# Presentation: 381516

## FIRE Diagnostics Issues for the PVR

**K. M. Young  ****(PPPL)**
**FIRE Engineering Meeting **
**June 25, 2003**
**PPPL**

## FIRE Diagnostics Issues for PVR

**Engineering Issues**
- Magnetic diagnostics among mass of Cu.
- Integration of diagnostics with port plug, vacuum vessel, divertor hardware and PFCs.
**Physics Issues**
- Measurement Requirements.
- Proposed Diagnostic Set and Implementation Plan:
- Identify viable AT diagnostics (J(r), p(r)),
- Beam-seeded diagnostics.
- Issues and R&D Plan:
- Need for alpha-particle m,easurement,
- RIC and other rad.-induced effects,
- Effects of erosion and deposition on optical components
- NB development.

## Access for Magnetic Diagnostics at Vacuum Vessel, Passive Plates and First Wall

- Magnetic diagnostic will transition in front of inboard passive plate into slots added in divertor baffle

- 4 mm gap

- Copper Tiles ~ 220 mm side
-                        x 38 mm thick

- “Pocket” in tiles for mounting magnetic diagnostics

- • Increased spacing provided
-  for magnetic diagnostics
-  between vacuum vessel
-  passive plates and first
-  wall tiles.
- • For R=2.14 m device.

## Magnetic Probe Concepts and Impact of Copper

- Pre-conceptual design carried out for equilibrium coils, Mirnov coils, Rogowski, flux loops and diamagnetic loop:
- For Equilibrium Coils:
- nA ~ 2.5 x 10-2 m2.
- On assumption of microwave transmission in 4 mm tile gap, effective shielding factor ~ 7 x 10-2.
- With filament model, shielding factor ~ 3 x 10-3.
- Impact of copper plate behind coils on radial field measurement large but not calculated.
- No design yet for remote handling, electrical connections, or integration with tiles, etc.
- Looking at possibility of electronically compensating signals for significant fast changes in RIC.

- MI cable is 1 mm o.d. MgO-insulated, SS conductor and sheath (must be evaluated for RIC and RIEMF).

- Equilibrium Coil

## Port-Plug Pre-concepts for Calculation of the Impact of Streaming in Penetrations

- Radiation streaming is a critical concern for FIRE.  Impacts:
- diagnostic parts in torus hall in real time,
- activation levels in the hall.
- Pre-conceptual designs done of penetrations of two ports for first streaming calculations.
- First calculations of average fluxes at the back-plate (150 MW pulse, 1.1 m plug):
- No penetrations	1.0x107 n/cm2/s,
- With 100 mm dia.	1.3x1011 n/cm2/s, straight penetration,
- With 100 mm dia.	2.0x109 n/cm2/s,
-      4-bend penetration.
- Activation levels acceptable with port neck filled by shielding.
- Engineering design of port-sharing by diagnostics planned to start in April, 2003.

- 1.1 m shield

## Slide 6

## Diagnostics proposed for FIRE (2)

**Physics Parameter        Control      Diagnostic Set****	****           Issues and Comments**

## FIRE Diagnostics: 

- CXRS (2),
- Beam Emission Spectroscopy,
- Lost- System
- RWM Coils
- B: Diagnostic Neutral Beam
- C: ICRF/LH Launcher
- RWM Coils
- D: Pump Duct,
- Pellet Injector,
- UV Survey Spectrometer,
- X-ray Crystal Spectrometer,
- X-ray PHA,
- Ion Gauges,
- RGA
- (Remote Handling)
- E: Neutron Camera,
- Neutron Fluctuation Detectors
- Bolometer Array
- Hard X-ray Detector
- TVTS Dump
- RWM Coils
- F: TVTS Detection
- Plasma TV,
- IR TV,
- MM-wave Receiver
- Metrology System
- G: ICRF/LH Launcher
- RWM Coils
- H: ECE Systems,
- Reflectometers,
- MM-wave Collective Scattering Source and Receiver,
- Magnetics Wiring
- Fast Edge Probe
- (Remote Handling)

- I: TVTS Detection,
- Plasma TV,
- IRTV
- Soft X-ray Array
- Metrology System
- RWM Coils
- J: TVTS Laser,
- Pellet Charge Exchange,
- Li-Pellet Injector,
- Hard X-ray Detector
- Synchrotron Rad. Detector
- K: ICRF Launcher
- RWM Coils
- L: ICRF Launcher
- (Remote Handling)
- M: ICRF Launcher
- RWM Coils
- N: ICRF Launcher
- O: FIR Interferometer/ Polarimeter,
- Plasma TV,
- IR TV,
- Bolometer Array
- Metrology System
- RWM Coils
- P: MSE (1),
- CXRS (1),
- Visible Survey Spectrometer,
- Visible Filterscopes,
- Visible Bremsstrahlung,
- -CHERS
- (Remote Handling)

- Blue: Diagnostics Components
- Orange: Diagnostics-provided Services
- Red: Auxiliary Systems
- Green: Services

- FIRE Diagnostics:
- Midplane Port Assignments

## DRAFT FIRE R&D Proposals

- Irradiation Tests of Materials
- Evaluation of radiation-induced conductivity (RIC) in selected ceramics and MI cable to define design materials
- Test coil ceramics to FIRE first-wall flux levels and temperatures,
- Test MI cable in realistic configurations.
- Determine cause of radiation-induced emf (RIEMF) with MI cables to prevent signal pollution by significant DC offsets (continuing work which involved GA and ORNL) .
- Evaluation of electrical connection techniques for remote handling and insulation properties.
- Test selected optical fibers for performance in realistic radiation environment at relatively low light-signal levels (continuing work done for ITER) .
- Development of New or Improved Diagnostic Techniques
- Develop an Intense Diagnostic Neutral Beam: specification ~125 keV/amu, 1x106 A/m2 in a cross-section of 0.2m x 0.2m at the plasma edge for 1 sec at 30 Hz repetition rate (LANL started development for ITER R&D) .
- Complete demonstration of fast-wave reflectometry for measuring hydrogen isotope ratios in the core (continuing work started by GA for ITER) .
- Extend the operational range of Faraday-cup based and scintillator-based escaping- diagnostics to FIRE parameters (U.Colorado/PPPL program through JET) .
- Seek new technique for measuring the confined fast-alphas.

## DRAFT FIRE R&D Proposals (continued)

- Development of New Components/Techniques
- Continue development of small rad-hard high-temperature magnetic probes based on integrated-circuit manufacturing techniques.
- Develop a prototype “plug” to incorporate required tolerances, alignments, assurance of ground isolation, actuation of shutters, etc.
- Evaluate metallic mirror performance and effects on reflectivity of neutral particle bombardment and nearby erosion (ongoing ITER R&D activity).
- Develop in-vacuo electrical connection techniques for reliability, remote handling and insulation properties

## Concluding Comments in Talk to ITPA Diagnostics (2/03)

- Alpha-particle transport is a key issue for next-step reactors:
- The alpha-particles can cause wall damage through excessive localized loss,
- They may drive transport-affecting instabilities,
- They may damp the burn.
- Alpha-particle and high-frequency wave diagnostics must be available at much higher quality and reliability than for TFTR or JET/DTE1.
- Unfortunately, many techniques are required.
- ITER (and FIRE) provide very challenging observation geometries:
- Sightline availability,
- Narrow gaps between first-wall elements,
- Usable materials in the environment.