Modeling, Simulation and Optimization of a Polluted Water Pumping Process in Open Sea

Abstract: 

Oil spill contamination in open sea has provoked some of the
major environmental disaster in history. The ecological and economic
impacts of such hazards are generally important and should be controlled
as quickly as possible. One of the major cleaning techniques for these
hazards is the use of skimmer ships. Those ships use various pumps
distributed along the vessel perimeter to suck the oil from the surface of
the water directly into storage units.

In this work, we are interested in improving this process. To do so, we
first introduce a mathematical model to simulate the effect on the
evolution of given oil spill of: the diffusion, the transport by wind and
sea currents and the physical phenomena associated with the action of the
pumping ship, assuming that it follows a given trajectory. This model is
based on a split non-linear second order finite volume approximation of an
advection-diffusion-reaction equation.

In a second part, we design the trajectory of a skimmer ship in order to
minimize the amount of the remaining pollutant in the computational domain
after a given time. This problem is solved by considering a hybrid global
optimization method based on the combination of a particular Genetic
Algorithm (GA) and a Semi-Deterministic Secant Method to improve the GA
performance. This methodology is validated by considering various
numerical examples inspired from real hazards, such as the Prestige
accident (2002, Spain), and by comparing the obtained results with those
given by a classical GA. For each case, our algorithm has exhibited much
better results with significant improvements.

This work is joint with Susana Gomez (Universidad Nacional A. de Mexico,
Mexico), Angel Manuel Ramos (Universidad Complutense de Madrid, Spain) and
 Roland Glowinski (University of Houston, USA).

Posted on Jul 15, 2014 in Optimization and Equilibrium, Seminars