ThermoFluidCalc Engineering Report

PCM Latent Heat Thermal Storage Analysis (LHTES Sizer) — 2026-08-23 20:56:22
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🔋 PCM Latent Heat Thermal Storage

Size Phase Change Material (PCM) latent heat thermal batteries: total stored energy (kWh), average charging thermal power (kW), melt time, NTU effectiveness, and state of charge (SOC).

⚡ Fortran 90 Engine Double Precision (IEEE 754) ✓ ISO / ASME Validated
📊 Solver Telemetry ● ACTIVE
👁️ Consultations 35
⚡ Calculs faits 28
💾 Téléchargements 202 📦 Code Fortran 11.4 KB
📅 Mise en service Jun 2026
⏱️ Latence < 1 ms
⚡ Outils & Rapports :
💾 Télécharger Fortran 90

🔋 Latent Heat PCM Storage Module & Melting Mushy Zone

Real-time visual simulation: Heat transfer fluid tubes charging the PCM matrix through progressive phase change

📝 Configuration & Presets

☀️ Solar Paraffin Wax (58°C) ❄️ HVAC Salt Hydrate (29.5°C) 🏭 Waste Steam Erythritol (118°C) 🌋 Solar Molten Salt (220°C)
🧪 Phase Change Material (PCM) Selection
⚡ Heat Transfer Fluid (HTF) Charging Loop
Must exceed Tm (220°C)
PCM Thermal Energy Storage Formulation:
• Total Stored Energy: Etot = Mpcm [ cps(Tm−Ti) + Lf + cpl(Tin−Tm) ] / 3600 [kWh]
• Charging Effectiveness: ε = 1 − e−NTU, where NTU = UA / (ṁ · cp,htf)
• Average Charging Power: Q̇avg = ṁ · cp,htf · (Tin − Tm) · ε [kW]
• Total Charging Time: tcharge = Etot / Q̇avg [hours]

📊 Storage Performance Results

📊 Output Summary
💾 Fortran Source

Total Stored Thermal Energy
240.97 kWh
Latent Portion: 111.11 kWh (46.1%) | Charging Power: 171.74 kW
tcharge = 84.2 min
Full Charging Duration 1.40 hours 84 minutes
Average Thermal Power 171.74 kW Charging rate
Heat Exchanger Effectiveness 34.1 % NTU = 0.417
PCM Melting Temperature 220.0 °C Lf = 160 kJ/kg

📈 State of Charge SOC (%) vs Charging Time (hours)

📉 Instantaneous Charging Power Q (kW) vs Time (hours)

=================================================================
 THERMOFLUIDCALC — PCM LATENT HEAT THERMAL STORAGE REPORT
=================================================================
Case Title                 : Concentrated Solar Power Nitrate Molten Salt Module
PCM Material Type          : Solar Nitrate Molten Salt (KNO3-NaNO3)
Storage Sizing             : PCM Mass = 2500.0 kg, Melting Temp Tm = 220.0 C (Lf = 160.0 kJ/kg)
HTF Charging Loop          : Inlet Temp = 280.0 C, Mass Flow = 4.00 kg/s, UA = 3500.0 W/K (NTU = 0.417)
-----------------------------------------------------------------
TOTAL STORED THERMAL ENERGY: 240.97 kWh (867.5 MJ)
 - Latent Heat Portion (Lf): 111.11 kWh (46.1%)
 - Sensible Heat Portion   : 129.86 kWh (53.9%)
AVERAGE CHARGING POWER     : 171.74 kW
TOTAL CHARGING DURATION    : 1.40 hours (84.2 minutes)
=================================================================

📘 Calculation Methodology & Latent Storage Standards

High Energy Density at Constant Temperature

Latent storage absorbs or releases large amounts of thermal energy ($L_f \approx 150 - 350\,\text{kJ/kg}$) at nearly isothermal conditions, offering $3 - 5\times$ higher volumetric energy density than water tanks.

NTU-Effectiveness Charging Model

Computes the transient temperature evolution of the heat transfer fluid as it circulates through embedded finned tubes inside the solidifying or melting PCM core.

Key Engineering Assumptions

  • Enthalpy-based phase change model with well-defined melting point $T_m$.
  • Uniform PCM encapsulation without thermal degradation.
  • Applicable to solar domestic hot water, HVAC peak load shifting, and industrial heat recovery.