Learning Forum

[aitor.amatriain]

Hello,

I all books about finite volume method it is said that the central differencing scheme is just the mean between the cells that share a face. However, in Ansys Fluernt there is another term that contains the gradients of the variables:

https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v231/en/flu_th/flu_th_SolveDiscretization_spatial.html?q=central%20differencing

What is the purpose of adding this term? As far as I am concerned, the "standard" expression is also second-order acccurate.

Thank you,

Aitor

[Federico Alzamora Previtali]

Hello, 

the inclusion of the gradient term provides a higher-order correction to the central differencing scheme, enabling Fluent to better capture complex flow phenomena, e.g. steep gradients and/or discontinuities, and deliver improved accuracy compared to the standard approach.