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 jinwon park December 16, 2007 14:24

Equation of state for water?

I am solving gas-water compressible flows. In stating the state of water, there are various EOS models. For example, the stiffened-gas equation, the Tait equation, Gruneisen EOS, etc.

There are pros and cons in selecting any of them. Which one is a favorite model you all have used? I prefer to use the stiffened-gas equation because of its simple form which is an extension of ideal gas law.

When I used the stiffend gas equation to describe the state of water, are there any serious cons?

 abouziar December 20, 2007 06:24

Re: Equation of state for water?

For Tait there is Riemann's solver, it is convenient if u use Godunov type scheme, Tait is good for gas and water, for gas it is the same ideal law.

 jinwon December 20, 2007 08:32

Re: Equation of state for water?

Can you confirm that this is an analogy of Tait equation?

p=(gamma-1)*rho*e - gamma*B

where gamma is the ratio of specific heats and B is a constant.

I doubt that the above is the Tait EOS.

In the literature, the Tait EOS is written as

p=B((rho/rho0)^gamma-1.0)+A

Two expressions are using in mixed. Is the Tait EOS you mentioned the second one or the first one? If it is the first one, can you let me know what paper clearly mentions about it?