Periodic Reporting for period 1 - ModConFlex (Modelling and control of flexible structures interacting with fluids)
Reporting period: 2023-02-01 to 2025-01-31
The ModConFlex (Modelling and Control of Flexible Structures Interacting with Fluids) project is centered around two main fields of application. The research provides theoretical foundations in two areas that can contribute to reach the European Green Deal objectives.
One application is the control of floating wind turbines. These are subject to various dynamic influences from water and air. Air is also referred to as fluid in the scientific context.
In 2020, the European Commission published a strategy on offshore wind energy, setting targets for at least 60 GW of offshore wind in 2030 and 300 GW in 2050. The regional offshore goals for 2030) even exceed the Commission goals by well over a third (86-89 GW by 2030). So far, floating wind turbines are in the minority here. Hence, there is still tremendous capacity for research on theoretical background as well as technological improvement to provide higher efficiency or even new functionality. The power of available instrumentation and digital processors is steadily increasing and it is often the theory and algorithm development that is lagging behind. Already now, offshore wind farms are capable of harvesting more frequent and stronger winds than onshore wind farms.
The second application are highly flexible aircraft, which are aircraft with a very high aspect ratio. The aspect ratio describes the shape of a plane's wing. When the aspect ratio is high, the wings are comparatively long and narrow, i.e. the plane has a large wingspan. Planes with a high aspect ratio require comparatively less fuel.
Some research results could also be applied to soft robotics.
At the background of these - at first glance quite different - applications, similar mathematical models are at work. Advances in the same mathematical theories can improve these models. Some of the project research focusses purely on the advancement of these mathematical theories, while others work on the improvement of the physical modelling underlying floating wind turbines or flexible aircraft.
In addition to contributing to the advancement of science, the ModConFlex project trains 14 researchers employed at eight universities in five countries in state-of-the-art scientific techniques in mathematics and/or engineering.
Via secondments at other universities and participation in international conferences, the researchers' training benefits from an international network and the dissemination of their research. Secondments at industrial partners additionally provide them with an insight into research outside of academia and improve their understanding of the practical application of research.
The project researchers are employed at Bergische Universität Wuppertal (D), Université de Bordeaux (F), Université Marie et Louis Pasteur (F), Friedrich-Alexander-Universität Erlangen-Nürnberg (D), Imperial College of Science, Technology and Medicine (GB), Tel Aviv University (IL), Universiteit Twente (NL), and University of Warwick (GB).
One application is the control of floating wind turbines. These are subject to various dynamic influences from water and air. Air is also referred to as fluid in the scientific context.
In 2020, the European Commission published a strategy on offshore wind energy, setting targets for at least 60 GW of offshore wind in 2030 and 300 GW in 2050. The regional offshore goals for 2030) even exceed the Commission goals by well over a third (86-89 GW by 2030). So far, floating wind turbines are in the minority here. Hence, there is still tremendous capacity for research on theoretical background as well as technological improvement to provide higher efficiency or even new functionality. The power of available instrumentation and digital processors is steadily increasing and it is often the theory and algorithm development that is lagging behind. Already now, offshore wind farms are capable of harvesting more frequent and stronger winds than onshore wind farms.
The second application are highly flexible aircraft, which are aircraft with a very high aspect ratio. The aspect ratio describes the shape of a plane's wing. When the aspect ratio is high, the wings are comparatively long and narrow, i.e. the plane has a large wingspan. Planes with a high aspect ratio require comparatively less fuel.
Some research results could also be applied to soft robotics.
At the background of these - at first glance quite different - applications, similar mathematical models are at work. Advances in the same mathematical theories can improve these models. Some of the project research focusses purely on the advancement of these mathematical theories, while others work on the improvement of the physical modelling underlying floating wind turbines or flexible aircraft.
In addition to contributing to the advancement of science, the ModConFlex project trains 14 researchers employed at eight universities in five countries in state-of-the-art scientific techniques in mathematics and/or engineering.
Via secondments at other universities and participation in international conferences, the researchers' training benefits from an international network and the dissemination of their research. Secondments at industrial partners additionally provide them with an insight into research outside of academia and improve their understanding of the practical application of research.
The project researchers are employed at Bergische Universität Wuppertal (D), Université de Bordeaux (F), Université Marie et Louis Pasteur (F), Friedrich-Alexander-Universität Erlangen-Nürnberg (D), Imperial College of Science, Technology and Medicine (GB), Tel Aviv University (IL), Universiteit Twente (NL), and University of Warwick (GB).
The research conducted by the researchers can be attributed to three main fields of mathematical theory. We have researchers working in artificial intelligence, mathematical and physical modelling.
A start has been made into research on improving mathematical modelling that is closely related to physical modelling (employed in more engineering related research). Also research on physical modelling and machine learning has progressed.
In mathematical modelling the combination of two different branches of mathematics resulted in a step towards numerical simulation of a theoretical model. Other mathematical research derived novel existence results for coupled mechanical structures, allowing to transfer existing theories to mechanical structures.
In physical modelling, a simple model has been constructed that describes the interaction of water waves with a floating model. This can be combined easily with a model that can then be used to analyse the stability of floating wind turbines.
