🧱 Building Thermal Inertia & τ
Simulate building dynamic thermal time constant (tau), 24-hour diurnal solar damping factor, and phase lag (déphasage) using a 3R2C capacitive envelope model.
⚡ Fortran 90 Engine
Double Precision (IEEE 754)
✓ ISO / ASME Validated
📊 Solver Telemetry
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👁️ Consultations
37
⚡ Calculs faits
31
💾 Téléchargements
387
📦 Code Fortran
4.4 KB
📅 Mise en service
Jun 2026
⏱️ Latence
< 1 ms
🌊 24-Hour Diurnal Solar Heat Wave Damping & Phase Lag (Déphasage)
Real-time visual simulation of outdoor temperature oscillation vs damped indoor response📝 Configuration & Presets
🏛️ Concrete Office (300 kJ/m²K)
🏡 Brick Villa (165 kJ/m²K)
🌲 Timber House (80 kJ/m²K)
🏫 Passivhaus High-Inertia
Dynamic 3R2C Formulations:
• Total Loss: Htot = U · Aenv + 0.33 · ACH · V [W/K]
• Time Constant: τ = (Cth · 1000) / (3600 · Htot) [hours]
• Damping Factor: μ = 1 / √[ 1 + (ω τ)² ]
• Phase Lag: Δtlag = arctan(ω τ) / ω [hours]
• Total Loss: Htot = U · Aenv + 0.33 · ACH · V [W/K]
• Time Constant: τ = (Cth · 1000) / (3600 · Htot) [hours]
• Damping Factor: μ = 1 / √[ 1 + (ω τ)² ]
• Phase Lag: Δtlag = arctan(ω τ) / ω [hours]
📊 Dynamic Response Results
Configure inputs and click Compute to view results.
📘 Calculation Methodology & ISO 13790 Standards
Thermal Inertia & Time Constant
The time constant $\tau = R_{th} C_{th}$ determines how slowly a building loses heat or responds to external climate oscillations:
τ = Cth / Htot [hours]
Damping & Phase Lag (Déphasage)
High thermal mass delays solar heat arrival indoors by up to 8–12 hours, allowing nighttime natural ventilation flushing during off-peak hours.
Key Engineering Assumptions
- Lumped single-zone 3R2C capacitive thermal network.
- Diurnal solar cycle approximated by 24-hour sinusoidal wave.
- Ventilation specific heat transfer $0.33\,\text{Wh/(m}^3\cdot\text{K)}$.