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In this paper, a linear mathematical and numerical model for analysing the dynamic response of a flexible electroactive wave energy converter is described. The Wave Energy Converter (WEC) is a floating elastic tube filled with slightly pressurised sea water. It is made of Electroactive Polymers (EAPs).Under simplifying assumptions, a set of governing equations is formulated for the flow inside the tube, the flow outside the tube and the behaviour of the tube wall. By combining them, the evolution of the flow velocity in the tube can be written as a wave equation. The corresponding eigenmodes of vibration are calculated. Then, using spectral decomposition, the equation of motion for the response of the tube in waves is derived. Experiments were carried out on a scale model of the wave energy converter in the wave tank of Ecole Centrale de Nantes in 2011. Numerical results are compared with experimental results in regular waves, showing rather good agreement, which validates the model and the initial modelling assumptions. Finally, estimates are made for the energy performance of a possible prototype.

In this paper, a linear mathematical and numerical model for analysing the dynamic response of a flexible electroactive wave energy converter is described. The Wave Energy Converter (WEC) is a floating elastic tube filled with slightly pressurised sea water. It is made of Electroactive Polymers (EAPs).Under simplifying assumptions, a set of governing equations is formulated for the flow inside the tube, the flow outside the tube and the behaviour of the tube wall. By combining them, the evolution of the flow velocity in the tube can be written as a wave equation. The corresponding eigenmodes of vibration are calculated. Then, using spectral decomposition, the equation of motion for the response of the tube in waves is derived. Experiments were carried out on a scale model of the wave energy converter in the wave tank of Ecole Centrale de Nantes in 2011. Numerical results are compared with experimental results in regular waves, showing rather good agreement, which validates the model and the initial modelling assumptions. Finally, estimates are made for the energy performance of a possible prototype.

Owing to the complexity of the sector, industrial activities are often represented with limited technological resolution in integrated energy system models. In this study, we enriched the technological description of industrial activities in the integrated energy system analysis optimisation (IESA-Opt) model, a peer-reviewed energy system optimisation model that can simultaneously provide optimal capacity planning for the hourly operation of all integrated sectors. We used this enriched model to analyse the industrial decarbonisation of the Netherlands for four key activities: high-value chemicals, hydrocarbons, ammonia, and steel production. The analyses performed comprised 1) exploring optimality in a reference scenario; 2) exploring the feasibility and implications of four extreme industrial cases with different technological archetypes, namely a bio-based industry, a hydrogen-based industry, a fully electrified industry, and retrofitting of current assets into carbon capture utilisation and storage; and 3) performing sensitivity analyses on key topics such as imported biomass, hydrogen, and natural gas prices, carbon storage potentials, technological learning, and the demand for olefins. The results of this study show that it is feasible for the energy system to have a fully bio-based, hydrogen-based, fully electrified, and retrofitted industry to achieve full decarbonisation while allowing for an optimal technological mix to yield at least a 10% cheaper transition. We also show that owing to the high predominance of the fuel component in the levelled cost of industrial products, substantial reductions in overnight investment costs of green technologies have a limited effect on their adoption. Finally, we reveal that based on the current (2022) energy prices, the energy transition is cost-effective, and fossil fuels can be fully displaced from industry and the national mix by 2050.

Owing to the complexity of the sector, industrial activities are often represented with limited technological resolution in integrated energy system models. In this study, we enriched the technological description of industrial activities in the integrated energy system analysis optimisation (IESA-Opt) model, a peer-reviewed energy system optimisation model that can simultaneously provide optimal capacity planning for the hourly operation of all integrated sectors. We used this enriched model to analyse the industrial decarbonisation of the Netherlands for four key activities: high-value chemicals, hydrocarbons, ammonia, and steel production. The analyses performed comprised 1) exploring optimality in a reference scenario; 2) exploring the feasibility and implications of four extreme industrial cases with different technological archetypes, namely a bio-based industry, a hydrogen-based industry, a fully electrified industry, and retrofitting of current assets into carbon capture utilisation and storage; and 3) performing sensitivity analyses on key topics such as imported biomass, hydrogen, and natural gas prices, carbon storage potentials, technological learning, and the demand for olefins. The results of this study show that it is feasible for the energy system to have a fully bio-based, hydrogen-based, fully electrified, and retrofitted industry to achieve full decarbonisation while allowing for an optimal technological mix to yield at least a 10% cheaper transition. We also show that owing to the high predominance of the fuel component in the levelled cost of industrial products, substantial reductions in overnight investment costs of green technologies have a limited effect on their adoption. Finally, we reveal that based on the current (2022) energy prices, the energy transition is cost-effective, and fossil fuels can be fully displaced from industry and the national mix by 2050.

In old age, the complex relation of food consumption with energy and nutrient requirements finds expression in both single and multiple nutritional problems. Addressing conditions affecting intake -- either from foods or from supplements -- endogenous production, bioefficacy and/or requirements can benefit nutritional health in old age through balancing requirements and supply.

In old age, the complex relation of food consumption with energy and nutrient requirements finds expression in both single and multiple nutritional problems. Addressing conditions affecting intake -- either from foods or from supplements -- endogenous production, bioefficacy and/or requirements can benefit nutritional health in old age through balancing requirements and supply.

Comparative wind tunnel experiments were performed on passive flow separation control on a at plate model equipped with a flap. The purpose of these tests was to investigate the flow control capabilities of off-surface mounted elements. A comparison was made of delta-shaped vortex generators of 1 to 1/3 boundary layer height and cylinders close to the wall. Surface pressure as well as PIV measurements were performed to investigate the influence of the layout of the VGs as well as the diameter of the cylinder and the position of the elements. The results showed that the off-surface devices performed better than the on-surface VGs for the fully separated case, and were equally good in improving the state of boundary layer that is on the verge of separation. It was also found that the off-surface devices could be positioned over a wider range with respect to the separation point. The experiments furthermore indicated that for the optimum cylinder configuration the vortex shedding frequency was consistent with the frequencies found in literature on periodic flow excitation.