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Disruption Mitigation

The US will contribute 100% towards the disruption mitigation system (up to a capped value).

The system has two functions: 1) limiting the impacts of plasma current disruptions to the tokamak vacuum vessel, first wall blankets and other in-vessel components, and 2) suppressing the formation and deleterious effects of high energy runaway electrons. The mitigation and suppression are expected to be accomplished by rapid shattered pellet injection (SPI).For more information, contact:

For more information, contact David Rasmussen, US ITER Project Office Disruption Mitigation Team Leader, Oak Ridge National Laboratory, | 865-574-1158


Additional Resources:


Testbed for shattered pellet injection.

Perfecting the Pellet

ITER’s success will depend in part on subduing potential plasma instabilities. This ORNL team is tackling the challenge with shattered pellet injection.

KSTAR Tokamak

KSTAR joins an exclusive club: Tandem shattered pellet injectors now in testing for disruption mitigation

First-of-a-kind experiments have begun at the KSTAR tokamak in Daejeon, South Korea, where two new shattered pellet injectors were installed in October and December. The tandem use of shattered pellet injectors installed at opposite sides of the machine is a first for the technology, which was developed and fabricated at the Department of Energy’s Oak Ridge National Laboratory (ORNL).

Plasma discharge during shattered pellet injection testing on JET tokamak

First tests with JET's shattered pellet injector

The shattered pellet injector, which was installed and commissioned on JET over the last few months, is the result of an international collaboration between the ITER Organization, EUROfusion, US Department of Energy Fusion Energy Sciences, US ITER, and Oak Ridge National Laboratory (ORNL), with the project being centrally managed by the United Kingdom Atomic Energy Authority (UKAEA). "We are very excited to start testing," said Joe Milnes, the JET Operating Contract Senior Manager for the UKAEA. "The dedication shown by the project team, working through many nights and weekends to get the shattered pellet injector installed and commissioned, has been vital in getting to this point." "The JET Team is completely engaged in this process. They feel a sense of ownership of the ITER program," agreed Lorne Horton of the JET Exploitation Unit.

Source: ITER Newsline

Shattered pellet injection components on test stand at ORNL

Disruption mitigation shattered pellet injector gets ready for JET experiments

A shattered pellet injector (SPI) using the same technology as planned for the ITER disruption mitigation system has been installed on the JET tokamak at the Culham Centre for Fusion Energy in the UK and will be used in upcoming experiments.

Source: ITER Newsline

Drawing of injectors for disruption mitigation

Disruption Mitigation Task Force is Up to the Challenge

To face the challenge and to ensure that the ITER system will fulfil its purpose the ITER Disruption Mitigation Task Force has been established and an extensive program has been defined that focuses on refining system design specifications and on performing engineering work for industrialization of the technology.

Source: ITER Newsline

Plasma Disruptions Workshop Meeting March 2017

Workshop Discusses Plasma Disruptions

aAworkshop was jointly organized by ITER's Plant Engineering and Science & Operations departments to bring physics experts together with the US ITER engineers based at Oak Ridge National Laboratory (ORNL) developing the design of the disruption mitigation system. About 25 leading experts from the Members' fusion research centres and universities joined the intensive discussions.

Source: ITER Newsline