Progress at JET in integrating ITER-relevant core and edge plasmas within the constraints of an ITER-like wall

TLDR

The paper reports progress at JET‑ILW integrating ITER baseline scenario requirements with a normalized confinement factor of 1 and pressure of 1.8, achieving partially detached divertor operation over many energy confinement times. The study examines 2.5 MA high‑triangularity ELMy H‑modes using two divertor configurations (D‑gas injection and N seeding), investigating how increased energy confinement and pedestal pressure relate to triangularity, and mapping the operational space, ELM energy losses, and pedestal stability for seeded and unseeded plasmas. N seeding reduces power load, and the experiments achieved stationary plasma conditions over many energy confinement times.

Abstract

This paper reports the progress made at JET-ILW on integrating the requirements of the reference ITER baseline scenario with normalized confinement factor of 1, at a normalized pressure of 1.8 together with partially detached divertor whilst maintaining these conditions over many energy confinement times. The 2.5 MA high triangularity ELMy H-modes are studied with two different divertor configurations with D-gas injection and nitrogen seeding. The power load reduction with N seeding is reported. The relationship between an increase in energy confinement and pedestal pressure with triangularity is investigated. The operational space of both plasma configurations is studied together with the ELM energy losses and stability of the pedestal of unseeded and seeded plasmas. The achievement of stationary plasma conditions over many energy confinement times is also reported.