ERO code development

ERO code development

A. Kirschner

M. Airila, D. Borodin, S. Droste, C. Niehoff

The ERO code

ERO code management

Modelling of CH4 puffing in ASDEX

Modelling of CH4 puffing in JET

The ERO code

3-dimensional (at present 2D for divertor), Monte Carlo

Various experimental geometries are possible(at the moment: TEXTOR, ASDEX, JET, ITER, PISCES, MAGNUM)

Plasma-wall-interaction:

- physical sputtering, chemical erosion (CH4 or higher hydrocarbons)

- C-deposition from background, re-deposition of eroded particles Local particle transport:

- ionisation, recombination, dissociation

- Ehrhardt/Langer or Janev data for CH4 reaction chain

- friction (Fokker-Planck), thermal force, Lorentz force, diffusion D

ERO code management (1)

Several users and developers: version controlling necessary

CVS (Concurrent Versions System) – server at FZJ

Variety of versions

ERO.LIM

ERO.DIV

ERO.LINEAR

“Main line of

development”CVS parallelisation

ERO code management (2)

Development of user friendly interface (“JERO”)

in combination with ERO internet webpage

Modelling of 13CH4 puffing in ASDEX (1)

-1.2

-1.1

-1

-0.9

-0.8

-0.7

-0.6

-0.5

1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9

R [m]

Z [m]

ERO simulationvolume

80° rotation

B2-Eirene grid of divertor region

ERO simulation volume (outer divertor):

0

40

80

120

160

-160 -120 -80 -40 0 40 80 120 160

distance along outer target [mm]

r [m

m]

separatrix



Plasma parameter (L mode) from B2-Eirene (D. Coster)

separatrix


CH4 CH2 CH

CH+ C C+

0 80 mm

80mm

0CH4

Transport of injected CH4 into outer divertor @ s=48mm:

sticking assumption for hydrocarbons S = 0

C-Deposition from injected CH4 (@ 48mm) into outer divertor:

sticking assumption for hydrocarbons S = 0

local deposition: ~70%, losses to PFR: ~30%

0

0.2

0.4

0.6

0.8

1

-160 -120 -80 -40 0 40 80 120 160

distance along outer plate [mm]

de

po

sit

ion

[a

.u

.]

PFR

SEP

SOL



Injection of CH4 (@ 48mm and 88mm) into outer divertor:

Puff @ 48 mm Puff @ 88 mm

S = 0 S = 1 S = 0 S = 1

Deposition at target 70% 96% 89% 99.4%

Puffing location deeper in SOL: high local re-deposition even if with S = 0!!!

Further 13C transport modelling in ASDEX:

in co-operation with M. Airila

(Helsinki University of Technology)


Modelling of CH4 puffing in JET (1)

MkIIA: Standard gas fuelled ELMy H-mode, 12 MW (#44029)

ne [cm-3]

240230 250 260220

-170

-160

-150

-140

-130

-180

RC [cm]

ZC [cm]

240230 250 260220

-170

-160

-150

-140

-130

-180

RC [cm]

ZC [cm] Te [eV]

• Zero sticking of hydrocarbons CDy, Ehrhardt-Langer• Location of injection: strike point

Profiles of re-deposition for various incoming ion fluxes:

Amount ofre-deposition:

88%

89%

87%

vertical plate

base plate

0.0E+00

2.0E+12

4.0E+12

6.0E+12

8.0E+12

1.0E+13

1.2E+13

0 50 100 150 200 250 300 350 400x along plates [mm]

par

ticl

es/a

rea

[a.u

.] (0.5ne, 2Te)

(ne, Te)

(2ne, 0.5Te)



Amount ofre-deposition:

76%

72%

66%

0.0E+00

1.0E+12

2.0E+12

3.0E+12

4.0E+12

5.0E+12

0 50 100 150 200 250 300 350 400x along plates [mm]

par

ticl

es/a

rea

[a.u

.] (0.5ne, 2Te)

(ne, Te)

(2ne, 0.5Te)

vertical plate

base plate

• Zero sticking of hydrocarbons CDy, Ehrhardt-Langer• Location of injection: center of base plate (SOL)

Profiles of re-deposition for various incoming ion fluxes:

Summary: re-deposition of injected CD4 and C2D4

Injection at strike point: Injection at center of base plate (SOL):

0

20

40

60

80

100

0.5 0.75 1 1.25 1.5Incoming Ion Flux [a.u.]

amo

un

t [%

]

0

20

40

60

80

100

CD4

C2D4

(0.5ne / 2Te) (ne / Te) (2ne / 0.5Te)

0

20

40

60

80

100

0.5 0.75 1 1.25 1.5Incoming Ion Flux [a.u.]

0

20

40

60

80

100

CD4

C2D4

(0.5ne / 2Te)(2ne / 0.5Te)(ne / Te)

• No significant difference in re-deposition of puffed CD4 and C2D4

• Puffing at strike point: no significant dependence on flux

• Puffing at center of base plate (SOL): decreasing re-deposition with increasing flux


Documents

ERO code development