Replicate the Ocean in the laboratory to develop technologies for the Sea
24 February 2022
Article by Diogo Neves, responsible for business development in the area of Technologies for the Sea
Numerical simulation and experimental modeling are fundamental tools in scientific and technological development, as they enable the reproduction of processes and solutions to real problems in a digital or controlled environment where all variables are measurable and/or controlled.
This capability is especially important in the development of technologies for the sea. Waves, currents, wind, sediment, and water temperature are some of the physical and environmental phenomena that we encounter in the marine environment, and to which equipment and structures with application in the renewable energy, naval and aquaculture sectors must adapt.
To this end, we study the real behavior of systems and processes in this environment with the application of simulation methods. Depending on the type of simulations, these must be accompanied by measurements, both numerically and experimentally, in order to obtain sufficient data for the comparison and understanding of the processes involved. By obtaining as much data as possible, we are able to make confident decisions regarding complex and difficult to perceive processes1.
Numerical simulation of transport of a GBS (Gravity Based Structure) by crane on a vessel.
"Advantages of using simulation methods are unquestionable"
Simulation methods have been used for a long time to predict future behavior, but only with the development of new technologies and instrumentation has it been possible to carry out simulations that expand the limits of scientific understanding 6, 12. In addition, for more than three decades3, the development of computing capacity has considerably reduced the cost associated with these processes.
Today, it's possible to simulate physical processes ranging from the most elementary particles to processes on an astronomical scale. This means that the advantages of using simulation methods are, nowadays, unquestionable.
At an industrial level, all product and process development is subject to a large number of tests, both at a computational and experimental level. However, any application of a simulation method or use of a computer simulation tool has to be accompanied by a high understanding of the scientific processes involved.
It is also considered that each simulation method should always be complemented through validation and application of complementary simulation methods 10. As an example, the development of a new mechanical device involves numerical simulation and experimental modeling tests at various scales, in order to validate and increase the degree of confidence in the results generated by the numerical simulations.
Different analysis methods for different stages of technological development
As part of the development of Technologies for the Sea, INEGI's specialists use advanced numerical simulation and experimental modeling methods in a laboratory and real environment to design and develop solutions tailored to the needs of the blue economy sector. Among the projects in our portfolio are the development of technologies related to marine renewable energies 2, 11, monitoring systems 4, 5, and the analysis of innovative propulsion systems9 related to mooring dynamics.
The development of products and systems suitable for the sea environment effectively requires the application of different simulation methods that meet the different stages of technological development (TRLs) 14, namely:
Numerical simulation methods
Numerical simulation methods are used at different stages of technological development, from concept development to the final product.
The characterization of the technology's operating location constitutes one of the fundamental phases for its development, through the application of numerical models of advection and transport 13 capable of creating a set of scenarios that can be modelled.
In a phase of project development and definition of the behavior of structures a sea environment, it is, in many cases, necessary to apply complex models that require high computational capacity, as is the case of CFD (Computational Fluid Dynamics) 4 models for simulation of flows and fields pressure gauges for the different phases of the system (TRL 3-4).
Subsequently, it is natural to evaluate the structural behavior through the application of finite element models (FEM - Finite Element Method), in order to evaluate its limit states and modes of operation, considering the type of material of the structure under development. This last phase of numerical modeling of the structural behavior enables the scale test phase for validation in a relevant experimental environment (TRL 5).
Experimental modeling methods
On the other hand, the behavior of a structure can be modeled through experimental methodologies in a relevant environment, such as tank that allows the simulation of realistic scenarios at scale8.
There are methodologies and infrastructure suitable for each type of scenario to be simulated - be it long towing tanks7 to simulate the hydrodynamic conditions of vessels, low depth tanks for technologies applied to coastal structures, high depth tanks for simulating the behavior of offshore structures, and even 2D wave channels for the evaluation of the 2D behavior of structures. Even so, for marine technologies it's usually key to carry out tests at sea for an extended period of time to validate of the technology6 (TRL > 6).
This type of integrated approach, applied to different areas of knowledge, has an extremely relevant impact on obtaining adequate technical support to understand complex processes. An answer guaranteed by sea and naval engineering, for the development of technologies truly capable of meeting the challenges of the blue economy for a sustainable future.
References:
[1] - Bokor, Orsolya & Florez-Perez, Laura & Osborne, Allan & Gledson, Barry. (2019). Overview of construction simulation approaches to model construction processes. Organization, Technology and Management in Construction: an International Journal. 11. 1853-1861. 10.2478/otmcj-2018-0018.
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