STEP divertor swril tube concept design
UK
STEP (Spherical Tokamak for Energy Production) is an ambitious programme to deliver a prototype fusion energy plant, targeting 2040, and a path to commercial viability of fusion.
The programme is divided in three different phases. The aim for the first phase of is to produce a ‘concept design’ by 2024. This means an outline of the power plant, with a clear view on how each of the major systems will be designed.
One of these is the cooling system, that includes a swirl tape tube for cooling the STEP divertor target facing the plasma. This kind of tubes have an insert in the form of a tape for enhancing turbulence and, therefore, heat transfer.
The UKAEA (UK Atomic Energy Authority) asked IDOM to critically analyze the existing design and propose improvements thereto. The project consisted of a thermo-hydraulic analysis by means of CFD, and system code tools and a mechanical analysis and evaluation including manufacturing.
The current design was challenged by using a different turbulence enhancing geometry which can reach better performances and can be optimized to remove more heat from higher flux surfaces inside the pipes.
The final proposal was filed in a patent application as it is a novel concept for cooling this type of components under high heat flux.