[Jiwon Y]

Hello FLUENT experts
I'm a beginner in ANSYS FLUENT and I'm trying to figure out a way to
set a temperature of 40degrees celcius on my fluid(diesel liquid).
Can anyone explain where I can set this option?

It would be great help for me

[AlexanderZ]

solution -> solution initialization

here you may define temperature of the whole model

if you want to define different temperature in specific region of your model than:
- make all settings
- click initialize
- click Patch
here you may select temperature (or any other variable) define value and select zone, where this temperature will be applied.
(for your case select fluid zone)

best regards