ITER

ITER is an international engineering and research project oriented towards demonstrating the technical and scientific viability of fusion as an energy source. For general background information on the project, refer to the Wikipedia.

Main specifications

ITER is a magnetic confinement device of the tokamak type. The reference operational scenario is the ELMy H-mode with the following characteristic parameters:

ITER design

Parameter	Value
Major radius, R0 (m)	6.2
Minor radius, a (m)	2.0
Toroidal field at R0, BT (T)	5.3
Plasma current, Ip (MA)	15
Edge safety factor, q95	3.0
Confinement enhancement, HH98(y,2)	1.0
Normalised beta, βN	1.8
Average electron density, <ne> (1019m-3)	10.1
Fraction of Greenwald limit, <ne>/nGW	0.85
Average ion temperature, <Ti> (keV)	8.0
Average electron temperature, <Te> (keV)	8.8
Neutral beam power, PNB (MW)	33
RF power, PRF (MW)	7
Fusion power, Pfusion (MW)	400
Fusion gain, Q=Pfusion/(PNB+PRF)	10
Non inductive current fraction, INI/Ip (%)	28
Burn time (s)	400

In the standard scenario, part of the plasma current is inductively driven, so that operation is not steady state. Advanced scenarios seek to maximize pulse length by making use of the bootstrap current. This may be achieved, e.g., by creating Internal Transport Barriers.

Challenges

Organizational

• Multiparty coordination

Technical

• Avoidance and control of disruptions
• ELM mitigation
• Heat load handling in the divertor and on the wall
• Radiation handling and wall materials

Scientific

• Advanced operational scenarios (cf. Internal Transport Barrier)
• Alpha and energetic particle physics
• Diagnostic development

See also

• ITER website
• EFDA: ITER
• ITER Physics Basis, Nucl. Fusion 39, 12 (1999)