1. TRL tables: power conversion and lifetime
M. S. Tillack
ARIES Project Meeting
March 4, 2008

2. High temperature operation and power conversion
Scope
Consequences of high temperature operation
Performance of primary and secondary power conversion systems
Does not consider temperature control within components (thermal hydraulics, MHD heat transfer, etc). This is a gray area in common with “Heat and particle flux handling”.
Key science challenges (theory + experiments)
Mass transfer
Surface chemistry
Materials degradation via chemical interactions
Material properties degradation at high temperature
Key facilities
High-temperature materials properties and thermo-mechanics test rigs
Chemical interaction static and loop facilities
Integrated heat transport (or power conversion) loops

3. Technology readiness levels for power conversion
Generic Description
Fusion-specific Description 1
Basic principles observed and formulated.
System studies define tradeoffs and requirements on temperature, effects of temperature defined: chemistry, mechanical properties, stresses. 2
Technology concepts and/or applications formulated.
Materials, coolants, cooling systems and power conversion options explored, critical properties and compatibilities defined. 3
Analytical and experimental demonstration of critical function and/or proof of concept.
Data in static capsule tests and convection loops, modeling of transport phenomena, high-temperature mechanical properties measured. 4
Component and/or bench-scale validation in a laboratory environment.
Loop operation at prototypical temperatures with prototypical materials for long times. Thermomechanical analysis and tests on in-vessel elements (e.g., first wall). 5
Component and/or breadboard validation in a relevant environment.
Forced convection loop with prototypical materials, temperatures and gradients for long exposures. 6
System/subsystem model or prototype demonstration in relevant environment.
Forced convection loop with prototypical materials, temperatures and gradients for long exposures integrating full power conversion systems. 7
System prototype demonstration in an operational environment.
Prototype power conversion system demonstration with artificial heat source. 8
Actual system completed and qualified through test and demonstration.
Power conversion system demonstration with fusion heat source. 9
Actual system proven through successful mission operations.
Power conversion systems operated to end-of-life in fusion reactor with prototypical conditions and subsystems.

4. Power core lifetime Scope
All power core components
“Normal” and “off-normal” life-limiting mechanisms
This is a gray area in common with the operations subgroup. Aspects of reliability and failure rates are considered.
Key science challenges (theory + experiments)
Neutron damage, neutron-induced burn-up
Particle erosion
Corrosion damage
Disruption and ELM damage (thermomechanical, electromechanical, plasma, runaways)
Effects of thermal cycling
Key facilities
Specimen tests (neutron, plasma, HHF, chemistry)
Component tests in a laboratory environment
Component tests in fusion facilities (nuclear, non-nuclear tokamaks)

5. Technology readiness levels for power core lifetime
Generic Description
Fusion-specific Description 1
Basic principles observed and formulated.
Lifetime requirements determined from system studies, life-limiting mechanisms defined. 2
Technology concepts and/or applications formulated.
Materials systems proposed, operating environment characterized. 3
Analytical and experimental demonstration of critical function and/or proof of concept.
Corrosion tests establish operating limits, radiation damage coupon measurements & modeling, early failures determined in component tests, plasma erosion measurements and modeling. 4
Component and/or bench-scale validation in a laboratory environment.
Reliability measured in component tests, supporting numerical simulations performed. 5
Component and/or breadboard validation in a relevant environment.
Early failures determined in a fusion environment, component reliability tested in a fusion environment 6
System/subsystem model or prototype demonstration in relevant environment.
Integrated power core systems testing in a fusion environment 7
System prototype demonstration in an operational environment.
Component tests in a fusion nuclear environment with meaningful fluence, specimen tests approaching end-of-life fluences 8
Actual system completed and qualified through test and demonstration.
Components operated to end-of-life in fusion environment with prototypical conditions and subsystems 9
Actual system proven through successful mission operations.
Components operated to end-of-life in fusion reactor with prototypical conditions and subsystems.