# Joukowsky equation

1. Oct 2, 2008

### lambdaLoverD

Hello everyone.
How do you do ! - this is my first post here.

A fluid dynamics question : do you know if the famous Joukowsky equation ($$\Delta P = \rho a \Delta V$$ ) applies to gases too ?

I have found a huge number of publications which mention the Joukowsky equation in relation to water hammer, i.e. the pressure wave(s) generated by a sudden closure of a valve in a water pipe.

On the other hand a similar phenomenon occurs with gases (although the pressure wave has lower amplitude). e.g. steam hammer. But very few publications mention it 0_o.

Does it have another name ? a different mathematical description (since gases are compressible) ?

This paper seems to indicate that the equation works for liquid+gas mixtures
http://www.ipt.ntnu.no/~jsg/publikasjoner/papers2002/Houston2002PressurePulse.pdf [Broken]
But how about gas only ?

Any hint is welcome
Thanks

Last edited by a moderator: May 3, 2017