disruption dynamics in nstx long-pulse...
TRANSCRIPT
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
1
Dis
rupt
ion
dyna
mic
s in
NST
X
long
-pul
se d
isch
arge
sPr
esen
ted
by J.
E. M
enar
d, P
PPL
for t
he N
STX
Res
earc
h Te
am
Wor
ksho
p on
Act
ive
Con
trol o
f MH
D S
tabi
lity:
Exte
nsio
n of
Per
form
ance
Mon
day,
Nov
embe
r 18,
200
2D
epar
tmen
t of A
pplie
d Ph
ysic
s and
App
lied
Mat
hR
oom
200
, See
ley
W.M
udd
Bui
ldin
gC
olum
bia
Uni
vers
ity, N
Y
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
2
NST
X n
ow o
pera
ting
at h
igh
β P ,
β N, &
f BS
εβP
2002
dat
a20
01 d
ata
–N
STX
βt=
40%
targ
et
–ST
Rea
ctor
(κ=3
.4)
•M
any
disc
harg
es in
the
high
βP
para
met
er ra
nge
•Si
gnifi
cant
impr
ovem
ent
rela
tive
to20
01 p
lasm
as–
Red
uced
err
or fi
eld
–H
-mod
e ⇒
broa
der p
(ψ)
*
Ach
ieve
d lo
ng p
ulse
s with
β P>
1.2
&β N
> 5.
5q*
= 2.
5 to
3.5
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
3
Red
uced
err
or-f
ield
→re
duce
dm
ode
lock
ing
•V
ertic
al fi
eld
coils
foun
d to
ge
nera
te la
rge
n=1
δBr
•C
oils
subs
eque
ntly
re-
shap
ed•
Vac
uum
isla
nd w
idth
s now
redu
ced
to <
1cm
(fro
m 5
cm)
(NST
X op
erat
es w
ith m
> 0
reso
nant
)
q(0)
=2
800k
AO
hmic
BT
= 4.
5kG
EFIT
w/o
MSE
q(0)
=1
wva
ca
4 G
auss
lock
ed-m
ode
2x10
19m
-3
2002
PF5
coi
l20
01 P
F5 c
oil
200220
01
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
4
Hig
h β P
disc
harg
es o
pera
te a
bove
theo
retic
al n
o-w
all l
imit
•R
ecen
t the
ory
wor
k sh
ows:
idea
lno-
wall
limit
is ⟨β
N⟩≈
3in
depe
nden
t of R
0/a fo
r q*
> 1.
7
•H
igh
β Psh
ots e
xcee
d th
is
limit
for
I P /
aBt0
= 2
to 3
.5
•O
btai
ned
in L
SN⟨β⟩≡
2µ0⟨
p⟩/ ⟨
B2 ⟩
320
02 d
ata
2001
dat
a
Cop
per
stab
ilizi
ngpl
ates
Wal
l mod
elus
ed in
DC
ON
stab
ility
ana
lysi
s
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
5
MH
D e
vent
s in
long
est p
ulse
dis
char
ge:
early
n=1
, tra
nsie
nt a
t hig
h B T
long
-live
d n=
2 m
ode
in fl
at-to
pfa
st n
=1 in
tern
al m
ode
disr
upts
βre
sidu
al n
=1,2
rota
ting
mod
es –
NTM
s?
β T=
16%
β N=
6
β P=
1.3
5MW
τ CR
Prio
r to
inte
rnal
col
laps
es,
SXR
show
s onl
y ed
ge 2
/1 o
r 3/1
1090
70
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
6
Rot
atio
n de
cay
corr
elat
ed w
ith ro
tatin
g M
HD
mod
es
•n=
1 bu
rsts
hav
e τ g
row
th=
200-
500µ
s–
Con
sist
ent w
ith (h
ybrid
) ide
al τ
grow
th?
–Pe
ak a
mpl
itude
up
to 1
0 G
auss
at w
all
•C
ontin
uous
mod
es c
lam
p β P
?
•Ea
ch n
=1 b
urst
redu
ces r
otat
ion
–A
lso
trigg
erin
g co
ntin
uous
mod
es?
•R
WM
evi
dent
onl
y at
low
f φ(0
)–
Cau
ses f
inal
col
laps
e of
pla
sma
–D
oes c
ontin
uous
mod
e or
smal
l RW
M
indu
ce la
te ro
tatio
n de
cay?
β P |Βθ|
at w
all
f φ(0
)
n=1
δBR
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
7
•P N
BI=
6MW
,βN
≈6.
3,β P
≈1.
4–
q(0)
≈1.
5, l i
= 0.
65-0
.7
•p(
0)/⟨p
⟩and
βΝ
evol
ve sl
owly
•R
otat
ion
deca
y no
t obs
erve
d pr
eced
ing
final
dis
rupt
ion
phas
e:
Hig
hest
βP
disr
uptin
g ne
ar w
ith-w
all l
imit?
1090
70 EFIT
TRAN
SP
Tota
l
EFIT
Ther
mal
Lock
ed m
ode
sign
al w
eak
prio
r to
final
dis
rupt
ion
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
8
No
MSE
⇒ch
eck
J pro
file
agai
nst N
C th
eory
J NIC
D+
J OH
inco
nsis
tent
with
reve
rsed
-she
ar q
(ψ)
Bet
ter a
gree
men
t with
mon
oton
ic q
(ψ) i
n co
re
t AVG=320-450ms
t AVG=350-700ms
TRAN
SP J
NI+
EFIT
JO
H
EFIT
J
Part
ial-k
inet
ic E
FIT
q
TRAN
SP J
NI+
EFIT
JO
H
TRAN
SP J
from
EFI
T q
•To
tal i
nteg
rate
d cu
rren
t mat
ches
I Pin
bot
h ca
ses
Mag
netic
s-on
ly E
FIT
q
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
9
Stab
ility
ana
lysi
s fin
dsβ
> β n
o-w
allfo
r man
y τ E
,τw
all
•n=
1 no
-wal
l lim
it β N
= 3.
