PROGRESS IN 2005-2006 IN THE PROJECT OF THE HIGH FIELD SIDE REFLECTOMETRY SYSTEM FOR THE MAIN PLASMA IN ITER

V. A. Vershkov, D. A. Shelukhin, A. O. Urazbaev, V.A. Zhuravlev

NFI FSI RRC “Kurchatov Institute”, 123182, Moscow, Russian Federation

System characteristics requirementsstandard discharge scenario (Scen 2)

• It is possible to work on the high field side with: – Ordinary wave frequencies 15 - 127 GHz

– Extraodinary frequencies 8 – 78 GHz

4 5 6 7 80

50

100

150

200

250

300

54

3

2

1

Freq

uenc

y [G

Hz]

Radius [m]

1 – extraordinary wave (low frequency cut off)

2 – ordinary wave

3 – electro cyclotron frequency

4 – extraordinary wave (high frequency cut off)

5 – double electron cyclotron frequency

PROGRESS IN HFS ITER REFLECTOMETRY UP TO 2006.

In 2005 the following works have been carried out:

1. The final version of the waveguides routes from antenna to the door to gallery were designed in form of CATIA models.

2. The works on construction of the laboratory test facility were continued. In particular the moke up of the two blanket modules were made and the optimized bends were manufacured.

3. The official cooperation between Kurchatov Institute and Institute of Applied Physics in Nijnii Novgorod started since June

2004. The goals - optimization of the bends and vacuum window.

4. Modification of 2D full-wave program for the Xl mode was in progress in 2005. This will increase it capabilities in calculation of propagation of Xl mode in turbulent plasma.

5. HFS reflectometry was recently installed in T-10 and tested on the turbulence measurements.

6. Neutron fluxes were estimated over the guide route and first 3D temperature estimations of the antenna heating were done

7. Semiconductor sweeeping frequency GANNs generators were purchased and tested in T-10.

8. The sweeping power supply was build and tested in T-10.

Schematics of combined horn/mirror antenna

Outline of the waveguide transmission line

The full-scale prototype of blanket section consisting of 2 modules with the gap in toroidal direction for test of passage of microwaves.

Antennas prototypes are settled in the gap (right foto)

Hyperbolic secant R0=50 mm Req=58 mm

Xl mode O mode

Hyperbolic secant R0=75 mm Req=87 mm

Xl mode O mode

Hyperbolic secant R0=100 mm Req=116 mm

Xl mode O mode

90 degree hyperbolic secant. What R is appropriate??R0(mm) A(mm) B(mm) C(mm)

50 116.05 116.05 52.81

75 174.08 174.08 79.22

100 232.11 232.11 105.62

125 290.13 290.13 132.03

00

95.1

r

zchrR

RUSSIAN RESEARCH CENTER “KURCHATOV INSTITUTE”

120 130 140 150 160 170 1800

20

40

60

80

100

120

140

XU

XL

aval

able

fr

equ

enci

es

Fre

qu

ency

[G

Hz]

Major radius [cm]

HFS reflectometry system in THFS reflectometry system in T--1010

• HFS reflectometry system was recently installed in T-10

• Minimal frequency restricted by waveguides is 14 GHz

• The XL frequency range for the typical T-10 discharges varies from 14 to 65 GHz (close to ITER)

RUSSIAN RESEARCH CENTER “KURCHATOV INSTITUTE”

HFS reflectometry system in T-10HFS reflectometry system in T-10

• First spectra from HFS Xl-mode reflectometry OH T-10 discharge• Reflection at about a/2 • Clearly seen poloidal turbulence rotation and MHD modes• No Quasi-Coherent modes• Very low frequency to reach the core plasma.

-400 -200 0 200 4000.0

0.2

0.4

0.6

0

0

1

2C

oh

ere

ncy

Frequency [kHz]

= 6.26 s = 1.65·104 rad/s

Cro

ss-

ph

ase [

rad

]

-

F = 25.5 GHz ~ 0.5

BT = 2.4 T

ne = 2.6·1019 m-3

Am

pl. [

a.u

.]

RUSSIAN RESEARCH CENTER “KURCHATOV INSTITUTE”

HFS reflectometry system in T-10HFS reflectometry system in T-10

600 700 800 9000.0

0.2

0.4

0

2.0

2.5

E/E

Time [ms]

[ra

d]

ne

[1019

m-3] • High quality of the overall

phase tracking

• Extremely low relative level of the fluctuations of the total signal The typical value 0.15 – 0.2 with the saturation limit of 1.5.

• • It opens possibilities to

work without saturation in strongly heated plasmas.

• • Good tracking of the MHD

events (sawtooth pfase jumps)

580 590 600

0

5

10

740 750 760-1

0

1

[ra

d]

Time [ms]

-400 -200 0 200 4000,0

0,1

0,2Shot 42412t = 600 ms = 0.54

Signal Fourier spectra at the LFS & HFS side, normalized at the turbulence RMS amplitude

LFS, n/n

e=0.77 %

HFS, n/n

e=0.47 %

Y( n/n

e) [a

.u.]

Frequency [kHz]

Comparison of reflectometry fluctuation spectra from the top and HFS in OH plasma

Comparison of radial profiles of the reflectometry turbulence fluctuation level from the top and HFS in

OH and 1 MW ECRH

0,2 0,4 0,6 0,80,0

0,5

1,0

1,5

2,0

0,2 0,4 0,6 0,8

OH plasma LHS HFS

n/n

[%]

ECRH plasma

First experiments with the broad (28 – 32 GHz) fast (200s)

frequency scan at HFS in monostatic antenna

variant-1,5

-1,0

-0,5

0,0

0,5

1,0

899,6 899,8 900,0 900,2 900,4 900,6 900,8 901,0 901,2

-101

28

30

32

900,05 900,10 900,150,0

0,5

1,0

1,5

2,0

Time [ms]

Fre

qu

en

cy

[M

Hz]

Am

pli

tud

e [a

rb. u

n.] F

req

uen

cy [

GH

z]

Schematics of the designed primary wacuum window

VW was designed on the base of the ideas of paper of M. Petelin, W. Kasparek In Int. J.Electronics, 1991, Vol 71, # 5, 871 – 8732. The geometry and transmission was worked out during the contract of Kurchatov Institute with Nijnii Novgorod in 2005

Corrugated quartz vacuum window transmission for E parallel to the long waveguide side

1. VW was designed on the base of the ideas of paper Of M. Petelin, W. Kasparek In Int. J.Electronics, 1991,

Vol 71, # 5, 871 – 8732. The geometry and

transmission was worked out during the contract of Kurchatov Institute with Nijnii Novgorod in 2005

Corrugated vacuum window transmission for E perpendicular to the long waveguide side

1. VW was desined on the base of the ideas of paper Of M. Petelin, W. Kasparek In Int. J.Electronics, 1991,

Vol 71, # 5, 871 – 8732. The geometry and

transmission was worked out during the contract of Kurchatov Institute with Nijnii Novgorod in 2005

1. We made wide range of the 90 degree bends search in dimensions. We should choose the finite bend dimension, which is possible to use.What is the BIGGEST bend among 4 is appropriate? (This is also referred to 40 degree bend)

2. The small distance between waveguides make difficult to construct the horns. Is it possible to increase the distance between the waveguides by transferring some magnetics cables inside waveguides? Or to expand waveguides Just in vicinity of equatorial plane (less cabling?)

3. The minimal allowed gap between the blankets should be statedALL THIS QUESTIONS SHOULD BE SETTLED IN 2006