test and the finite element analysis results obtained for the classical wire strand model and the good agreement between them is recognized. Meanwhile the analysis results showed that the contact forces are decreased due to the increased contact area between the outer wires of the compacted wire strand. This also proves that the compaction process increases the strength and life span of wire strands.

Computational Design of the Compacted Wire Strand Model and Its Behavior Under Axial Elongation

Curvilinear lines and surfaces are common geometrical objects in both structured and unstructured grid generation techniques. Curves appear in grid considerations as the boundary segments of two-dimensional domains or surface patches and as the edges of three-dimensional blocks. Surfaces arise as the boundary segments and/or faces of three-dimensional domains or blocks.

Curve and Surface Grid Methods

An elliptic grid generation method is presented which generates excellent boundary conforming grids in domains in 2D physical space. The method is based on the composition of an algebraic and elliptic transformation. The composite mapping obeys the familiar Poisson grid generation system with control functions specified by the algebraic transformation. New expressions are given for the control functions. Grid orthogonality at the boundary is achieved by modification of the algebraic transformation. It is shown that grid generation on a minimal surface in 3D physical space is in fact equivalent to grid generation in a domain in 2D physical space. A second elliptic grid generation method is presented which generates excellent boundary conforming grids on smooth surfaces. It is assumed that the surfaces are parametrized and that the grid only depends on the shape of the surface and is independent of the parametrization. Concerning surface modeling, it is shown that bicubic Hermite interpolation is an excellent method to generate a smooth surface which is passing through a given discrete set of control points. In contrast to bicubic spline interpolation, there is extra freedom to model the tangent and twist vectors such that spurious oscillations are prevented.

https://ntrs.nasa.gov/api/citations/19950022339/downloads/19950022339.pdf

S. P. Spekreijse

Papers

Elliptic surface grid generation on minimal and parmetrized surfaces