Steam turbine – Work and efficiency calculation

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 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.

Calculations

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

Input data

Output data

References