Please go through tutorials for meshing. You are using Ansys Meshing. And you are trying to mesh solids. You do not have fluid volume. You need to create fluid volume in SpaceClaim. For this geometry you need to use Fluent Meshing Fault Tolerant Workflow. Also if you are using student version then you are limited to 512K cells. This geometry will need lot more than that. Please use some simple geometry first and try some tutorials.
Please go through help manual for more details
Regards,
Keyur
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