>[!warning] >This content has not been peer reviewed. # Fluid Dynamics — Code ## Purpose `rst_fluid_dynamics.py` fits the RST fidelity model to fluid viscosity(T) and the laminar-turbulent friction factor transition. **Modes:** - `--viscosity` — Fit viscosity(T) for water, glycerol, ethanol (liquids) and air (gas). Compare to Arrhenius/Sutherland benchmarks. - `--reynolds` — Fit friction factor f(Re) as μ-weighted interpolation between laminar and turbulent regimes. Compare to Churchill (1977). Running with no flags executes both modes. ## Dependencies - `numpy`, `scipy`, `matplotlib` - `rst_engine.core.mu_rst` (workspace root) ## Run From workspace root: ```bash python "expanded theory applied/further applications/Fluid Dynamics/rst_fluid_dynamics.py" python "expanded theory applied/further applications/Fluid Dynamics/rst_fluid_dynamics.py" --viscosity python "expanded theory applied/further applications/Fluid Dynamics/rst_fluid_dynamics.py" --reynolds ``` ## Built-in data **Viscosity:** Water (15 points, 273–373 K), glycerol (10 points, 293–373 K), ethanol (10 points, 273–353 K), air (11 points, 200–1000 K). Sources: CRC Handbook, Perry's, NIST. **Reynolds:** Churchill (1977) smooth-pipe friction factor at 19 Re values spanning 100–10⁶. ## Output **Viscosity mode:** - Console: per-fluid RST fit params, R², comparison to benchmark - `fluid_dynamics_viscosity.png` — 4-panel viscosity vs T **Reynolds mode:** - Console: Re_c, n_turb, R², per-Re comparison table - `fluid_dynamics_reynolds.png` — Moody diagram + residual plot **CSV:** `fluid_dynamics_results.csv` ## Links - **Theory:** [[Fluid Dynamics (RST)]] - **Results:** [[Fluid Dynamics Results]]