Deuterium Supply Interface

Deuterium is the common fuel for both machines; its supply interface is a metering-and-purity loop feeding the fueling actuators.

Common fuel, two consumers

Deuterium fuels both the breeder (as the D in D–T) and the burner (as the D in D–³He). Unlike tritium and helium-3, deuterium is abundant, so this interface is about metering and purity rather than scarcity. It supplies the pellet, gas-puff, and beam interfaces with fuel of known isotopic and chemical purity.

Interface functions

• Metering: mass-flow sense and setpoints per consumer.
• Purity: isotopic assay (D vs H) and impurity monitoring before delivery.
• Buffering: plenum pressure regulation for the gas-puff valves and ice-piston feed.

# purity gate before fueling delivery (L3/L4)
if d_fraction >= d_min and impurity_ppm <= imp_max:
    plenum.regulate(P_ref)
    allow_fueling(consumer)
else:
    divert_to_cleanup(); block_fueling(consumer)

Owner and cadence

Owner: L4 for supply-side inventory and purity, L3 for per-consumer metering setpoints. Cadence is seconds to minutes; there is no microsecond path here because the fast fueling timing lives in the pellet and gas-puff interfaces downstream. Isotopic purity matters because hydrogen contamination dilutes the fuel and shifts diagnostics that assume a known species mix.

Calibration ties the assay to a reference standard and tracks drift on the mass-flow meters. This is a design-and-simulation specification; delivery is exercised against the twin's fuel-cycle model before hardware commissioning.