# Numerical Simulation of a Three-dimensional Subsea Cable with Buoyancy Module

## Authors

• Nur Adlin Lina Normisyidi Department of Structure and Material, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia
• Ahmad Razin Zainal Abidin Department of Structure and Material, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia
• Yeak Su Hoe bDepartment of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia

## Keywords:

Subsea cable, Buoyancy module, Dynamic model

## Abstract

Extreme formation of slacks and entanglement with risers induced from a small diameter and high structural flexibility of subsea cable is often being a huge challenge in subsea cable installation. In many cases, the cable is prone to breaking, bending, or twisting due to the rough and dynamic underwater condition. One of the alternatives is the use of buoyancy module to facilitate the cable installation and to reduce cable tension and false slacks. This paper proposes reliable three-dimensional mathematical model and simulation to specifically investigate the behaviour of subsea cable with buoyancy module during laying operation. A finite difference method (FDM) and optimization algorithm is used to discretize the formulation and simulate this type of subsea cable problem concerning on the tensional analysis. The methodology is specifically designed to allow cable configuration to be changed over time as a result from the buoyancy module. The viability subsea cable configuration with existence of buoyancy module has been showed successfully reduce the cable tension especially at the hang-off section.

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