⚡ Two-Phase Closed Thermosiphon & Heat Pipe Sizer
Size two-phase closed thermosiphons (TPCT) and heat pipes: flooding/entrainment limit, boiling burnout limit, effective thermal conductivity (W/m·K), and temperature drop.
⚡ Fortran 90 Engine
Double Precision (IEEE 754)
✓ ISO / ASME Validated
Heat Exchangers
📊 Solver Telemetry
● ACTIVE
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Hardware & Sizing Partner: Need to size a control valve or check ASME flange bolt torque for this line?
⚡ Two-Phase Evaporation, Vapor Transport & Condensation Loop
Real-time visual simulation: Bottom pool boiling, rising vapor core, top condenser film return📝 Configuration & Presets
☀️ Solar Evacuated Tube
🖥️ CPU Sintered Heat Pipe
🏭 Industrial Waste Heat TPCT
🛰️ Satellite Ammonia Loop
Two-Phase Thermosiphon Formulation:
• Flooding Limit (Wallis/Faghri): Q̇flood = Ck² Av hfg [g·σ·(ρL−ρv)]1/4 [ρv-1/4 + ρL-1/4]-2
• Boiling Burnout Limit: Q̇boiling = 0.18 Ae hfg ρv1/2 [g·σ·(ρL−ρv)]1/4
• Effective Conductivity: keff = (Q̇ · Leff) / (Av · ΔT) >> 100,000 W/(m·K).
• Flooding Limit (Wallis/Faghri): Q̇flood = Ck² Av hfg [g·σ·(ρL−ρv)]1/4 [ρv-1/4 + ρL-1/4]-2
• Boiling Burnout Limit: Q̇boiling = 0.18 Ae hfg ρv1/2 [g·σ·(ρL−ρv)]1/4
• Effective Conductivity: keff = (Q̇ · Leff) / (Av · ΔT) >> 100,000 W/(m·K).
📊 Operating Limits & Results
📊 Output Summary
Maximum Heat Transport Capacity (Q̇max)
4012 W (4.01 kW)
Carried: 1800 W | Critical limit: FLOODING / ENTRAINMENT LIMIT
OPTIMAL SAFE OPERATION
Effective Thermal Conductivity (keff)
105702 W/(m·K)
266x higher than copper
End-to-End Temp Drop (ΔT)
18.8 °C
Nearly isothermal transport
Flooding / Entrainment Limit
4012 W
Vapor-liquid shear threshold
Pool Boiling Burnout Limit
41445 W
Evaporator CHF limit
📈 Max Capacity Qmax (W) vs Vapor Sat Temp Tv (°C)
📊 Effective Conductivity keff [W/(m·K)] vs Heat Load Q (W)
================================================================= THERMOFLUIDCALC — TWO-PHASE CLOSED THERMOSIPHON REPORT ================================================================= Case Title : Industrial Flue Gas Waste Heat Thermosiphon Working Fluid Medium : Ethanol (Non-Toxic Alcohol, 10°C to 120°C) Operating State : Q = 1800.0 W, Tv = 75.0 deg C Thermosiphon Geometry : Do = 38.0 mm, Di = 34.0 mm, Le = 600 mm, La = 400 mm, Lc = 600 mm ----------------------------------------------------------------- MAX HEAT TRANSPORT CAPACITY: 4012.3 W (4.01 kW) Critical Operating Limit : FLOODING / ENTRAINMENT LIMIT Flooding Limit (Wallis) : 4012.3 W Boiling Pool Burnout Limit : 41445.1 W End-to-End Temp Drop (ΔT) : 18.76 deg C EFFECTIVE THERMAL CONDUCT. : 105702 W/(m.K) (Superconductor) SAFETY OPERATING STATUS : OPTIMAL SAFE OPERATION =================================================================
📘 Calculation Methodology & Heat Pipe Standards
Latent Heat Phase-Change Loop
Heat is absorbed by liquid boiling in the evaporator, transported at high speed as vapor along the core, and released by condensation at the cold condenser end, achieving thermal conductivities $100\times$ to $500\times$ higher than solid copper.
Flooding / Entrainment Limit
Occurs when high-velocity upward vapor strips droplets from the downward-returning liquid film, causing evaporator dryout and sharp temperature runaway.
Key Engineering Assumptions
- Gravity-assisted thermosiphon or wick-assisted heat pipe orientation.
- Wallis/Faghri flooding correlation and Kutateladze boiling limit.
- Widely used in solar evacuated tubes, electronics CPU coolers, permafrost ground stabilization, and industrial heat recovery.