# Operation of a Throttling Valve

Requires a Wolfram Notebook System

Interact on desktop, mobile and cloud with the free Wolfram Player or other Wolfram Language products.

Propylene gas at 100 bar and 373.15 K is throttled to a lower pressure selected by the slider. The process does not produce any shaft work. In addition, there are no appreciable changes in the kinetic or potential energies. Thus, if the process is adiabatic, we get a reduction of pressure at constant enthalpy (or ). This means that for an ideal gas , since the enthalpy of an ideal gas is a function of temperature only. For most real gases, a reduction in pressure at constant enthalpy leads to a reduction in temperature (i.e. ). Indeed, this situation corresponds to a positive Joule–Thompson coefficient, .

[more]
Contributed by: Housam Binous and Ahmed Bellagi (December 2016)

Open content licensed under CC BY-NC-SA

## Snapshots

## Details

References

[1] J. M. Smith, H. C. Van Ness and M. M. Abbott, *Introduction to Chemical Engineering Thermodynamics*, 7th ed., Boston: McGraw-Hill, 2005.

[2] Aspentech. "Aspen-HYSYS." (Dec 15, 2016) www.aspentech.com/products/aspen-hysys.

## Permanent Citation

"Operation of a Throttling Valve"

http://demonstrations.wolfram.com/OperationOfAThrottlingValve/

Wolfram Demonstrations Project

Published: December 19 2016