recent progress in iter diagnostics development in japan

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Transcript recent progress in iter diagnostics development in japan

Recent Progress in
ITER Diagnostics Development in Japan
Y. Kusama for
H. Ogawa, S. Kasai, T. Sugie1), T. Hatae, K. Sato,
Y. Neyatani, Y. Kawamata, K. Kurihara,
K. Ebisawa2)
Japan Atomic Energy Agency (JAEA)
1)ITER-IT, 2)AITEL Corp.
10th Meeting of the ITPA Topical Group
on Diagnostics
Kurchatov Institute, Moscow, Russia, 10 – 14 April, 2006
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Outline
Recent Progress in Designs and R&Ds of ITER
Diagnostics (Partially related to ITA Task ITA 55-10)
•Impurity Flux Monitor (Divertor)
•Thomson Scattering (Edge)
•Neutronics Analysis for the Port Plug Design
•Integrator for Magnetic Measurement
Planed Designs and R&Ds in 2006 (considered to be
carried out under new ITA Task)
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Impurity Influx Monitor (Divertor)
Mechanical Design - H. Ogawa, S. Kasai, T. Sugie (ITER-IT)
Alignment Optics
Front End Optics in
Upper Port
Front End Optics in
Equatorial Por
Front End Optics
in Divertor
Cassette
Primary Mirror
to Plasma
Correction
lens
Secondary
Mirror
Field lens
Micro-lens Array
Cassegrain Telescope
Collection Optics
Front End Optics
on Divertor
Diagnostics
Support Structure
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Design and R&D Plan in 2005 - 2006
JAEA
Impurity Influx Monitor (Divertor)
(1) Design of Header Optics
- Conceptual design of front end optics with the mirror folder for the integration into
the ports.
- Conceptual design of the cooling channel for the optical components.
- Estimation of the temperature rise of the cooled optical components by a simple
model calculation.
- Studies of productivity and integration of optical components.
(2) R&D of the optical components
- Prototype micro retro-reflector array (10 mm x 10 mm) made of nickel is produced
for feasibility study and optical properties (reflectivity, scattering property of
reflective light, etc.) will be studied.
- Prototype micro-lens array (100 channels) made of fused silica is produced for
feasibility study and optical properties ( the imaging property and the
transmissivity, etc. ) will be studied.
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Mechanical Design of Front End Optics of Upper Port
- As a result of the integration in the upper port, optical
components were installed inside the pipe (ID: 300 mm) for
the remote-handling of the port plug.
- Three mirrors can be installed on the mirror mounting
module with 300 mm diameter. It is also used for a neutron
shielding and cooling the mirror.
- The tilt angel of each mirror can be adjusted and be fixed
before the installation on the port.
Holder for
Third Mirror
Port Plug
Pipe
Front End Optics
To Collection Optics
First Mirror
Third Mirror
Holder for
First Mirror
Shutter
Mirror Mounting
Module
to Plasma
Shutter
Second Mirror
Cross-sectional View of Mirror Holder
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Mechanical Design of Shutter
- Rotary disk shutter driven by the wire is designed. It is also used for the sensitivity
calibration.
- Bearings made of non-magnetized stainless steel (housing) and Silicon Nitride
(ball) is a candidate for a fixed and flexible pivot in this area.
- Further R&D such as double-sealed bellow type linear motion feedthrough and/or
wire-winding mechanism is necessary for a realization.
Shutter Plate
to Plasma
to Collection optics
(micro retroreflector array is
mounted)
Third Mirror
First Mirror
Pulleys
Micro RetroReflector Array
(for Calibration)
Driving Wire
Second Mirror
to Collection Optics
Shutter
Holder for
Shutter
to Plasma
Schematic Drawing of Front End Optics and Shutter
Bottom View of Shutter
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Development of the edge Thomson
scattering diagnostic system for ITER
(progress report)
T. Hatae for JA diagnostics group
(Japan Atomic Energy Agency)
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Design and R&D Plan in 2005 - 2006
JAEA
Thomson Scattering (Edge)
•
•
•
Development SLM laser oscillator based on the design carried out in 2004.
