Required at run time
- Weather file (EPW): EPW_PATH (absolute path you pass to the CLI).
- EnergyPlus executable: EPLUS_EXE (path to …/energyplus or just energyplus if on PATH).
Coupling inputs (only when the plugin is enabled)
out/exchange/coupling_in.json — the only external knobs your OpenFOAM side sets each timestep:
- T_supply_C (float): supply air temperature setpoint (°C).
- m_dot_kg_s (float): supply mass flow rate (kg/s).
- Example: { “T_supply_C”: 16.0, “m_dot_kg_s”: 0.30 }
Control circle
Supply path: supply_in → OA System → mixed_air → DX → cool_out → ElecHeat → heat_out → Fan → fan_out
Demand path: fan_out → ZoneSplitter → term_in → Terminal → zone_in → (Zone) → zone_ret → ZoneMixer → supply_in
Model-internal parameters (set in the script)
Geometry & zone
- Room size: 5 m × 4 m × 3 m (volume used for ACH).
- Surfaces: 4 walls, roof, floor (simple single-layer construction).
- Global rules: vertex order/coordinate system (GlobalGeometryRules).
Schedules (simple constants)
Always On (1.0).
- SAT 13C (13 °C scheduled supply-air temperature).
- MinOAFrac 0.2 (used by the OA controller).
HVAC topology & components
- OutdoorAirSystem with Controller:OutdoorAir (economizer off; min/max OA flow = 0 / Autosize).
- DX cooling coil (single speed) with condenser air OutdoorAir:Node.
- Electric heating coil.
- Fan:SystemModel (autosized flow; basic power/per-flow setting).
- Air terminal: AirTerminal:SingleDuct:Uncontrolled (single zone).
- Zone Splitter → terminal inlet; Zone Mixer ← zone return.
Setpoint Managers
- Scheduled 13 °C on the supply outlet node.
- MixedAir manager to make the coils “see” that SAT before the fan.
Sizing (autosize drivers)
- Sizing:Zone: supply design temps (13 °C cooling, 40 °C heating), humidity ratios (0.008).
- Sizing:System: central SATs, plus required preheat/precool temperatures & humidity ratios.
Site & simulation control
Site:Location (generic numbers in the script; actual weather comes from EPW).
RunPeriod (Jan 1–2), Timestep (6 per hour), Version.
Building (solar distribution etc.).
Diagnostics (optional: display warnings/extras if you included that block).
Curves
Flat performance curves for DX coil capacity/EIR and PLF (all coefficients = 0 except constant = 1).