Dynamic Meshing with Flow 3D
 

I need to model a gear pump and realized that it needs a dynamic meshing approach. Is Flow 3D capable of unstructured dynamic meshing

No, it doesn't, but it's not needed. The general moving object model in FLOW-3D allows you to model rigid bodies moving in the structured, fixed mesh, with both prescribed user-prescribed motion, or dynamically coupled with the fluid flow. Visit this page for a little more information (there's a gear example given), or contact Flow Science.