Generalized Compressibility Chart
Reduced Pressure, Pr = P/Pc
The Generalized Compressibility Chart
Reduced
Temperature
Tr = T/Tc
Ch2, Lesson E, Page 11 - Generalized Compressibility Chart
- Agggghhh ! I warned you it was a scary looking chart !
- This chart is the low-pressure chart, for reduced pressures between 0 and 1 as you can see on the x-axis.
- Z is plotted on the y-axis.
- The solid curves on this diagram are the family of curves for constant reduced temperature. These curves generally run from the upper left-hand corner downwards and towards the right-hand edge of the diagram.
- You can tell the solid curves represent constant TR by reading the labels on the curves for TR = 1.0 and TR = 5.0 highlighted on the chart with yellow circles.
- The dashed curves on this diagram are the family of curves for constant ideal reduced molar volume.
- You can tell the dashed curves represent constant VR-ideal by reading the label on the curve for VR-ideal = 0.07, highlighted on the chart with a light blue circle.
- Inset on this diagram and highlighted in pale green is a very handy enlargement of the top corner of the chart, where reduced pressure is between 0 and 0.1.
- Hopefully, once you understand how to read this chart, you will be able to tackle the other 2 on your own.
- Reading the generalized compressibility charts and USING them to solve problems are two different things !
- The best way to teach you to read these charts is to SHOW you ! That is the purpose of the example that appears on the following page.
- That example will conclude our discussion of the ideal gas EOS and the Generalized Compressibility EOS.
- Be sure to try the quiz to make sure you really understand all of this material !
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