💨 Compressible Fanno Flow with Friction

Model adiabatic compressible duct flow with friction: exit Mach (M2), choking length (Lmax), static and total pressure losses, and temperature variations.

⚡ Fortran 90 Engine Double Precision (IEEE 754) ✓ ISO / ASME Validated
📊 Solver Telemetry ● ACTIVE
👁️ Consultations 35
⚡ Calculs faits 30
💾 Téléchargements 192 📦 Code Fortran 4.4 KB
📅 Mise en service Jun 2026
⏱️ Latence < 1 ms
⚡ Outils & Rapports :
💾 Télécharger Fortran 90

💨 Adiabatic Duct Flow Acceleration & Sonic Choking Limit (M = 1.0)

Real-time visual simulation of Mach evolution, wall shear friction & static pressure gradient

📝 Configuration & Presets

💨 Compressed Air (M = 0.25) 🚨 Safety Relief (M = 0.55) ⚡ Supersonic Tunnel (M = 2.0) 🔥 Gas Pipeline (50 bar)
📐 Duct Geometry & Friction
Commercial pipe: 0.004–0.008
🚀 Inlet Flow & Stagnation State
Fanno Line Formulations:
• Choking Parameter: (4fL*/D) = (1−M²)/(γM²) + [(γ+1)/(2γ)] ln[(γ+1)M² / (2 + (γ−1)M²)]
• Max Choking Length: Lmax = (4fL*/D)₁ · D / (4f) [m]
• Stagnation Pressure Drop: P₀₂ / P₀₁ = (P₀/P₀*)₂ / (P₀/P₀*)₁
• Wall Friction drives subsonic flows toward M=1 and decelerates supersonic flows.

📊 Fanno Flow Results

Configure inputs and click Compute to view results.

📘 Calculation Methodology & Fanno Flow Standards

Fanno Line Thermodynamics

Adiabatic friction in a constant-area duct drives the flow toward maximum entropy, which always occurs at the sonic state ($M=1$):

4fL*/D = (1−M²)/(γM²) + [(γ+1)/(2γ)] ln[(γ+1)M² / (2 + (γ−1)M²)]

Sonic Choking Phenomenon

If actual duct length $L \ge L_{max}$, the flow chokes at the exit ($M_2 = 1.0$), forcing an inlet pressure buildup and mass flow rate reduction.

Key Engineering Assumptions

  • 1D steady adiabatic flow of ideal gas in constant cross-section duct.
  • Uniform average Fanning friction factor $f$.
  • Calorically perfect gas ($\gamma = 1.40$).