In this lecture, we pivot from incompressible flows and start fresh with compressible flows. Flows become compressible when you either go really fast, or really high up (low density = low speed of sound). Most of the equations we've learned past the conservation laws required incompressible flow, so they are no longer useful in this part of the course. We go over the physical aspects of compressible flow and why the Mach number is so important. Then, we review our conservation equations and refresh some thermodynamics tools that we will use moving forward.

Free downloadable notes (PDF with white background) can be found at my website: https://sites.udel.edu/vanburen/educa...