EURISOL DS PROJECT Task#2: MULTI-MW TARGET DESIGN
Adonai Herrera-Martínez on behalf of Yacine Kadi and Task#2 European Organization for Nuclear Research, CERN CH-1211 Geneva 23, SWITZERLAND
[email protected]
1 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
#
Sub-Task
Participants
Starting date
1
Monte-Carlo computation of the neutronics and radioisotope production in a liquid metal converter
4
1
11
2
Computation Hg fluid dynamics and heat transfer in a liquid metal converter
18
5
11
3
FEM analysis of the liquid metal converter structural behaviour and first attempt of modelling of transients
18
8
4
Study of a possible window free Hg converter
4, 18, 19
1
5
Decision on preliminary design parameters
4, 18, 19
6
Compare various methods (distillation, liquid-solid extraction by sorption,…) to extract spallation products from liquid Hg
4, 18
1
30
7
Design study of the liquid hg test loop
18, 19
1
11
22
Report on the evaluation of the optimal engineering design of the liquid Hg test loop components
8
Engineering design and construction of components (target, pumps, nozzle, diagnostics).
18, 19
12
12
22
Design and cost evaluation of the geometrical arrangement of the loop elements and their services
9
Study of the HV platform and services
4, 18, 19
1
24
22
4, 5
Design of the target enclosure and the front end taking into account that the entire Hg loop needs to reside on the HT level
10
Study of the remote handling equipment
4, 18, 19
1
24
22
4, 5
Design of the remote handling equipment taking into account constraints in space, weight, etc.
2. Innovative 5. Engineering design 3. Engineering design waste of the entire target and construction of a management functional Hg-loop station in the liquid Hg-loop
Package
1. Engineering study of the liquid metal converter
TASK #2 – Multi-MW Target duration in Dates and months Milestones
Expected
input to other task
Expected deliverables
4
8
4, 5
Determination of neutron flux angular and energy distributions, radiation damage, heat deposition and spallation product distributions for different configurations
7
18
Determination of the Hg flow rates, pumping power, heat exchanger size and cavitation limits.
11
22
Report on the thermo-mechanical behaviour of the liquid metal converter structures under normal operating conditions
15
22
4
Report on the evaluation of the feasibility of a windowless configuration
15
24
4
Preliminary Design Report
15
22
5
Status Report on optimum method for continuous extraction of radioisotopes
Subcontracts, and/or outside EU participants
ORNL
ORNL
2 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
TASK #2 – Multi-MW Target Review of the activity over the last 18 months ∑ Modelling of the target reference design (CERN) and nuclear characterisation using FLUKA; ∑ Detailed CFD/FEM analysis of the 4 MW Hg window target (PSI); ∑ Analysis of irradiated Hg samples (PSI); ∑ Investigation of a transverse liquid film model of a windowless Hg-target (IPUL); ∑ 2 information exchange meetings together with Tasks 3,4 & 5 ∑ 7 technical meetings within Task 2 3 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Reference MMW Target Station Hg converter and secondary fission targets
4 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
TH results on Hg/T91 design
5 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Analysis of Hg/T91 design • The beam window temperature in the best case is around 350 ºC, which should be okay. Temperature gradient along the beam window is on the other hand very steep which may induce strong thermal stresses; • The Hg flow pattern is not optimal: detachment of the flow and recirculation at the guide tube. This results in Hg temperatures that are still too high, 260 ºC. that is why the flow rate should be increased and the guide tube optimized • Design improvements are in progress. • Need to take safety precautions in case of pump breakdown or stop 6 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
2-D Axis-symmetric mesh in Ansys
7 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Results for outer annular inflow - Hg -Von Mises stress Allowable Stress [MPa]
250
100 MPA limit /Irradiated RCCMR
200
150
100
50
Temperature [°C] 0 0
1.
2.
100
200
300
400
500
The resulting beam window Von Misses stress is around 300 MPa in the best case, which is considerably higher than the maximum allowable stress of 100 Mpa suggested for irradiated steels. This is due to the greater thru-thickness temperature gradients along the beam window The stress distribution is biaxial: with a tensile stress component facing the liquid Hg (possibility of cracking), and a bending component in the longitudinal wall direction (beam side under compression). A structural and hydraulic optimization is therefore needed in order to reduce the stress levels.
