💨 Duct Sizing & Static Regain
Size circular and rectangular air ducts using Equal Friction and Velocity methods, with Colebrook-White friction, aspect ratio checks, and equivalent diameters.
⚡ Fortran 90 Engine
Double Precision (IEEE 754)
✓ ISO / ASME Validated
📊 Solver Telemetry
● ACTIVE
👁️ Consultations
19
⚡ Calculs faits
17
💾 Téléchargements
400
📦 Code Fortran
4.4 KB
📅 Mise en service
Jun 2026
⏱️ Latence
< 1 ms
💨 HVAC Air Duct Flow Profile & Velocity Boundary Layer
Real-time visual simulation of rectangular & circular duct velocity streamlines📝 Configuration & Presets
ASHRAE Duct Formulations:
• Equivalent Diameter: De = 1.30 · (a · b)0.625 / (a + b)0.25
• Friction Rate: ΔP/L = f · (ρ v²) / (2 De)
• Velocity Pressure: Pv = ½ ρ v² [Pa]
• Aspect Ratio: AR = max(a, b) / min(a, b) ≤ 4:1
• Equivalent Diameter: De = 1.30 · (a · b)0.625 / (a + b)0.25
• Friction Rate: ΔP/L = f · (ρ v²) / (2 De)
• Velocity Pressure: Pv = ½ ρ v² [Pa]
• Aspect Ratio: AR = max(a, b) / min(a, b) ≤ 4:1
📊 Sizing Results & Dimensions
Configure inputs and click Compute to view results.
📘 Calculation Methodology & ASHRAE Standards
Equal Friction & Huebscher Equivalence
The Equal Friction method maintains uniform pressure drop per unit length. The Huebscher formula computes rectangular ducts with equivalent flow capacity:
De = 1.30 · (a · b)0.625 / (a + b)0.25
Aspect Ratio & Noise Criteria
Rectangular ducts should maintain aspect ratio $AR \le 4:1$ to minimize sheet metal weight and prevent acoustic rumble generated by high velocity gradients.
Key Engineering Assumptions
- Standard air density $\rho = 1.204\,\text{kg/m}^3$ at $20^\circ\text{C}$ and $101.325\,\text{kPa}$.
- Galvanized steel absolute roughness $\epsilon = 0.09\,\text{mm}$.
- Standard commercial 25 mm dimensional increments applied for fabrication.