Fluidised powder target research

A potential target technology for both a Superbeam and a neutrino factory

CJ Densham, O Caretta, P Loveridge

STFC Rutherford Appleton Laboratory

Is there a ‘missing link’ target technology?

Some potential advantages of a flowing powder:Resistant to pulsed beam induced shock waves

Favourable heat transferQuasi-liquid

Few moving partsMature technology

Areas of concern can be tested off-line

Open jets

SOLIDS LIQUIDS

Monolithic Flowing powder Contained liquidsSegmented

Schematic layouts of flowing powder targets for neutrino facilities

Superbeam target - contained within pipe

Neutrino factory target - open jet configuration used

in test rig on day 1 (for MERIT comparison)

(1) pressurised powder hopper, (2) discharge nozzle, (3) recirculating helium to form coaxial flow around jet, (4) proton beam entry window, (5) open jet interaction region, (6) receiver, (7) pion capture solenoid, (8) beam exit window, (9) powder exit for recirculation, (10) return line for powder to hopper, (11) driver gas line

Summary of Operation

• Powder– Rig contains 100 kg

Tungsten– Particle size < 250 microns

• Total ~8,000 kg powder conveyed– 90 ejection cycles– Equivalent to 15 mins

continuous operation

• Batch mode– Test out individual handling

processes before moving to a continuous flow loop

Summary of Operation

• Powder– Rig contains 100 kg

Tungsten– Particle size < 250 microns

• Total ~8,000 kg powder conveyed– 90 ejection cycles– Equivalent to 15 mins

continuous operation

• Batch mode– Test out individual handling

processes before moving to a continuous flow loop

1

1. Suction / Lift

Summary of Operation

• Powder– Rig contains 100 kg

Tungsten– Particle size < 250 microns

• Total ~8,000 kg powder conveyed– 90 ejection cycles– Equivalent to 15 mins

continuous operation

• Batch mode– Test out individual handling

processes before moving to a continuous flow loop

1

2

1. Suction / Lift2. Load Hopper

Summary of Operation

• Powder– Rig contains 100 kg

Tungsten– Particle size < 250 microns

• Total ~8,000 kg powder conveyed– 90 ejection cycles– Equivalent to 15 mins

continuous operation

• Batch mode– Test out individual handling

processes before moving to a continuous flow loop

1

2

3

1. Suction / Lift2. Load Hopper3. Pressurise Hopper

Summary of Operation

• Powder– Rig contains 100 kg

Tungsten– Particle size < 250 microns

• Total ~8,000 kg powder conveyed– 90 ejection cycles– Equivalent to 15 mins

continuous operation

• Batch mode– Test out individual handling

processes before moving to a continuous flow loop

1

2

3

4

1. Suction / Lift2. Load Hopper3. Pressurise Hopper4. Powder Ejection and Observation

Control Interface• Fully automated control

system– Process control– Data Logging @ 20 Hz– Hard-wired safety interlocks

Control System Interface (MATLAB)

Experiment notes

System indicator window

Warning messages

Emergency stop

Suction settings

Ejection settings

Post Processing

Two-page Report - Microsoft Word

• Automatic report generator– Records experiment settings– Graphs the data– Generates a Microsoft word

document for each cycle

Post-processing user interface - Matlab

Contained stable jet

Contained unstable jet

Particle Image Velocimetry

velocity distribution required to

determine bulk density

Ottone Caretta, Oxford, Nov 09

Variations in the flow rate – typical 2bar ejection

How much material would a proton beam interact with?

Bulk density?

Is the amount of material in the nozzle (or jet) constant?

Ottone Caretta, Oxford, Nov 09

• Optimise gas lift system for CW operation• Carry out long term erosion tests and study

mitigation• Investigate low-flow limit • Study heat transfer between pipe wall and powder• Demonstrate shock waves are not a problem

– Use of CERN test facility for shock wave experiment on a powder sample in helium environment

• Demonstrate magnetic fields/eddy currents are not a problem– Use of high field solenoid?

• Investigate active powder handling issues (cf mercury?)

Flowing powder target: next stages