[waynezw0618]

i am just begining to study the Openfoam.i am interested in spray break up and Atomization.i find the example (http://www.opencfd.co.uk/solutions/examples16.html), which use LESmodels + interface capturing ,is very interesting ,but can anybody give me a tutorial of that.more information and paper are pretty good !!

thanks!

[aderliner]

Hi

It looks like that we are interested in the same thing. Maybe, we could talk about it.
My email is wab_1982@yahoo.com.cn. Or, if you are a Chinese, my qq is 85493011, it may be more convenient.

thanks~!

Bobby

[eugene]

I did the calculation you are referring to. There is already a tutorial example (albeit 2D) in OpenFOAM for this solver:
/users/gaia/software/OpenFOAM/OpenFOAM-1.3/tutorials/lesInterFoam/nozzleFlow2D

There are also two papers covering the use for diesel atomisation. One was published in a SAE compendium (and is quite hard to get hold of) and the other was presented at a conference in Japan and can be downloaded from here:
powerlab.mech.okayama-u.ac.jp/~esd/comodia2004/B4_4_079.pdf

In addition, there is some information on the methodology in the theses by Henrik Rusche and Onno Ubink, although it is by no means comprehensive.

I also suggest you search these forums, as the topic has been discussed at length in the past.

[waynezw0618]

bobby, my QQ has been stolen last week,do you have MSN?
mine is waynezw0618@hotmail.com

[waynezw0618]

to Eugene de Villiers:
thanks,
could you please tell me the title/Author/ of the paper which published on SAE?

[eugene]

Er, yes I am the author.

The SAE paper is here:
http://www.sae.org/technical/papers/2004-01-0100

[aderliner]

to Eugene de Villiers:

Hi~~
I've read your paper in SAE, I wonder if you can tell me how to create a 3D case in FOAM, because there is almost noting about 3D case in userguider(maybe I don't find it, could you tell me?) and it seems like that LES model is not appropriate for the 2D case.
Also, I want to know how to add variable "T" to the case.
Thanks a lot~!
Best regards~!

Bobby

my email:wab_1982@yahoo.com.cn
msn:wab_1982@yahoo.com.cn

[kumar]

Hello Eugene de villiers,
I read your paper Large eddy simulation of primary Diesel spray Atomization,

I am trying to solve a similar problem, where I am taking in all the properties of diesel and air from your paper. My mesh is only slightly different from yours., in my mesh I have a channel which is then continued by the chamber. My pressure, gamma and U boundary conditions are as follows:

gamma :
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions [0 0 0 0 0 0 0];

internalField uniform 0;

boundaryField
{
inlet
{
type fixedValue;
value uniform 1;
}
outlet
{
type inletOutlet;
inletValue uniform 0;
value uniform 0;
}
channelWalls
{
type zeroGradient;
}
walls
{
type zeroGradient;
}
sides
{
type symmetryPlane;
}
frontBack
{
type cyclic;
value uniform 0;
}
}


// ************************************************** *********************** //
Pressure:

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions [1 -1 -2 0 0 0 0];

internalField uniform 0;

boundaryField
{
inlet
{
type fixedValue;
value uniform 190e5;
}
outlet
{
type fixedValue;
value uniform 0;
}
channelWalls
{
type zeroGradient;
}
walls
{
type zeroGradient;
}
sides
{
type symmetryPlane;
}
frontBack
{
type cyclic;
value uniform 0;
}
}


// ************************************************** *********************** //

U b.cs are as follows

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions [0 1 -1 0 0 0 0];

internalField uniform (0 0 0);

boundaryField
{
inlet
{
type pressureInletUniformVelocity;
phi phi;
rho rho;
value uniform (0 0 0);
}
outlet
{
type pressureInletOutletVelocity;
phi phi;
rho rho;
value uniform (0 0 0);
}
channelWalls
{
type fixedValue;
value uniform (0 0 0);
}
walls
{
type fixedValue;
value uniform (0 0 0);
}
sides
{
type symmetryPlane;
}
frontBack
{
type cyclic;
value uniform (0 0 0);
}
}


// ************************************************** *********************** //

As you can see from the b.c,s I have a channeland the chamber into which my fluid gets injected. But i specify only the pressure at the inlet and not the velocity.

I am not able to achieve the convergence for this case with all other settings as the tutorial case.
Iy you are interested, i can send you the controldict as well. My pressure equation falls only to the order of 1e-5 though I specify 1e-7 as my convergence criteria. Even if i increase the number of iterations three times more than the one specified in the tutorial i dont see much improvement in the convergence.

I need some help in understanding the other parameters, inorder to make my pressure equation converge.
any suggestions will be very useful

you can also contact me on my email i.d kumar.kannan@uni.lu
if you dont get the idea how my mesh is it is exactly similar to the one in your paper, but mine is a 2D with only one cell in the z direction and it is a rectangular domain.
the inlet and channel walls are exactly similar to the one in the paper and the walls are the one which form the top shoulder of the chamber. the sides are the one which form the lateral sides of the chamber. the outlet is exactls similar to yours.

bye
with regards
K.Suresh kumar
bye

[hamcer]

Hi foamers!

I m looking for an awisymetric case with a RANS tubulence model , I have already investegated the Lesinterfoam, and rasinterfoam , but, they are not helpfull for me.

some advices will be welcom.