Learning Forum

[Abhi1311]

Greetings!

I have to compare a couple of results and make a graph out of them but when i use the chart option in ansys post processing it does not give me presentable and easily understandable result. I want to plot my own graph so if i have multiple simulation results of 5 second each then how can i find certain values like temperature, pressure on specific time period say at 1 second, 2 second and so on.

 

[Rob]

If you use monitors as you run the model it'll record value v time if you output the data. Or you can open a data file afterwards and use an xy plot, if you look on the panel there's an option to write the data out too. Multiple xy plot files can then be read into Fluent or Excel to plot a comparison. 

[Abhi1311]

Thank you for your reply.

a. I need to extract information like temperature with respect to time to plot in a plotting software.

b. When i use xy plot afterwards i can't find the option where i can put time as x variable, only instance i get time as a selectable option is when I've already generated streamline and the option that is then available is "time on streamline 1"

c. can you please explain me in brief how to approach this problem?

[Rob]

If you want temperature with time you need to set a monitor point up and save this data as you run the calculation. The file you save can include the flow time and several solver variables: look at the report definition section of the tree. 

 

[Rob]

If it's transient data you're plotting against time. If you want position (say on a line) you'll need to set this when you create the report. Lines can be created in the Results - Surface - Create part of the ribbon menu bar. 

[Abhi1311]

But what if i already have my results with me? Actually i don't have enough time to run all calculations again. Although i had enabled auto-save case files at every .5 second so do you think it will help me in post processing?

[Rob]

If that's the case you'll need to create the point and then generate the value from each data file. Assuming the case file is the same it's just a case of reading in the data & post-processing each model. I'd use a journal for that, but depending on the amount of data & number of files you may be quicker doing it manually. 

[Abhi1311]

Yes the case file is the same but can you explain briefly what to do in post processing, it will be a great help!

Regards

Abhishek

[Rob]

You need some data: could be a single point value or xy-plot of something (position v whatever). Set this up in the case file with a data file loaded. Save the case with a different name (it's always a good idea not to overwrite files). 

Get the numbers you want for that time step & save/export/write down. Read in the next data file & repeat. Do this for as many files as you need.  I'd use a TUI journal for this, but I know how to write them: it's covered in the User's Guide (Journals and TUI operation) if you want to try it. 

Excel can read in text files so you can write out several xy plots (look in the panel for the "write" button) and then plot as desired.