Modeling of Cables with High and Low Tension Zones using a Hybrid Rod-Catenary Formulation

TL;DR

This paper introduces a hybrid cable modeling approach combining rod and catenary models to efficiently simulate complex cable dynamics with localized low-tension zones, reducing computational costs while maintaining accuracy.

Contribution

A novel hybrid rod-catenary model that adaptively simulates high and low tension zones in cables, improving efficiency and accuracy over traditional models.

Findings

Hybrid model accurately captures flexure and torsion in low-tension zones.

Significantly reduces computational effort compared to full rod models.

Effective for large-scale cable simulations with mixed tension zones.

Abstract

Cables under very low tension may become highly contorted and form loops, tangles, knots and kinks. These nonlinear deformations, which are dominated by flexure and torsion, pose serious concerns for cable deployment. Simulation of the three-dimensional nonlinear dynamics of loop and tangle formation requires a 12th order rod model and the computational effort increases rapidly with increasing cable length and integration time. However, marine cable applications which result in local zones of low-tension very frequently involve large zones of high-tension where the effects of flexure and torsion are insignificant. Simulation of the three-dimensional dynamics of high-tension cables requires only a 6th order catenary model which significantly reduces computational effort relative to a rod model. We propose herein a hybrid computational cable model that employs computationally efficient catenary elements in high-tension zones and rod elements in localized low-tension zones to capture flexure and torsion precisely where needed.