itpa – cdbm h-mode threshold database iaea tm on h-mode paper october 2007 - naka

Yves MartinYves Martin

Centre de Recherches en Physique des PlasmasAssociation Euratom - Confédération Suisse

Ecole Polytechnique Fédérale de Lausanne (EPFL)CH - 1015 Lausanne, Switzerland

ITPA – CDBMITPA – CDBMH-mode threshold databaseH-mode threshold database

IAEA TM on H-mode paperIAEA TM on H-mode paper

October 2007October 2007 - - NakaNaka

Yves Martin, ITPA TG CDBM LH Transitions, October 2007, Naka 2

Preliminary remarksPreliminary remarks

Constraints• IAEA TM papers to be published in JPCS (J.Phys.:Conf.Ser.)• ~30 papers (half presented papers) submitted • Delay: Oct 12th

Plan• Improved but similar coverage version to JPCS• Extended version to PPCF

Comments• Received comments TT, JDB, R.Sartori, AP, FR, JS, YA


PlanPlan

Abstract / IntroductionThreshold power estimation

• DB status• Data selection• Power law scaling• Predictions for ITER

Effect of CHSIndividual density dependence

• Dependence in individual devices• Prediction for ITER

Density of the minimum threshold power• Search for minimum• Discussion

Access to an H-mode with good confinement properties• PoP in H-mode DB• High H factor close to threshold

Discussion - conclusion


Abstract / IntroductionAbstract / Introduction

Abstract• Too long

Introduction• Too long


Threshold power estimationThreshold power estimation

DB status

Data selection

Power law scaling

Predictions for ITER


DB statusDB status

New data

Changes in data

Distribution of data


Data selectionData selection

SELEC2007= If( :SELDBsum == 1111111111 & :PHASE_RED == "LH" & :AUXHEAT != "NONE" & :AUXHEAT != "EC" & :CONFIGs == "SN" & :PGASA == 2 & :KAPPA > 1.2 & :TOK != "NSTX" & !( :TOK == "JFT2M" & :NEL < 25000000000000000000) & !( :TOK == "JT60U" & :NEL < 15000000000000000000) & !( :TOK == "CMOD" & :PHASE == "D") & !( :TOK == "CMOD" & :PHASE == "DA") & !Is Missing( :NEL) & !Is Missing( :PLTH_MW),1, 0)


Data selection IIData selection II

SELDBsum = Summary of SELDBxxx where x=1,2,4v1,4v2 If(!Is Missing( :SELDB2) & :SELDB2 > 0,

:SELDB2, If(!Is Missing( :SELDB1) & :SELDB1 > 0,

:SELDB1, If(!Is Missing( :SELDB4v2) & :SELDB4v2 > 0,

:SELDB4v2, If(!Is Missing( :SELDB4v1)

& :SELDB4v1 > 0, :SELDB4v1, 0))))

CONFIGs = Simplified configuration "SNT", "SN", "SNB", "SN", "SN(L)", "SN",

"SNL", "SN", "SNU", "SN", "SN(U)", "SN"


Data selection IIIData selection III

PHASE_RED = Reduction of PHASED LH DA LH DH

LH EDA H EDAA H EDALHL H H HA H HCMP H

HELM H HELM? H HGELM HHGELMA H HGELMHA H HL

HL HOHM HL HSELM H HSELMA HHSElMA H HSELML HL HSELMOHM

HL L L LA L LA1 LLA2 L LA3 L LD

LH LDH LH LDHSELM LH LDL LLDSELM LH LH LH LHLHL

LH LHLHLA LH LHSELM LH OHA LOHM L OHMA L OHMD

LH OHMDH LH OHMDSELM LH OHMHLH OHMHSELM LH OHMP L OHMPDLH", :PHASE || " is missing")


Data selection IVData selection IV

Avoid low density region ? SELDB should do it

Ohmic H-mode in CMOD do not have higher threshold


Recommended scalingRecommended scaling

Scaled parameter: PLTH• Definition changed (PFLOSS included)

With a and R:Pthresh = 2.15 n0.782+/-0.037 B0.772+/-0.031 a0.975+/-0.08 R0.999+/-0.101

With S:Pthresh = 0.049 n0.717+/-0.035 B0.803+/-0.032 S0.941+/-0.019

Discuss Kadomtsev constraintDiscuss changes from earlier versions


Prediction for ITERPrediction for ITER

Specify: Predictions done for DD plasmas• Discuss DT predictions ?


Effect of CHSEffect of CHS

Generalize discussion to low aspect ratio toks?

0.1

1 0.7 0.5 0.3 0.2

10 6 4 3 2 PL

[MW]

.1 1 .8 .

6 .4 .

3 .2 10

7 5

4 3

2 PTHRESH [MW]

CHS


Individual density dependenceIndividual density dependence

Include a figure showing the non-alignement of individual devices

Density dependence on individual devices at well populated field values

Prediction for ITER


Dependence in individual devicesDependence in individual devices

Include uncertainties

Remove literature points• Keep as comment on

additional uncertainty?

Compare with OK work in Ryter 1996

JS not convinced by this effect

0.2

0.4

0.6

0.8

1

1.2

1.4

n

CMOCMOD

0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1 1.1 a [m]


Prediction for ITERPrediction for ITER

Prediction with lowest RMS scaling (minor radius, open divertor for JT-60U): 135MW (at high density)

Include uncertainties


Density of the minimum threshold powerDensity of the minimum threshold power

Search for minimum for individual devices at well populated field values

Interpretation of global picture


Search for minimumSearch for minimum

Include examples (figure)


DiscussionDiscussion

Link between different density dependences and different minimum densities

Discuss neutral penetration / collisionality


Access to an H-mode with good confinement propertiesAccess to an H-mode with good confinement properties

PoP in H-mode DB for HSELM and HGELM

H factor vs PoP for HSELM and HGELM

Too weak


PoP in H-mode DBPoP in H-mode DB

Why PoP > 1 in most devices ?Why PoP < 1 in Alcator C-Mod ?

0

1

2

3

4

5

6

ASDEX

Upgrade

0

1

2

3

4

5

6

Alcator

C-mod

0

1

2

3

4

5

6

DIII-D

0

1

2

3

4

5

6

JET


0.5

0.7

0.9

1.1

1.3

1.5

1.7

H

0

1

2

3

4

5

6

7

8

PL/Pthresh

High H factor close to thresholdHigh H factor close to threshold

Correlation PHASE / ELM type:P

HA

SE HGELM

HSELM 31 28 1290 2 1

0 39 164 327 13

1352

543

31 67 1454 329 14 1895

ELMTYPE

Count TYP-I-II TYPE-? TYPE-I TYPE-III TYPE-RF ...

2291ts were included in the dataset (missing ELMTYPE data for ~400)


R.Sartori's commentR.Sartori's comment

Type I ELM H factor ~ 1 (by construction!)Type III ELM H factor = 0.8-0.9 x type I ELM H factor

@Threshold power (or just above): type III ELMs; more power to obtain type I ELMs

PtypeI = Y x Pthresh where 1.3<Y<2.5


Discussion - conclusionDiscussion - conclusion

itpa – cdbm h-mode threshold database iaea tm on h-mode paper october 2007 - naka

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