The quality is really bad. You can improve it using Fluent Meshing as follows.
Please open Fluent in Meshing Mode.
Go to Mesh --> Tools --> Auto Node Move
Set Quality Measure as Inverse Ortho
Select all boundary zones.
Use 5 iterations
Save .msh file and read in Fluent.
As you are using Workbench meshing, you need to find out where these low quality elements are. Please select orthogonal quality and plot histogram. Then you can click in histogram to see bad elements in the graphics. Then you may need to modify the geometry in SpaceClaim or use virtual topology in Meshing or may be use local sizing to refine the mesh further. Once done, generate mesh and check the quality before proceed.
Check following video which may help.
Hope this helps.