Learning Forum

[Inaam Hussain]

For the Ansys Fluent application tab, I was able to simulate the transonic flow over the circular and square cylinders at different Mach numbers.

In Ansys CFD post, how can I do the following things:

1) Display the Cd change with respect to mach number regarding the square and circular cylinder

2) Display the lift coefficient distribution across the surface regarding the circular and square cylinder

3)Display the drag coefficient distribution across the surface regarding the circular and square cylinder


4) Shock induced separation through velocity streamlines.


For your Information:

I know how to save the Ansys Fluent data and case files in .dat and .cas respectively.

[Inaam Hussain]

If necessary, I'll send out screenshots of my problem.

[Inaam Hussain]

Can anyone respond to me ASAP

[Rob]

Erm, what day was July 8th? What about the 9th? 

You don't display Cd etc as such. The Force reports are in the Results section of Fluent. You'll need to note the values and then plot in Excel or similar. 

In Fluent they're called pathlines rather than streamlines. Use will be covered in one of the tutorials you'll find in the Help system. 

[Inaam Hussain]

Yes, I have just done that, now how to map static pressure and total pressure contours can be mapped in CFD post and how the streamlines (path lines) along shock induced separation flows can be mapped in CFD post?

SHow me how

[Rob]

I'd do all of the post processing in Fluent. Please clarify what you mean by mapped in CFD Post. 

[Inaam Hussain]

Mapping the static pressure contour in CFD post. I mean what is cfd post good for? Drawing x y plots.

 

If I am investigating transonic slow over circular and square cylinders? What xy plots would be relevant

[Rob]

Do you mean plotting? If you're referring to contours etc please review the tutorials. CFD Post was the post processing tool of choice for a few releases but Fluent's built in tools have seen significant improvements over the last several releases. 

I'd use the xy plots that are needed to answer whatever it was I was investigating. That's one to ask your supervisor as I have no idea what they'll be marking you on. 

[Inaam Hussain]

How comes the Ansys 2023 of cfd post doesn't plot up the dynamic pressure?

[Rob]

Because Fluent calculates many fields as they're needed and the .dat file only contains the data Fluent needs to run. For CFD Post use a .cdat with the fields you want, or add additional data to the .dat file. Note Fluent can't read a .cdat file as it doesn't contain what Fluent needs. 

Hence my suggestion to use Fluent post processing for Fluent models. 

[Inaam Hussain]

How do I get high resolution contours from Ansys fluent, without zooming in

[Rob]

You mean banded or you want to see a region closer up? Have you done the Fluent tutorials as the first few cover post processing in some detail. 

[Inaam Hussain]

https://youtu.be/WobfIH7C_FM

how is it my contours doesn't look smooth like this one when I zoom in? It also doesn't look high resolution 

[Rob]

As I don't know what your model looks like it's difficult to guess what the problem is. Maybe post some images?