# Session Context Notes

- Reactor model: two-loop but tuned to RBMK-like pressures (nominal ~7 MPa for both loops). Loop pressure clamps to saturation baseline when pumps are off; pumps ramp flow/pressure over spool time when stopping or starting.
- Turbines: produce zero output unless steam quality is present and effective steam flow is >10 kg/s. Steam pressure shown on dashboard only when quality ≥0.05 and flow ≥100 kg/s; otherwise 0 MPa. Steam supply displayed in Turbine panel.
- Generators: two diesel units, rated 50 MW, spool time 10s. Auto mode default `False`; manual toggles b/v. Auto stops when no load. Relief valves toggles l (primary) / ; (secondary) and displayed per loop.
- Pumps: per-unit controls g/h (primary), j/k (secondary). Flow/pressure ramp down over spool when pumps stop. Pump status thresholds use >0.1 kg/s to show STOPPING.
- Maintenance hotkeys: p (core, requires shutdown), m/n (primary 1/2), ,/. (secondary 1/2), B/V (generator 1/2), y/u/i (turbine 1/2/3).
- Dashboard: two-column layout, trends panel for fuel temp and core power (delta and rate). Power Stats show aux demand/supply, generator and turbine output. Steam supply pressure shown in turbine panel. Core/temp/power lines include nominal/max.
- Thermal updates: primary/secondary inlet temps now back-computed; when secondary flow is near zero, loops cool toward ambient over time.
- Meltdown threshold: 2873 K. Auto rod control clears shutdown when set to auto and adjusts rods. Control rod worth/tuning currently unchanged.
- Tests: `pytest` passing after all changes. Key regression additions include generator manual mode, turbine no-steam output, auto rod control, and passive cool-down.
- Coolant demand fixed: demand increases when primary outlet is above target (sign was flipped before), so hot loops ramp flow instead of backing off.
- Pump spin-down: pressure/flow ramp down over pump spool time with STOPPING->OFF threshold at 0.1 kg/s; prevents instant drop when last pump stops.
- Steam pressure display shows 0 unless steam quality ≥0.05 and flow ≥100 kg/s to avoid showing pump head as steam pressure.
- Passive cool-down: when secondary flow ~0, loops cool toward ambient; primary inlet/outlet back-propagated from transferred heat and ambient.
- Relief valves: l (primary) and ; (secondary) clamp loop pressure to saturation when open; status displayed per loop.
- Generator behavior: starting/running only produce power when load is present; auto off by default; manual toggles b/v; auto stops with no load; base aux drops to 0 when idle/cold.
- Pressure tying: loop pressure floors to saturation(temp) when pumps off; pump targets aim for ~7 MPa nominal RBMK-like setpoints.
- Turbines: require meaningful steam flow/quality; otherwise zero output. Steam supply pressure in turbine panel reads 0 when no steam.
- Rod control now supports three banks with weighted worth; xenon/iodine tracked with decay and burn-out; new UA·ΔT_lm steam-generator model and pump head/flow curves.
- Dashboard shows heat-exchanger ΔT/efficiency and protections; pumps and HX changes documented in FEATURES.md / TODO.md.