Maarten Blommaert

An automated approach to magnetic divertor configuration design

At present, several plasma boundary codes exist that attempt to describe the complex interactions in the divertor SOL (Scrape-Off Layer). The predictive capability of these edge codes is still very limited. Yet, in parallel to major efforts to mature edge codes, we face the design challenges for next step fusion devices. One of them is the design of the helium and heat exhaust system. In past automated design studies, results indicated large potential reductions in peak heat load by an increased magnetic flux divergence towards the target structures. In the present study, a free boundary magnetic equilibrium solver is included into the simulation chain to verify these tendencies. Additionally, we expanded the applicability of the automated design method by introducing advanced “adjoint” sensitivity computations. This method, inherited from airfoil shape optimization in aerodynamics, allows for a large number of design variables at no additional computational cost. Results are shown for a design application of the new WEST divertor.

Achievements and challenges in automated parameter, shape and topology optimization for divertor design

Plasma edge transport codes play a key role in the design of future divertor concepts. Their long simulation times in combination with a large number of control parameters turn the design into a challenging task. In aerodynamics and structural mechanics, adjoint-based optimization techniques have proven successful to tackle similar design challenges. This paper provides an overview of achievements and remaining challenges with these techniques for complex divertor design. It is shown how these developments pave the way for fast sensitivity analysis and improved design from different perspectives.

Optimization of Metal Fin Distributions in Latent Heat Storages

In this research, optimal fin distributions are presented for latent heat storages charged by a constant input power water flow. The limited input power results in non-uniform melting of the Phase Change Material (PCM). Therefore, new designs with non-uniform fin distributions provide the opportunity to outperform the ones with uniform distributions. In this paper, we show that different optimal fin distributions are found depending on the fin width, amount of fins and the input power. The gain in charging performance is discussed by comparing with latent heat storages without heat transfer enhancement.