Advanced 3D modeling software such as Solidworks can perform stress analysis simulations as well as FEA simulations to highlight issues that may be in flow paths, and can even approximate flow rates in ports based on size and shape and other parameters embedded into the model. It also allows you to create assemblies from numerous parts you created, like a complete engine and show simulations of all the parts moving together to evaluate stress in the individual parts and as a complete assembly. Other 3D modeling software can as well, but Solidworks is an engineering standard for 3D modeling software the world over. My package cost a little over $20K 15 years ago, if that gives you an idea about its capabilities.
