---
# System prepended metadata

title: Using Fluent in Lochness

---

# Using Fluent in Lochness
To use Fluent in Lochness user needs to set up the case in Fluent installed on the local machine.
If the problem is transient, user needs to select `Calculation Activities`.

![](https://i.imgur.com/g3huFkX.png)

To save the data at a particular time step interval user needs to select *Edit* option in `Autosave Every (Flow Time) [s]` 

![](https://i.imgur.com/Sm7VzPG.png)

In the `File name` option user needs to provide the subdirectory where the data will be saved and the file name. 
For example, in this above figure, `data/spray-geometry` means the fluent data will be saved in the `data` subdirectory and with the filename prefix `spray geometry`. User needs to create the `data` directory under the case directory in Lochness. 

![](https://i.imgur.com/0ccry9K.png)

Similarly, for post-processing, user can export the data in ensight format and can select *Edit* from the `Automatic Export` option.

Once the setup is completed user needs to save the case with data and tranfer `.cas.h5` and `.dat.h5` to Lochness.

To run the fluent cases on Lochness user needs to have journal file. The sample journal file can be found in `/opt/site/examples/fluent/pipe.input.jou`
Here the journal file format is provided for transient case
```
/file/set-tui-version "21.1"
/file/read-case-data spray-geometry.cas.h5
solve/dual-time-iterate 10 50
(print-case-timer)
parallel/timer/usage
```
The job submit script can be found in `/opt/site/examples/fluent_new.submit.sh`

To submit the jib user needs use the following command.
`sbatch fluent_new.submit.sh`

This will generate output file with `.out` extenstion.
To check the output file, use

`tail -f filename.out`

Once the job is finished, user can transfer the output files to local machine and use ParaView or Tecplot to visulaize the data.






