IOS ITPA, 18-21 2011, Kyoto, Japan

by A.R.Polevoi et al1

Report on IOS JA-9:
Optimisation of Operational Space (OS) for Long-pulse Scenarios= Contributors (Potential contributors):
EU: F. Koechl, J. Citrin, J. Garcia, I. Voitsekhovich (+ ISM); JA: N. Hayashi; KO: Y.S. Na,
RF: V. Leonov; US: J. M. Park, M. Murakami, A. Pankin; IO: T. Casper, S-H. Kim= Contact Person:
A. Polevoi (IO)

= Relation to the ITER Physics Operation Workprogram:DT baseline long-pulse scenarios ∆tFT > 1000 s, Pfus > 250 MW, Q > 5= Basic goal:
To find the OS and optimal parameters (Ip, n, etc.) for long pulse operationand TBM program (There is no systematic scan on Ip, n yet)

IOS ITPA, 18-21 2011, Kyoto, Japan

by A.R.Polevoi et al= Scope of the task (general):Assessment of operational space (OS) for long-pulse scenarios by 1.5D modelling
fixed boundary equilibrium at current flat-top is sufficient,
ICCD is not necessary (?) (the least efficient, mainly reduces Q [Murakami et al])qmin> 1 is not required (EC can be redirected from EL to UL to q=1.5, 2 at ST ?)Phase I(mid-term)

Assessment of the OS with validated models by plasma current and density scan,
Ip = 8 - 15 MA, n = nNBI,shine - nG; (nNBI,shine ~ 3 1019m-3)
Choice of optimal parameters comfortably far from the operational boundaries
βN < 4 li3, n < nG, PSOL < 120 MW, PSOL > 1 ( ~ 1.5?)

Phase II (long term)
Sensitivity studies for modelling assumptions (pedestal, Zeff, n(0)/<n>, etc)

Plan for 2011(see Appendix for motivation)A) Density scan n = nNBI,shine - nG for each of the models: for Ip =15 MA with basic set ofCD: 16.5 MW on- + 16.5 MW off-axis NBCD+ 20 MW of the outermost EL ECCD
keeping the same assumptions (pedestal, etc) as for inductive baseline scenario with
Pfus= 500 MWB) Gathering of available modelling data Ip, n (for data list see attached Exel file)If assumptions are different from the reference case, Ip=15 MA then comment
what and why is modified

2

IOS ITPA, 18-21 2011, Kyoto, Japanby A.R.Polevoi et al

3= Scope of the task (2011):
A. For those who plan new modelling for long-pulse:(0) Start from ITER inductive base line scenario Ip=15 MA, Pfus =500 MW, Q = 10, ∆tFT =400 s
with your model (CDBM, MMM, GLF23, BgB, etc) with 16.5 MW innermost + 16.5 MW
outermost NBI + 20 MW outermost ECCD (EL)):(1) Keep the same input and assumptions you used to simulate 500 MW baseline scenario:
Ip=15 MA, Paux = 50 MW (53 MW?), geometry, pedestal, etc;
(2) Scan (reduce) density (lower limit n > n NBI,shine ~ 3 1019m-3)
keeping pedestal parameters, nTe~35 keV*1019m-3 , ∆ped/ρρa ~0.04)
19 -3
keeping boundary conditions, ne,edge = 3 10 m , Tedge ~ 0.2 keVat the level of saturation predicted by SOLPS with PSOL ~ 100 MW(3) For each point of the scan provide the output listed in attached EXEL file (just fill it?)
Expected results:- Pfus and Q will drop but pulse length will increase due to increase of the CD efficiency (~T/n)and increase of current conductivity (1/Res~ T3/2). PFUS = 250 MW and Q =5 are still acceptablefor hybrid long pulse operation.

IOS ITPA, 18-21 2011, Kyoto, Japan

by A.R.Polevoi et al= Scope of the task (2011):
B. For those who already have data for long-pulse:-Please just fill the attached EXEL file (including the following comments below)-

Specify the model used for core transport, (Ti,Te,nHe,ne, impurities…?) and pedestal-

Describe plasma configuration if different from full bore baseline case:
BxR = 5.3x6.2 Tm; a/R=2/6.2 m, ka=1.76 (ka = S/ππa2), triangularity ~ 0.5,

-Describe of the set and configuration of the H&CD (power and location) if different fromproposed in (A):-If assumptions are different from the reference case, Ip=15 MA then comment
what and why is modified

4

IOS ITPA, 18-21 2011, Kyoto, Japan

by A.R.Polevoi et al5= Present status:
Data provided by October 20, 2011
F. Koechl (BgB, GLF23 with JINTRAC, new modelling: Ip = 15 MA density scan)
A. Polevoi (Scaling Based with ASTRA, new modelling: Ip = 15 MA density scan)
N. Hayashi (CDBM with TOPICS, new modelling: Ip = 15 MA density scan)
V. Leonov (Scaling Based with ASTRA, new modelling: Ip = 15 MA density scan)
A. Pankin (MMM71, Weiland with ASTRA, new modelling: Ip = 15 MA density scan)J. M. Park (GLF23 with FASTRAN, new modelling: Ip = 15 MA 33 NBI + 20 IC)
M. Murakami (GLF23, CDBM with FASTRAN, new modelling: Ip = 15 MA,
Sensitivity studies to ST model, heating mix, EC location)
J. Citrin (GLF23 with CRONOS, available data analysis: Ip = 11.5-12.2 MA,
sensitivity studies)

Potential contributors:
J. Garcia (CRONOS), S-H. Kim (CORSICA), Y.S. Na ???

