Learning Forum

[Hesam062]

Hi

I am doing multiphase turbulence modeling in Fluent. My question is that why does Fluent just show y-plus not y-star. I saw some videos on YouTube showing both y-plus and y-star options in fluent. I am using dispersed turbulence model.

[DrAmine]

Why are you requiring it? The quantity is required for all near wall modeling inside all multiphase turbulence flavors. Probably not exposed. I will check that.n

[Hesam062]

Actually I am using standard K -epsilon with standard wall treatment and I want to check the y -star or y-plus to be sure about the final result accuracy. Must y-plus be between 30 and 300 when I am applying standard wall treatment to get the reliable result? n

[DrAmine]

You can then just take care about yplus. Yes it should be between 30 and 300 when using the non recommended K-Epsilon Model with Standard Wall Functions. Yplus alone is not important: also the number if layers in the boundary layer is even more important!n

[Hesam062]

I did not get your point. Do you mean the number of layers in boundary layer is important? If so, how can I check it? Or adjust it?nthanks so muchn

[DrAmine]

https://www.computationalfluiddynamics.com.au/y-plus_part3_understanding-impact-of-y-and-number-of-prism-layers-on-flow-resolution/n