Development of a Shattered Pellet Injector test bench for the ITER DMS support laboratory

Abstract

In the ITER Shattered Pellet Injection system large, Ø28.5x57mm cryogenic pellets have to be created and preserved in a barrel, until the control system detects a forthcoming disruption event and triggers the propellant gas valve to launch the pellet. The high-pressure propellant gas accelerates the pellet, which shatters on an angled plate near the edge of the plasma. The ablation of the resulting pellet fragments is intended to mitigate the consequences of the disruption and to prevent the generation of runaway electrons. To support the Shattered Pellet Injector technology for the ITER Disruption Mitigation System, a new support laboratory has been built at the Centre for Energy Research. The aim of the laboratory is to develop a test bench with ITER relevant dimensions, produce d=28.5mm Hydrogen, Neon and mixture pellets, observe the pellet acceleration and shattering with automated control. This contribution describes the cryogenic pellet injector of the test bench.