# Steam Turbine

Under construction.

## Performance

The following performance calculations are applied to all turbine instances.

Calculation |
Reference |
Output Tags |

Efficiency | ASME PTC 6, S 5.10 | .stageEfficiency.use |

Pressure Drop | .c1.dP.use |

## Calculations

**Turbine Stage Efficiency**

$$\eta _{turb} = \frac{H_{i} - H_{o}}{H_{i} - H_{o} \ _{isentropic}}$$

Where:

- $\eta _{turb}$ = Turbine stage efficiency
- $H_{i}$ = Inlet enthalpy
- $H_{o}$ = Outlet enthalpy
- $H_{o} \ _{isentropic}$ = Calculated enthalpy for isentropic expansion

In CAS terms (where ”.” represents the turbine stage in question):

Turbine stage efficiency (%) =

$$\frac{.c1in.prop.energy.use - .c1out.prop.energy.use}{\left ( .c1in.prop.energy.use - ANYPS2H\left ( .c1out.prop.press.use,.c1in.prop.entropy.use \right ) \right )}$$

**Wet Turbine Stage Efficiency**

$$\eta _{turbwet} = \eta _{turb} \times (1 - B_{f} \times \left ( \frac{w_{i} + w_{o}}{2} \right ))$$

Where:

- $\eta _{turbwet}$ = Wet stage efficiency
- $B_{f}$ = Bauman factor
- $w_{i}$ = Inlet wetness
- $w_{o}$ = Outlet wetness

In CAS terms (where “stage” is the turbine stage in question):

$$stage.wetStageEfficiency.use = stage.stageEfficiency.use \times (1 - stage.baumanFactor.use \times \left ( \frac{stage.c1in.prop.quality.use + stage.c1out.prop.quality.use}{2} \right ))$$

Wet Stage Efficiency Calculation provided by the book “Wet-steam turbines for nuclear power plants” by Alexander Leyzerovich. Equation 2.1. Note that the bauman factor is usually 1 as mentioned in the reference.

**Turbine Steam Pressure Drop**

$$\Delta P = P_{i} - P_{o}$$

Where:

- $\Delta P$ = Delta pressure (kPa)
- $P_{i}$ = Inlet stage pressure (kPa)
- $P_{o}$ = Outlet stage pressure (kPa)

In CAS terms:

$$turb.c1.cP.use = turb.c1in.prop.press.use - turb.c1out.prop.press.use$$