Design of high-average-power laser system (Flash-lamp-pumped high power
amplifier) toward final performance (5J, 100Hz)
Optimization of collection optics, and engineering design of port plug
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Nd:YAG laser system for the edge
Thomson system for ITER
•
•
•
A high output-energy (5J) and high
repetition-rate (100 Hz) YAG-laser is
required to the edge Thomson scattering
system in ITER.
To develop the high power laser,
stimulated-Brillouin-scattering-based
phase conjugate mirrors are to be used to
compensate the wavefront distortion
induced in the high-power amplifying laser
rods.
In the laser system, stable singlelongitudinal-mode (SLM) is necessary to
draw out its performance of the phase
conjugate mirror.
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A flash-lamp-pumped high power laser amplifier
is under development
• Amplification test will be carried out soon
using new SLM laser oscillator.
• Cr,Nd:YAG ceramics (not Nd:YAG
synthetic crystal) is used as the laser
medium.
•Pumping energy: 100 J
•Repetition rate: 100 Hz
•Average input power: 10 kW
•Pumping: 6 flash lamps
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Collection optics
• Collection optics designed by US team during ITER-EDA has the vacuum
boundary at the center of the port plug.
• JA team is investigating the possibility to move the vacuum boundary to the
end of the port plug for
– easy maintenance, and
– reducing radiation damage of the lens and fiber optics.
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Optimization of collection optics design is
carrying out
• Optical configuration is almost the same as the US design.
• Vacuum boundary is arranged at the end of the port plug.
• Considering the influence by the radiation, the lens is arranged more
backward.
Secondary mirror (toroidaly concave mirror)
Slenderly cut lens
To fiber coupling optics
Primary mirror
(flat mirror)
Third mirror(cylindrical concave mirror)
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37
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97
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17
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621
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29 31
28
30
8 36
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To fiber coupling optics
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3234
Vacuum window
(~100mm in diameter)
30.79°
Intermediate image
(possible to set a slit for shield)
Secondary mirror
(toroidaly concave mirror)
1000.00 MM
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Neutronics Analysis of Upper Port
Y. Kusama, K. Ebisawa
Objectives
Evaluation of the following engineering quantities;
• Neutron Streaming through a Large Optical Labyrinth, Gaps
between the Port Plug and the Vacuum Vessel Port,
• Nuclear Heating of Diagnostic Components and the Port Plug,
• Neutron and Gamma-ray fluxes and fluence on the Diagnostic
Components,
• Radioactivity of the Port Plug and External Dose Rate,
• Relocation of front balk shield to the rear end.
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Progress in Neutronics Analysis
1. Nuclear Heating for cooling channel design
•
•
•
•
•
Total ~550 kW on BSM, about half of the specification
(maximum input)
Maximum heat load on the side plates: 30 mW/cm3
First Mirror: 16 mW/cm3,
At the end of Labyrinth: below 0.1 mW/cm3
Flange Portion: negligible
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Optical Labyrinth of Edge Thomson Scattering:
Original configuration designed by US HT in the EDA
1st Mirror
Fiber window 90x50
16 mW/cm3
Fluence: 7E+14 n/cm2,
6.6E+12 n/cm2/sec
10 kGy
1.07m
2nd Lens 180x50
0.85m
Larger Aperture
than original
500x120
1.9E+14 n/cm2/sec
31度
1.50m
Vacuum
window
100x100
Fluence:
0.89m
0.43m
2.32m
0.1mW/cm3
8E+13
n/cm2,
1kGy
Fluence: 1.4E+17n/cm2,
1MGy
2nd Mirror
0.7 mW/cm3
Fluence: 5E+17 n/cm2, 6 MGy
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2. Neutron fluence* and Gamma-ray absorbed dose on
the candidate optical materials
•
•
Originally proposed
lens location:
1.4E+17 n/cm2, 1 MGy,
marginal to use silica glass
Originally proposed
fiber location:
7E+14n/cm2, 10 kGy,
some transmission
loss in fiber
KUVI-S, HO<10E-4%
X: 1E+17 n/cm2
J.Nucl.Mater.212215(1994),105
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SI Fiber
Irrad.
