A question in Dsmc modeling
 

Hello there,
Is there anyone who works in DSMC field?
I am working with DS3V free software which is written by G.A.BIRD, but have some problems for modeling a body. Is there anyone who can help me please?

Dsmc
 

Does any one know softwares that work with dsmc simulations like dsmcfoam ?
Best Regards.

Hello MHP,

did you solve your problem with the DS3V software? What version do you have and does it work correctly? When I'm doing the example with D3SV and close the window for checking the geometry the whole programm is closed...I don't know how to avoid this phenomenon.

Can anybody help?

Best regards
CFDNewbie147

Dear CFDnewbie147,
Yes, I solved my problem last year.
I used the latest version in the Bird's web page.
In my opinion DS3V is not a well stable software, in some cases it may be OK but sometimes it may be disappointing.
If possible specify your problem more clearly, maybe I can help you.

Dear MHP,

thank's for answering.
Oh you're right, it's not very stable.

I would try to use it for a complex 3D reentry-simulation. So i have the geometry as an CAD-file and I want to dictate the temperature of the flow and the mach number. I want to get the aero-coefficient and look how much the surface is heaten up.

Can you help me?

Best regards
CFDNewbie147

In my opinion fortunately reentry simulation by DS3V would result in good conclusion than any other cases. I think there was an example in reentry object simulation in the Bird's web page.
If you want to start with DS3V I recommend to read its manual precisely. You should first discrete any faces of your object with some softwares like Rhinoceros then import the mesh data in DS3V. While generating the initial conditions for each face you will find blanks to fill data like mach number and temperature of the flow.
In the output files there are enough results presents to calculate aero-coefficient.
You would find the answer of major part of your problems in the manual of DS3V presented in the Bird's site.
Good luck.

Dear MHP,

Thank you for the information. I already have the DS3V software but unfortunately the example doesn't work.

Do you have experience with this Rhinoceros software to make meshes? Which datafiles do I have to use for this tool?
I hope you can help again.

Best regards
CFDNewbie147

Dear CFDNewbie147

I will be glad to help you but It is almost one year that I didn't work with Rhino and DS3V and I hardly remember details to work with them. It would be better for you to contact with Prof. Bird if possible.
Usually the DS3V program stops without notification if there is an error in the flow definition files. If I remember correctly, there is a mistake in the delta wing flow case that is available for download on the website. I would recommend you to run the DS3V program for a different case (see surface and flow definition files enclosed in the attachment), this should work.
Fortunately Rhino has a good help. All I find in the Rhino is from its good help. I'm sure that you would find your answers in it's help in the category of mesh.You should save your mesh file as ".raw" format. It is said in the manual of DS3V. Again as a note I strongly recommend to read and use DS3V manual part by part and step by step.

Good luck.

Dear MHP,

sorry for answering so late...I tried your example and it works...but now I have to check what are the parameteres in pre- and post-processing...

I already contacted Mr. Bird but he could'nt help me because he has a lot to do:/

Thank u again, I'm coming back to post if there's something new :)

Dear CFDNewbie147

In post processing many important parameters in DSMC are available overally in graphic user interface that is presented in the DS3V software and in detail in the two .txt files presented in the corresponding folder of your project.

Good luck.

Hi there, I'm working in DSMC. Till now i was working in 2D simulation and i'm planning to develop a 3D algorithm. Is any 3D open source program available for ref??

hello CFDnewbie147 and MHP:
I am new in DS3V program, and meet much problem, please help me, thanks! here are some problem that I have meet this days and nobody used this program before that around me.
1.I want to simulate the molecular contamination in a vaccum chamber to know the molecular diffuse in vaccum environment. the question is that how to set the initial status of vaccum chamber?
2.when i finish the set of the DS3V program, there are not plots in my program's window. there is nothing if I prss"Pause Program for Detail Plot". But when I run the samples that doneload from the internet, the problem miss.
3.I want to supply some gas to the vaccum chamber and how can I set in this program?
sorry for my poor english.
I am looking forward to hearing from you two, thanks a lot!
Best regards
Liaofengmao

How do I obtain this text file ?
I want to set an interval of time after every certain number of timesteps. How to do it.