J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

Report on: WP10-PWI-01-01-01/IPP/PSMulti machine scaling of fuel retention for ITER

• Validation of the assessment procedure for inventories from the underlying retention processes for different tokamaks, such as ASDEX Upgrade, Tore Supra and JET.

• Extension of the multi machine scaling of fuel retention to ITER (AUG, TS, TEXTOR (JET for comparison), other relevant devices, PSI devices).

ASDEX UpgradeJ. Roth, M. Mayer, K. Sugiyama, K. Krieger, V. Rohde, A. Kallenbach,

Tore SupraE. Tsitrone, C. Brosset, T. Dittmar, E. Gauthier, T. Loarer, J. Bucalossi

TEXTOR V. Philipps, S. Brezinsek, A. Kirschner, A. Litnovsky,

PISCESR. Doerner, M. Baldwin

• Benchmark predictions for Carbon against present day tokamaks

• Validate methodology for all-W ASDEX Upgrade

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

First part:

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

(for comparison)

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

for carbon PFCs

(particle balance)

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

Fuel retention in all-W machines

• Only one machine available for validation of methodology: AUG

• Particle balance from literature:(V. Rohde, NF 49(2009)085031)

long term retention 4% of injectedabout 2 ± 1.5 g/hIntegration over 30 dischargescompared with 23% in all carbon

• Post-mortem results in dominantly divertor retention of 0.2 ± 0.1 g/h

(K. Sugiyama, NF 50(2010)035001

• Retention reduced by about a factor of 10

Flu

xe

s (

at/

s)

Inv

en

tory

(a

t)

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

all-W AUG

gas balance

post-mortem

all-carbon AUG

Fuel retention in all-W machines

• Only one machine available for validation of methodology: AUG

• Particle balance from literature:(V. Rohde, NF 49(2009)085031)

long term retention 4% of injectedabout 2 ± 1.5 g/hIntegration over 30 dischargescompared with 23% in all carbon

• Post-mortem results in dominantly divertor retention of 0.2 ± 0.1 g/h

(K. Sugiyama, NF 50(2010)035001

• Retention reduced by about a factor of 10

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

Crucial input data for scaling

• fluxes to PFCs (see above)• retention data vs. temperature, energy,

fluence• Is there good evidence for retention saturation?

30 g

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

Simple scaling from AUG to ITER

• using fluxes to PFCs (see above)

• Reasonable agreement with post-mortem data

• For one hour almost linear increase in retention with PFC flux both, for all carbon and all W

• Wall retention determines ITER inventory after long times. For one

hour no saturation yet for ITER retention.

AUG ITER

all carbon

all W

flux

J. Roth, EU PWI TF, SEWG Fuel Retention, Garching, July 19, 2010

Conclusion for W PFCs

• scaling methodology benchmarked for all-W ASDEX Upgrade• reasonable agreement within error bars for post-mortem campaign

inventory• gas balance depends strongly on particular discharge, inventory assessment requires long (>45 s) integration times•Extrapolation to ITER: 1-3 g T in first hour, non linear,

saturation below 50 g T total• Next step: benchmark for W and Be: JET ILW

Status report, evaluations ongoing

Discussion

• data ranges covers fluences expected for the ITER wall lifetime

• non-linear increase with time (α t1/2)• saturation at high fluences

• additional effects due to n-damage needs to be assessed

α t1/2

saturation