WaterSteamPro(R) Sample

Expansion process calculation

Annotation

In this file you find the example of usage functions for calculating properties of water and steam for calculating process of steam expansion in turbine.

About WaterSteamPro

WaterSteamPro is a certified program for calculating properties of water and steam.
Additional information about WaterSteamPro given in it's documentation.
New versions and online documentation available in the www-site of the WaterSteamPro: http://twt.mpei.ac.ru/orlov/watersteampro

Import units definitions and WaterSteamPro dimensions functions

Source data

Find the parameters of steam at the end of expansion process in turbine from parameters: pressure p0 and temperature t0 to pressure p1 with internal relative efficiency of process hoi.

Values:

Solution #1 (with functions of the WaterSteamPro available in demo-version)

1. Parameters in initial point

• specific enthalpy:

• specific entropy:

2. Find a temperature at the end of adiabatic process (without energy loss)

For finding the temperature will use the Mathcad solver block: Given ... Find.
The source equation for the Given ... Find block will be the fact that the specific entropy at the start of process equal the specific entropy at the end of process.

The initial value for the Given ... Find block:

3. Parameters at the end of adiabatic process (without energy loss)

• specific enthalpy:

• specific entropy:

4. Specific enthalpy at the end of real processes (with energy loss)

Find a value from the definition of the internal relative efficiency of process:

5. Find a temperature at the end of real process (with energy loss)

For finding the temperature will use the Mathcad solver block: Given ... Find. We know the values of pressure and specific enthalpy at the end process.

The initial value for the Given ... Find block:

6. Parameters at the end of process

• specific entropy:

7. Create the graph of process in the h-s diagramm

Solution #2 (with the functions for calculating processes of expansion/compression)

1. Parameters in initial point

• specific enthalpy:

• specific entropy:

2. Parameters at the end of real process (with energy loss)

For determining of the parameters will use the functions of the WaterSteamPro for calculating processes of expansion/compression.
These functions require a value of internal relative efficience.

• temperature:

• specific enthalpy:

• specific entropy:

3. Create the graph of process in the h-s diagramm

Comparison of the results

1. Temperature

2. Specific enthalpy

3. Specific entropy