Learning Forum

[Mac123]

Hello

So the discretized-- it's got a good initial guess and now it'll use the second order discretization-- the linearized equations that come from that-- to tweak the cell center values.

What does this statement exactly mean ?

It is a bit confusing

Regards

[RK]

Hello, 

What is it in context to?

[Mac123]

Hello Rahul

This statement has been made regarding the analysis of an airfoil 

using fluent.

[Mac123]

What exactly is the difference between first order and second order discretization ?

[RK]

Hello, 

In general, the order of schemes is dependent on the number of grid points used to calculate the flow property at a particular point in the flowfield. 

Second order schemes are more accurate than first order schemes, but they are numerically less diffusive than first order which may sometimes lead to instability in the solution. For a certain type of flows, for example, high Mach number flows, it is suggested to start off with a first order scheme which is relatively easy to converge and then switch to second order scheme for better accuracy. 

For more information, please refer to the link:

 https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v201/en/flu_ug/x1-174200027.2.1.html?q=first%20order%20second%20order