Steam turbine – Work and efficiency calculation
Input data
Inlet steam mass flow
Inlet temperature
Inlet pressure
Outlet pressure
Isentropic efficiency
Output data
Work
Outlet vapor quality
Outlet temperature
Description
Calculate the work output of a steam turbine considering its isentropic efficiency. The turbine receives superheated steam, expands it to a lower pressure, and generates mechanical power.
Turbine
The model is based on the First Law of Thermodynamics for steady-flow systems:
$$ \dot{W} = \dot{m} (h_e - h_s) $$ where:
- $\dot{m}$: steam mass flow rate
- $h_e$: inlet steam enthalpy
- $h_s$: outlet steam enthalpy
The real work is obtained through the isentropic efficiency:
$$ \eta_{iso} = \frac{W_{real}}{W_{isent}} $$
Input data
Parameter | Standard units | Description |
|---|---|---|
Inlet steam mass flow | kg/s | Steam mass flow rate entering the turbine |
Inlet temperature | °C | Steam temperature at turbine inlet |
Inlet pressure | bar | Steam pressure at turbine inlet |
Outlet pressure | bar | Steam pressure at turbine exhaust |
Isentropic efficiency | % | Efficiency of the expansion process |
Output data
Parameter | Standard units | Description |
|---|---|---|
Outlet steam mass flow | kg/s | Steam mass flow rate leaving the turbine |
Work | kW | Power developed by the turbine |
Outlet vapor quality | % | Dryness fraction of the outlet steam |
Outlet temperature | °C | Steam temperature at turbine exhaust |
Technical notes:
- Enthalpy and entropy are evaluated using thermodynamic water/steam properties.
- The model assumes adiabatic expansion with negligible heat losses.