Session: 04-01-06 Flexible Pipes VI

Submission Number: 180979

An Optimisation Model for Umbilical Cable Design Considering Elements of Different Functions, Materials and Sizes With Possible Layering Restrictions 

One of the main tasks in umbilical cable design to provide functional, viable and
economic advantageous solutions concerns the definition of the distribution of
elements within the cross section of the cable. This task is commonly made in
an artisan way, relying on the know how of designers with many years of
experience, which may lead to difficulties on the fast response to pressing
demands for new solutions if the analyst does not have proper computational
aid for the task.
In recent years, different approaches have been proposed for the optimization
of the distribution of elements in the cross section of umbilical cables. However,
they mostly limit the analysis by forcing the internal elements to present the
same function or the same external diameter or sometimes limiting the range of
variability.
In the present work, an optimization model is developed to account for any type
of element and dimension introduced in the cross section, with the sole
limitation of all of them being externally circular. The algorithm is based on the
gradient optimization method, and it performs by solving the problem many
times with a random seed for the distribution of elements in the first step of
optimization and them comparing the different solutions obtained to verify which
presents the better result in terms of the proposed objective function. Such
comparison of a multitude of solutions allows for the combination of a
computationally fast optimization method with the possibility of avoiding the
trapping in local minima. In addition, the optimization model is equipped with
restriction functions that can account for the superposition of any two elements
within the cross section and the machinery limitation for the construction of the
cable regarding the maximum number of elements contained in a fabrication
layer.
The obtained model provides then an useful tool for the design of umbilical
cables, being able to generate different possibilities of design solutions within a
short time frame, which can then be investigated in detail by the user to address
which ones are suitable for actual fabrication and usage based on accumulated
experience.

Presenting Author: Guilherme Jorge Vernizzi Universidade de São Paulo

Presenting Author Biography: Dr Vernizzi holds a faculty position in the Department of Mechanical Engineering at the Escola Politécnica of the University of São Paulo. His research interests include nonlinear dynamics, fluid–structure interaction, and the behavior of slender and offshore structures under dynamic excitation. His main publications focus on structural dynamics and reduced-order modeling.

Authors:

Guilherme Jorge Vernizzi Universidade de São Paulo
Clóvis De Arruda Martins Universidade de São Paulo
Rodrigo Provasi Universidade de São Paulo
Rafael Giovane Morini PRYSMIAN CABOS E SISTEMAS DO BRASIL S.A.