# industry

## Helical Strand Mechanics Modelling

Some 2014 papers on the mechanics of helical strands: cables and electrical conductors

## Cable FEA modelling

A 2014 paper on cable FEA modelling

## An early stick-slip model for cable bending analysis

One approach to helical strand (cable or overhead electrical conductor) bending analysis puts the emphasis on friction rather than on elastic curved rod behavior. Based on Coulomb’s laws of friction, it leads to stick-slip models where strand  bending stiffness varies with imposed curvature (Papailiou, 1995). Such an approach can be traced back to a Ph.D. thesis by H. Ernst, in 1933. This work is in fact often referred to in cable analysis reports. An English translation (with a short presentation) of the dissertation analytical part is attached.

## Vibrations

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How to do a frequency sine sweep in abaqus CAE. I want to get a frequency response curve (mises stress,U) through applying a forcing function on a turbine disc to estimate stresess at resonating conditions.

## Helical Strand in Bending

Several approaches have been used to deal with the complex problem of helical strands in bending. One of them is based on Love’s curved rods theory. It has first been used by Costello in his classical monograph “Theory of Wire Rope”. It has been extended by Sathikh et al. in several papers. A new contribution from this group is a Ph.D. Thesis by D. Gopinath : “Some studies on bending response of the stranded cable under free bending and constrained bending”, Anna University, Chennai (India), October 2013, 121 pages.

## Justification for use of Riks method to investigate gross plastic deformation

Hi, my question is on the use of Riks and other Arc length methods when analysing  a system for gross plastic deformation. ASME B&PV code , in its investigation for Gross plastic deformation as a Load at which convergence does not take place. Now, as far as I understand, Newton Raphson method fails at locations of singularity in the stiffness matrix and also at Bifurcation points, it can trace the unstable primary paths. Both these issues can be overcome ( provided the limit point is not too sharp) by Riks and other Arc length methods.

## CABLE BENDING ANALYSIS THOUGH FEA

Single strand cable (spiral) bending and OEC (Overhead Electrical Conductor) bending are somewhat similar problems. This is the reason why the following new paper is noteworthy within the context of this blog. It emanates from a Slovak team: S. Kmet, E. Stanova, G. Fedorko, M. Fabian, J. Brodniansky. Title : “Experimental investigation and finite element analysis of a four-layered spiral strand bent over a curved support”. Published in “Engineering Structures”, Vol. 57, December 2013, pp. 475-483.

## Simulation Thermal Mechanics of PCB with Vias Using Ansys

Hi, I am new to this blog & asking for help from you! If any one know that Ansys has 3D composite element that we can use to simulate PCB with Metal Vias (In-plan Fiber glass & epoxy & Out of Plan Metal Cylinders. Tx

## Failure Criteria

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Hello Friends,

I am struggling to correlate FEA results with experimental
results. I work on polymer parts reinforced with glass fibers. I have stress
strain curves for the material till failure. My FEA results are 50% off from
the experimental results. The model is setup correctly.

## Bending of cables : a stick-slip model

Bending of cables and, for that matter, of any helical strand system (such as overhead electrical conductors) is a challenging solid mechanics problem, with geometry and multibody frictional contact aspects. As seen in several recent papers, one workable approach is based on Coulomb’s laws of friction.  An earlier contribution by Lehanneur (1949), published in French, has generally been  ignored. The attached report presents a translation into English (including a presentation) of this most interesting work.

## J Integral calculation for an Axisymmetric Problem with crack in Ansys

Hi all,

I am working on Crack growth analysis of Turbocharger wheel and shaft assembly. I have simulated it as an axisymmetric problem with fine mesh around the cracktip(in Ansys). Element used is Plane182.

I have to compare the K1 and K2 values obtained from both the Displacement Extrapolation Method and J-Interal method.

I got the K1 an K2 values at the cracktip location by defining path using displacement extrapolation method.

But, I was not able to get the Stress intensity factor values (K1 nad K2) using J-Integral Method.

## Dynamic force on a closing mitre gate

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I'm looking at the design forces acting on a vertically hinged mitre gate for flow control in a canal, (open channel flow).  We know the maximum volumetric flow rate of the water flow when the gate is closing.  How can I estimate the maximum force exerted on the gate as the water causes it to slam shut.

## Overhead Electrical Conductors and High Intensity Wind

Effect of tornadoes on electrical power lines has been discussed by Sébastien Langlois in his M.Eng. thesis : “Design of Overhead Transmission Lines subject to Localized High Intensity Wind”. McGill University, Montreal, QC, Canada, 2007 (available on-line on the “Theses Canada” portal). Work presents various national and international standards (ASCE, Cigré, IEC etc.), historical cases, as well as models for numerical simulation.

## Aeolian vibrations and fatigue of Overhead Electrical Conductors

An interesting presentation of the state of the question by  Dr Louis Cloutier, in 2008.

## A case of conductor fatigue

As a follow-up, here is a photograph of a (rather extreme) case of conductor fatigue.

## link 8, introduced tensile curve and compression curve

Hi.

I'm working  with the element link8 (Ansys 12.1) and I have to introduced the tensile curve and compression curve, but I don't know, How I have to introduced its???

I have worked with the comands: TB: aniso, miso,..., I think the best option is: TB, user, but How I have to introduced the values of tensile and compression curve?, when this are different.

File attachment is the tensile and compression curve to introduce

Thank you, Toni

## Surface Boundary Measurement Using 3D Profilometry

In profilometer studies where the interface of surface features, patterns, shapes etc., are being evaluated for orientation, it will be useful to quickly identify areas of interest over the entire profile of measurement. By segmenting a surface into significant areas the user can quickly evaluate boundaries, peaks, pits, areas, volumes and many others to understand their functional role in the entire surface profile under study.