JMTR
Task T246
*Plant life time accumulation
is considered
(= 0.3 MWa/m2 on the 1st wall)
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Neutron Streaming and bulk shielding
Nucleat heating in TFC:
Max. 2E-2mW/cm3
Flange
External Dose Rate:
6 mSv/h
Mirrors
Aperture
Cooling Pipes
Lens
BSM Nuclear
heating: 550 kW
BSM support
Cut out of the
Lower Blanket
Relocate front bulk shield (1m) to the
rear
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3. External Dose Rate around the flange for maintenance
scheme
•
•
Vacuum window: 6 mSv/hr 11.5 days after shutdown, satisfy the
requirement <100 mSv/hr
1 m apart from the flange: 4 mSv/hr, allow hands-on access
4. Influence on Magnet by relocation of the shield
•
Maximum Nuclear Heating in the TF Coil:100 times high flux
than before, but still order of 1E-2 mW/cm3, satisfy the
requirement <1 mW/cm3
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Integrator for Magnetic Measurement - Design, fabrication and test of
new integrator - Y. Kawamata, K. Kurihara, I. Yonekawa
Scope of Design Works and Results under ITA 55-10
(1) Investigate a method to avoid the saturation of the integrator circuit
FET for circuit protection is damaged by excessive voltage inputs due
to successive disruptions. The input circuit should be robust to them.
(2) Design and fabricate a new integrator
(3) Test newly fabricated integrator, statically and by using the thunder
surge simulator (that simulates extremely high voltage input at
disruption) to confirm performance
Three types of input circuit (Attenuator type, Zener diode type, Power
Mos-FET) have been fabricated and tested. The Zener diode type has
been found to be acceptable and tested in JT-60U.
(4) Discuss and propose methods to allow the integrator reject commonmode currents due to RIEFM
The effect of RIEMF would be neglected.
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Integration gap occurs after excessive voltage inputs due
to successive disruptions
shot No.E042997
Disruptions
Selected
results
Disruption
Normal
range
85mVs
Disruption
30mVs
gap
0s
Excessive
voltage inputs
gap
200s
0s
1MΩ
Voltage
generator
200s
Input protection circuit
against excessive high voltage
Zener
X10
to VFC
diode
+ OP.amp
-12V
(High-gain range)
2.0kΩ
+15V
+12V
1.6kΩ FET
TP1
-15V
1.6kΩ
1MΩ
Current flows over
the limit of FET
(High - low
gain range)
1MΩ
Same as above
+
X0.01
OP.amp
X1.0
to VFC
+
OP.amp
(Normal range)
to VFC
(Low-gain range)
Signal input equivalent circuits for durability test of “stepped change”
The oxide film of FET-Zener diode is damaged
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Circuit Type 1 : An attenuator with feedback compensator to keep the
attenuation ratio, and high-voltage resistant operational amplifier
(250 V).
OP.amp
x10
< Linearity Test >
0.0008 % FS (10 V range)
< 0.001 % FS (Op. amplifier spec.)
OP.amp
x0.1
Input
signal
to VFC
(High-gain range)
to VFC
(Normal range)
x0.01
OP.amp
Output voltage
(V)
Linearity error(%/FS)
to VFC
10 V range
12.0
(Low-gain range)
8.0
-0.000778 [%/FS]
Signal input circuit using attenuators
4.0
0.0
-4.0
-0.000826 [%/FS]
-8.0
-12.0
-10.0
-5.0
0.0
5.0
10.0
Input voltage (V)
Feedback compensator to keep the attenuation ratio seems to provide stability of
measurements.
< Conclusion >
· Acceptable for the accurate magnetic measurement.
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Test of “Attenuator Type” in JT-60U discharges
The “Attenuator Type” was applied to one of the magnetic probes of
JT-60U and tested in disruptive discharges.
“Gap Phenomenon” has been perfectly resolved so far and integration
error caused by over range had been successfully corrected.
Integration
Results
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Design and R&D Plan in 2005 - 2006
JAEA
Microfission Chamber
• Design of installation, cabling, ---.
• Optimization of installation position, especially position of MCF for
low fusion power operation.
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