IOS ITPA, 18-21 2011, Kyoto, Japan

by A.R.Polevoi et al

Present status summary for 2011(1) 15 MA, Q=10, Pfus = 500 MW
Done by FK, NH, VL, AP, APn full bore plasma inductive
Done by JMP, MM for slim SS geometry (Pfus > 500 MW, ∆tFT> 400 s)
NB: Potentially interesting area for others for later optimization?
(2) Density scan for one slice: Ip = 15 MA
Done by FK, NH, VL, AP-Long pulse operation ∆tFT ~1000 s becomes possible for 15 MA at low
densities, n/nG ~0.5 for all models with Hy2,98 ~ 1.1 even with day-1 mix:
33 MW NBI + 20 MW EC for BgB, GLF23, SB(AP), SB(VL)-Fusion gain factor Q drops with density reduction. For SB(VL) andCDBM(NH) it drops below Q=5.

-Load to divertor drops with density reduction-Fluence increases for BgB and GLF23 with density reduction

Would be the next step for JMP, MM, APn (plan for 2012??)6

IOS ITPA, 18-21 2011, Kyoto, Japan

by A.R.Polevoi et al(2) Ip=15 MA density scan-I: Same assumptions as for 500 MW, 15 MA, Q =10

Density reduction increases Hy2,98 ~ 1 -> 1.1for BgB, GLF23, and reduces for CDBM (NH)Density reduction to n/nG ~ 0.5 increases flattop length to 800-1000 s (~500 s CDBM (NH))

BgB, GLF23, SB: ∆tFT ~1000 s becomes possible for 15 MA at low densities, n/nG ~0.5

with Hy2,98 ~ 1.1 with the same model assumptions used for Q=107

IOS ITPA, 18-21 2011, Kyoto, Japan

by A.R.Polevoi et al8(2) Ip=15 MA density scan-I: Same assumptions as for 500 MW, 15 MA, Q =10ITER 15 MA full bore operation

For BgB and GLF23 Q drops with density
reduction, but remains high Q> 5,For BgB and GLF23 Fluence per shot
remains higher than for baseline: Pfus∆tFT> 200 GJ. Fluence reduces for SB(VL) andCDBM (NH).

IOS ITPA, 18-21 2011, Kyoto, Japanby A.R.Polevoi et al9(3) Density scan for the range Ip = 10-15 MA (Ip-n OS):(see Basic goal and Phase-I above)
done by VL with SBM by ASTRA V. Leonov 7th IOS TG Meeting 18-21 Oct. 2011, Kyoto, Japan

10Q815MA

5004003002001000300020151010615MA

10502.015MA13 ind

101.0
0.5

1 hour

13ind

131.5

101000425

1320000ind
βN

Pfus (MW)0

P loss / P LH

Will be a natural next step forFK, NH(Plan for 2012??)102∆ t (s)∆t(Ip,n) = 1000 s

ind

1364

Ip and n for 1000 s operations are
the solution of the set of equations:
Q(Ip,n) = 5,

15MA

4

Motivation of plasma current andplasma density choice is presented:

Fluence (10 MJ)/pulse

A.R. Polevoi, et al 37th EPS. (Dublin, Ireland, 2010) P2.187

15MAind

8 19 -310
n e (10 m )120.02.015MA1.5

ind131.0

100.5
0.0468 19 -3 10n e (10 m )12IOS ITPA, 18-21 2011, Kyoto, Japan

by A.R.Polevoi et al10(3) Density scan for the range Ip = 10-15 MA (Ip-n OS):(see Basic goal and Phase-I above)
done by AP (2010)

A.R. Polevoi, et al 37th EPS. (Dublin, Ireland, 2010) P2.187

So, VL already has sufficient
information to draw Ip,n OS
similar to this one =====


Hybrid operational space for Paux = 50 MW

IOS ITPA, 18-21 2011, Kyoto, Japan

by A.R.Polevoi et al=> Plans:(1) General : JA9 to be continued (2012)(2) Different contributors are at different phases. Thus they
follow an individual plan for 2012:a) For those, who plan to join: choose way of contribution (A, B)(Potential contributors)b) For those, who chosen A: start with step 1 doing density scanstarting from 500 MW, Ip=15 MA (JMP, MM, APn)c) For those, who passed step 1: continue with Phase-I doing Ip-n
scan for other currents similar to step 1 (FK, NH)d) For those, who passed Phase – I: continue with sensitivity studies
near the chosen optimum (VL, AP), draw the Ip,n OS

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