♻️ Organic Rankine Cycle (ORC)
Analyze ORC systems for low-to-medium temperature waste heat recovery. Compare organic working fluids (R245fa, R134a, n-Pentane, Toluene, R1233zd) and optimize source temperature and superheat.
📝 Configuration
Key Equations:
ηth = Wnet/Qin
ηrelative = ηth/ηCarnot
hfg(T) = hfg(Tb)·((Tc−T)/(Tc−Tb))^0.38 (Watson)
BWR = Wpump/Wturbine
Dry fluid: superheated exit (no moisture)
ηth = Wnet/Qin
ηrelative = ηth/ηCarnot
hfg(T) = hfg(Tb)·((Tc−T)/(Tc−Tb))^0.38 (Watson)
BWR = Wpump/Wturbine
Dry fluid: superheated exit (no moisture)
📊 Results
Configure inputs and click Analyze to view results.
📘 Methodology
Organic Rankine Cycles
ORCs use organic working fluids with low boiling points to convert low-temperature heat (80–350°C) into electricity. Applications include geothermal, solar thermal, waste heat recovery, and biomass. Typical efficiencies range from 5–20%.
Dry vs Wet Fluids
Organic fluids like R245fa and pentane have positive-slope saturation curves (dry fluids), meaning turbine expansion ends in the superheated region—eliminating moisture erosion concerns. This is a key advantage over steam Rankine cycles at low temperatures.
Assumptions
- Simplified constant cp model for liquid and vapor phases.
- Watson correlation for latent heat variation with temperature.
- Clausius-Clapeyron approximation for saturation pressures.
- Steady-state, dry expansion assumed for all fluids.