5 to
4.5
cle
arly
exc
eede
d•
With
-wal
l lim
it se
nsiti
ve to
p &
q p
rofil
e sh
apes
:–
Lim
it lo
wer
ed b
y m
onot
onic
q(ψ
) with
q=2
in p
lasm
a–
Lim
it lo
wer
ed w
ith in
crea
sed
p(ψ
) pro
file
peak
ing
Rev
erse
d-sh
ear q
(ψ)w
ith q
(min
) > 2
Nea
rly m
onot
onic
q(ψ
)with
q(0
) < 2
Use
TR
ANSP
p(ψ
) whi
ch h
aspr
essu
re p
eaki
ng p
(0) /
⟨p⟩
= 2.
510
9070
1087
30
Vary
pre
ssur
e pe
akin
g p(
0) / ⟨p⟩
=2.
0 (P
K-E
FIT)
to 2
.7 (T
RAN
SP)
Expe
rimen
t
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
10
Hig
h β
obta
ined
with
hig
h κ
and
δ
•β N
incr
ease
s with
in
crea
sing
elo
ngat
ion
–β N
degr
aded
for κ
> 1.
8 in
pre
viou
s run
yea
r
2002
dat
a20
01 d
ata
β Nw
eak
func
tion
of
δfo
r δ
> 0.
4
Hig
h δ
→hi
gher
I p/a
Bt0
& β
T
β N
β N β T (%)
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
11
Nea
r-te
rm N
STX
con
trol u
pgra
des:
•N
BI f
eedb
ack
for β
cont
rol (
$ lim
ited
at p
rese
nt)
•C
olla
bora
tion
with
G.A
. to
asse
ss a
nd p
ossi
bly
impr
ove
NST
X v
ertic
al p
ositi
on c
ontro
l–
Hig
her κ
⇒lo
wer
l i, h
ighe
r βN
? (N
SST
κ=2.
5, δ
=0.6
)•
Col
labo
ratio
n w
ith C
.U. d
esig
ning
RW
M
feed
back
syst
em w
ith D
CO
N+V
ALE
N
•In
tern
al R
WM
/EF
sens
ors a
lread
y in
stal
led
–Fi
nish
ing
wiri
ng a
nd a
wai
ting
inte
grat
ors a
nd D
AQ
–W
ill b
ench
mar
k m
odel
s and
use
for f
eedb
ack
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
12
•Fu
llto
roid
alco
vera
ge–
24 B
⊥an
d 24
BP
•Ea
ch 1
2 ab
ove,
12
belo
w
•B
⊥m
easu
red
by si
ngle
tu
rn lo
op
–Em
bedd
ed in
tile
s–
Cen
tere
d in
pla
te•
BP
mea
sure
d at
end
s of
prim
ary
plat
es
–G
lass
insu
late
d C
u w
ire
wou
nd o
n m
acor
form
s–
SS30
4 sh
ield
s
Each
prim
ary
plat
e w
ill m
easu
re B
⊥an
d B
P
Ther
moc
oupl
e co
nnec
tors
al
low
eas
y in
stal
latio
n an
d up
grad
e po
tent
ial (
PnP)
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
13
Sens
ors w
ill m
easu
re R
WM
/EF
helic
ity
•B
P an
d B ⊥
mou
nted
sym
met
rical
ly
abov
e an
d be
low
mid
-pla
ne:
–C
hose
n to
avo
id p
orts
, etc….
–M
ount
ed 1
/2”
behi
nd li
mite
r bou
ndar
y–
BP
sens
ors m
ust a
void
HH
FW a
nten
na
Use
up/
dow
n av
erag
e fo
r n=
1 fe
edba
ck
2002
Mod
e C
ontro
l Mee
ting
-J.E
. Men
ard
14
Sum
mar
y•
NST
X h
as c
ombi
ned
β P>
1.2
with
β N>
5.5
–1s
dis
char
ge w
ith 7
00m
s, 80
0kA
flat
-top
•R
outin
ely
oper
atin
g ab
ove
n=1
no-w
all l
imit
–St
atic
err
or fi
eld
redu
ctio
n an
d H
-mod
e op
erat
ion
key
•Lo
ng-p
ulse
shot
s int
erru
pted
by
“bur
stin
g” n
=1 m
odes
–Po
ssib
ly h
ittin
g n=
1 w
ith-w
all l
imit?
–C
ould
be
doub
le-te
arin
g if
q pr
ofile
is re
vers
ed…
–O
r, ot
her f
ast i
on-d
riven
MH
D?
–U
ncer
tain
ty in
q a
nd p
pro
files
lim
its in
terp
reta
tion
of
disr
uptio
ns a
bove
no-
wal
l lim
it.•
NST
XR
WM
sand
err
or fi
elds
will
be
diag
nose
d w
ith
exte
nsiv
e ne
w se
t of i
nter
nal B
⊥an
d B
Pse
nsor
s•
Hig
her κ
and
activ
e R
WM
/EF
cont
rol s
houl
d in
crea
se β