Component-Life Tracking
A twin keeps a running ledger of the accumulated damage in each critical component, based on its real operating history.
A damage ledger per component
Many components fail not from a single event but from accumulated exposure: thermal cycles, mechanical loads, radiation dose, and chemical attack that add up over a lifetime. Component-life tracking is the twin's running ledger of this accumulation for each critical part, computed from the part's actual, estimated operating history rather than from nominal assumptions.
Damage models
- Fatigue: cyclic stress accumulates damage toward a limit, often summed by a linear cumulative rule
- Creep: sustained load at temperature causes slow permanent deformation over time
- Radiation damage: neutron dose changes material properties, tracked as accumulated exposure
- Wear and erosion: surface loss from particle bombardment or flow, integrated over exposure
Why the twin is needed
The loads that drive these mechanisms are usually not measured directly at the point that matters, deep inside a structure or on a surface no gauge can reach. The twin reconstructs the local stress, temperature, and flux from external measurements through its physics model, then integrates the appropriate damage rule. Without state estimation, life tracking would rest on crude worst-case assumptions.
Uncertainty in the ledger
Both the reconstructed loads and the damage models carry uncertainty, so the ledger is a range, not a single figure. Reporting that range honestly is what lets operators decide with known confidence how much margin remains. A life estimate without an uncertainty band invites either premature replacement or unexpected failure.
In the Kronos twins
The neutron environment makes life tracking central to a fusion plant. In the Hyperion breeder, deuterium-tritium fusion produces 14 million-electron-volt neutrons that dose the blanket and structures; the twin will integrate that dose per component. The burner, a deuterium-helium-3 machine, has a much lower neutron fraction of 5.44 percent, changing the balance of damage mechanisms its twin tracks toward thermal and magnetic cycling. See remaining useful life and structural and fatigue twin.