# Matlab and the Euler Equations

1. Sep 18, 2006

### H_man

Hi,

I was wondering if Matlab was the sort of program I'd want to solve the Euler Equations (fluid dynamics).

And if it is, I am sure this must be a very standard problem.. does anybody know of any tutorials for this sort of problem as I have never used matlab?

:tongue2:

2. Sep 18, 2006

### Clausius2

What are you solving?

3. Sep 18, 2006

### H_man

Expansion of a gas jet.

From what I know of numerical methods (which is not enough) I think it would be a shame to do it from scratch.

The particular equation takes the form:

$$\nabla\cdot$$(rU)U + $$\nabla p$$ = 0

(for the steady state case)

4. Sep 18, 2006

### Clausius2

You can do almost whatever you want with Matlab. It has a limit in memory though. But for reaching that limit your computation should be very heavy.

What do you mean with the expansion of a gas jet? Don't be afraid about being more explicit, nobody here is going to steal your idea or your project. So please elaborate your answer a little bit more. Even in your post I see the words "jet" and "Euler Equations" which are two totally contradictory statements. They don't get along very well in fluid mechanics.

5. Sep 19, 2006

### H_man

I had in mind playing with the gas expansion problem as a stepping stone to more interesting problems in plasma physics.

With certain simplifications Plasma can be modelled with the Euler equations (see most textbooks on MHD).

6. Sep 19, 2006

### Clausius2

Sure, with certain simplifications Ordinary Fluids can be modelled with the Euler equations too.

As far as ordinary fluids are concerned, even though the core of the jet is at high enough Reynolds numbers to assume Euler approximation, turns out to be that the formation of the mixing layer in the radial limit of the jet influences a lot its dynamics.

That's why I was asking you. Anyway I think you wouldn't have to worry working properly with such rariefied flows.