What are the mesh quality tools in Fluent?

In Fluent, there are several checks you can perform to ensure the quality of your mesh. One of the first steps is to increase the mesh check verbosity using the TUI command/mesh/check-verbosity. Fluent can also attempt to fix the mesh check problems via the TUI command/mesh/repair-improve/repair [1]. URL: [1] https://forum.ansys.com/forums/topic/when-i-open-fluent-and-do-mesh-quality-check-im/

In Ansys Meshing, it's important to ensure the minimum orthogonal quality is above 0.1 to proceed to the solver. If it is below 0.1, the mesh needs improvement. You can identify the locations of the bad elements and consider improving the mesh using different mesh sizing [1].

You can also check the mesh right after reading it into the solver, in order to detect any mesh trouble before you get started with the problem setup. Report Quality displays various quantities related to the quality of the mesh in the console, such as Minimum Orthogonal Quality and Maximum Aspect Ratio [2]. URL: [2] https://ansyshelp.ansys.com/Views/Secured/corp/v232/en/flu_ug/flu_ug_general_task_page.html

When encountering issues with mesh interface selection and floating point exception errors in Fluent, it is recommended to use a conformal mesh unless interfaces are being created for analysis purposes such as MRF or sliding mesh [3]. URL: [3] https://forum.ansys.com/forums/topic/mesh-interface-and-floating-point-exception-error/

To visualize specific cells in Fluent, particularly those with poor mesh quality, cell registers can be created. This can be done by navigating to the Domain Tab, under the Adapt group, and selecting Refine / Coarsen [4]. URL: [4] https://forum.ansys.com/forums/topic/quality-mesh-3/

Lastly, after generating the volume mesh, check the quality of the cells to get an indication of overall mesh quality. The quality of the mesh plays a significant role in the accuracy and stability of the numerical computation. To check cell size and quality limits, use the Report > Cell Limits.. dialog box [5]. URL: [5] https://ansyshelp.ansys.com/Views/Secured/corp/v232/en/flu_ug/tgd_user_report.html

References:
[1] Title: "Addressing Mesh Quality Check Warning in Fluent: Increasing Verbosity, Repairing with TUI Commands, and Improving Mesh Quality", URL: https://forum.ansys.com/forums/topic/when-i-open-fluent-and-do-mesh-quality-check-im/
[2] Title: "48.3. General Task Page", URL: https://ansyshelp.ansys.com/Views/Secured/corp/v232/en/flu_ug/flu_ug_general_task_page.html
[3] Title: "Addressing Mesh Interface Selection and Floating Point Exception Error in Fluent", URL: https://forum.ansys.com/forums/topic/mesh-interface-and-floating-point-exception-error/
[4] Title: "Visualizing and Improving Quality of Specific Cells in Fluent Mesh", URL: https://forum.ansys.com/forums/topic/quality-mesh-3/
[5] Title: "5.3. Determining Mesh Statistics and Quality", URL: https://ansyshelp.ansys.com/Views/Secured/corp/v232/en/flu_ug/tgd_user_report.html