Joint Meeting of SAFERIB and Task 5, LMU München, Germany
600
8
12-13 October 2006
Optimization: use of two rings deflector
• Test only the inner annular
inflow configuration
New mesh used for CFD Joint Meeting of SAFERIB and Task 5, LMU München, Germany
9 12-13 October 2006
CFD/FEM Results
Stresses have been reduced compared to original configuration by changing flow direction in the inner annulus. Current limit is around 190 MPa which needs to be further improved: optimize inlet shape of the guide tube, move the deflector ring and change the angle of the window cone. As a last resort there remains the possibility to increase the beam size to s = 25 mm. 10 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
TASK #2 – Multi-MW Target Proposed transverse liquid film model of the MMW Hg-target (windowless)
11 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Unit of Test Section
12 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
InGaSn loop
13 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Front View / Film width 9mm, lenght 100mm
14 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Side View / Film width 9mm, lenght 100mm
15 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Results
Preliminary analysis shows that to get through the Baseline Parameters (Gaussian beam radius 15 mm and flow-rate 200 kg/s) it is necessary to reduce the percentage of mercury volume in honeycomb outlet jets system down to 50%. Then temperature increase in mercury will be 116 K at a power dissipation 10 MW/m (4.5 MW along the 45 cm Converter length).
16 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
New Configuration •
The honeycomb is modified to avoid the cavities in the falling mercury film.
•
Such construction additionally gives possibility to distribute velocity in the film cross section according the local heat generation in the beam tract.
•
The velocity becomes reduced along the tract by choosing sections with narrower gaps and reduced to sides by choosing narrower gaps in each section. 17
Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
New Configuration
•
Total Mercury flow-rate of ~ 12 l/s. Local velocity below the 3 mm gap will be 4.4 m/s.
•
The temperature increase of mercury amount, which cross the beam along the diameter, is ~ 117.5 K when the heat deposition density on beam center line is 25 kW/cm3.
18 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Mercury Loop Lay Out
Pump Target Heat exchanger
Shielding
~ 4m Expansion tank and gas separator 19
Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Baseline parameters
- Vapour temperature Hg (1atm): 357°C - Heat deposit: 2.8 MW (4MW beam) - Flow rate Hg: 200 kg/s (15 L/s) - Temperature range: 60°C - 150°C - Pressure drop: 5-7 bar 20 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Gas separator (draft: IPUL)
Transfer plenum
Hg slow velocity area 21 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Pump (draft: IPUL) • •
No mechanical pump Permanent magnetic pump; Advantages to EMP: - Smaller - Higher efficiency - No electrical insulation pump/Hg - Simpler construction and production - No heat transfer pump/Hg
Hg in
Hg out
22 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Test pump
Head pressure max: 7.5 bar (at 15L/s) Corresponding pump power: 160 kW Tested in Riga (IPUL, 2003) 23 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Heat Exchanger
All tubes outer diameter 15.9 mm; heat exchange surface 98.9 m3
24 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
Summary
6 Bends 15m tubes Separator Heat Exchanger Pump Target Measurement Total
V [m3] 0.0375 0.2651 0.2991 0.2165 0.015 0.03 0.0353 0.8985
m [kg] dP [bar] 502 0.125 3548 0.2 4003 0.03 2898 0.3 201 0.46 402 2.5 472 0.3 12026
3.915
_=0.03; dt=15cm 25 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
First lay out
Target
26 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
3m
5.80m
27
Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
4.30m
1.50m Joint Meeting of SAFERIB and Task 5, LMU München, Germany
28 12-13 October 2006
Perspectives
• • • • • •
Improvement of separator Evaluation of pumps’ lifetime (radiation effects!) Valves, measurement devices Filling and draining concept Thermo-hydraulic analysis Target station design
29 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
TASK #2 – Multi-MW Target ∑
Engineering Study of the liquid metal converter: 1. Modelling of transients ==> CW or pulse 2. Design of the entrance and exit flow conditions of the target (sizing of the target) 3. Assessment of the possibility of a one directional flow target
∑
Innovative Waste Management: 1. Test candidate materials for a metal gauze absorber for radionuclides in Hg 2. Prepare solutions of selected radionuclides in Hg by neutron activation and chemical reactions. Study their behaviour, e.g solubility, oxidation etc. to figure out the reason for their apparent separation from Hg in the CERN samples 3. Additional funding was requested (60 kEuro) to procure a commercial glove box system with gas purification unit
30 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
TASK #2 – Multi-MW Target ∑
Engineering Design and construction of a functional liquid Hg loop: 1. Adapt InGaSn Experimental loop for windowless liquid Hg film solution 2. Adapt MEGAPIE loop for the cusped shaped reference solution 3. Additional funding (~80-100 kEuro) has been requested for that purpose
∑
Engineering design of the entire target station : 1. Requirements for radiation protection of the multi-MW power target station 2. Propose options for the minimization of dose rates, activation, material handling and interventions, during and after operation 3. Integration studies of the fission target
31 Joint Meeting of SAFERIB and Task 5, LMU München, Germany
12-13 October 2006
