How to... define motion in Ansys Fluent - sliding mesh

 In many problems that we want to model, we can meet with the movement of one or more elements. This is one of the three methods available from Ansys Fluent. The others are MRF and SRF (multi refernece frame, single reference frame). Sliding mesh is a traffic definition method for transient analyzes. The other methods can be used both in static and transient. They will be described in more detail in the following entries. In this post we will try to show you how to use the sliding mesh method. 

How to add motion on parts in Fluent 

I repeat - this method is used primarily in transient . analyzes. Sliding mesh is used in systems with dynamic features related, for example, to pumping, rapid mass flow generation, turbines or high-speed fans. 

What is sliding mesh method in Fluent?

It is a dynamic simulation over time function, in which the mesh nodes move in next time steps of the simulation with the right body movement.

First U need on the left menu pick Cell Zone  (red frame). Then double click on the domaim which U need define as rotating. After that pick mesh mówiony (green frame) . For the rotating domains U will have two coordinate frames (orange and blue frame). In this post we are interested on self rotatning domain so, we want to rotate domain on its own  axis. We pick rotating  axis  in the blue frame. The Last thing we need to define rotational speed. 

Remember on the post processing to have continous velocity plots U need to pick velocity  in stn  frame 

How to define motion on parts in Fluent 

From personal experience, I can say that defining the movement of objects in Fluent is much easier than in CFX. It can also be said that the solvers used by Fluent are more stable for elements with defined motion (transational or rotational).