Good introductory book on fluid dynamics I am interested in getting a good introductory book to fluid dynamics. I am a first year PhD student in Mathematics. 
My project involves a simplification of the Navier-Stokes equations. But I don't have any background whatsoever on fluid dynamics or physics for the matter (at least beyond high school level). 
Thank you for any recommendations! Please don't just post random books you found on Amazon (I can do that myself). I am interested in the opinion of people who have done some fluid dynamics, the more the better, and know about the field. 

"An Introduction to Fluid Dynamics" by G. K. Batchelor is a classic and is considered as the Bhagavad Gita of fluid dynamics. I have read this book as an undergrad and hence the knowledge required is just high school mathematics and physics.
Recent texts, in my opinion, are unfortunately biased too much towards computational fluid dynamics, than explaining the mathematical and physical underpinning of the fluid dynamics.