One researcher is working with an associated partner on a power systems problem concerning floating wind turbines and has presented this research at a conference.
Another researcher has contributed to the understanding of modelling a complex system, simplifying it by connecting simpler blocks.
Research on a modular port-Hamiltonian model of a floating wind turbine has progressed, which will contribute to improve control strategies for offshore floating wind turbines, leading to safer implementation.
In the area of artificial intelligence / machine learning, a faster and more robust algorithm is being developed by one researcher, while another one developed rigorous foundations for machine learning models (transformers), which help to discover a small number of important features in a dataset.
The new methods utilise data from simulations and experiments in combination with optimization and machine learning algorithms to create accurate predictions and robust controllers to ensure their stable performance.
Another researcher created a new physics-informed data-driven modelling framework for nonlinear aeroelastic systems and showed that models created using the new technique outperform the best-known existing modelling approaches on a challenging flexible wing test-case.
A start has been made into research on improving mathematical modelling that is closely related to physical modelling (employed in more engineering related research). Also research on physical modelling and machine learning has progressed.
In mathematical modelling the combination of two different branches of mathematics resulted in a step towards numerical simulation of a theoretical model. Other mathematical research derived novel existence results for coupled mechanical structures, allowing to transfer existing theories to mechanical structures.
In physical modelling, a simple model has been constructed that describes the interaction of water waves with a floating model. This can be combined easily with a model that can then be used to analyse the stability of floating wind turbines.
One researcher is working with an associated partner on a power systems problem concerning floating wind turbines and has presented this research at a conference.
Another researcher has contributed to the understanding of modelling a complex system, simplifying it by connecting simpler blocks.
Research on a modular port-Hamiltonian model of a floating wind turbine has progressed, which will contribute to improve control strategies for offshore floating wind turbines, leading to safer implementation.
In the area of artificial intelligence / machine learning, a faster and more robust algorithm is being developed by one researcher, while another one developed rigorous foundations for machine learning models (transformers), which help to discover a small number of important features in a dataset.
The new methods utilise data from simulations and experiments in combination with optimization and machine learning algorithms to create accurate predictions and robust controllers to ensure their stable performance.
Another researcher created a new physics-informed data-driven modelling framework for nonlinear aeroelastic systems and showed that models created using the new technique outperform the best-known existing modelling approaches on a challenging flexible wing test-case.
Key points of novelty are expected in three main areas:
1. Modelling and Analysis
2. Controller Design
3. Various Engineering Applications
Topic one and two both focus on working with the adaptation/solution or possibly simplification of complex theoretical models that will facilitate their applicability to real world problems.
In the case of topic area one (Modelling and Analysis), the prime example of applicability, the modelling of a floating platform carrying wind turbines secured with mooring cables, has been a huge challenge to model so far.
Topic two (Controller Design) is concerned with developing powerful control design methods for the models resulting from Modelling and Analysis research, meaning that solutions to real world problems can be analysed in the models developed under topic one. The aim is to develop application tools for reducing unwanted vibrations in (interconnected) flexible structures in interactions with their environment. This could, for example, be oscillations of floating wind turbines caused by the fact that they are floating and be applied to ensure reliable power supply under various operating conditions:
The focus of topic three (Engineering Applications) is to apply techniques, partly those developed under the first two topics, to innovative engineering solutions. A representative example, apart from floating wind turbines, is the analysis of aircraft with high aspect ratio (long and slender) wings, which present the problem of experiencing large deformations. To analyse the dynamics of these is beyond the reach of traditional linear tools of control design. There is a lack of data-driven models that can describe the behaviour of aeroelastic systems in various operating conditions purely based on data samples. Project research addresses the problem of presently high computational cost of nonlinear simulation, e.g. finding a way to use only a small number a variables.
1. Modelling and Analysis
2. Controller Design
3. Various Engineering Applications
Topic one and two both focus on working with the adaptation/solution or possibly simplification of complex theoretical models that will facilitate their applicability to real world problems.
In the case of topic area one (Modelling and Analysis), the prime example of applicability, the modelling of a floating platform carrying wind turbines secured with mooring cables, has been a huge challenge to model so far.
Topic two (Controller Design) is concerned with developing powerful control design methods for the models resulting from Modelling and Analysis research, meaning that solutions to real world problems can be analysed in the models developed under topic one. The aim is to develop application tools for reducing unwanted vibrations in (interconnected) flexible structures in interactions with their environment. This could, for example, be oscillations of floating wind turbines caused by the fact that they are floating and be applied to ensure reliable power supply under various operating conditions:
The focus of topic three (Engineering Applications) is to apply techniques, partly those developed under the first two topics, to innovative engineering solutions. A representative example, apart from floating wind turbines, is the analysis of aircraft with high aspect ratio (long and slender) wings, which present the problem of experiencing large deformations. To analyse the dynamics of these is beyond the reach of traditional linear tools of control design. There is a lack of data-driven models that can describe the behaviour of aeroelastic systems in various operating conditions purely based on data samples. Project research addresses the problem of presently high computational cost of nonlinear simulation, e.g. finding a way to use only a small number a variables.