Intro to compressible flow [Aerodynamics #17]

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: sites.udel.edu...

[@phantomimmortal9962]

These have been great to go through!!
A quick typo note: at 16:50 you have s2-s1 = cv ln(T2/T1) - R ln(p2/p1) when I believe it should be s2-s1 = cv ln(T2/T1) + R ln(v2/v1)

[@prof.vanburen]

Yes! You're right, there is a typo here which is corrected in the PDF version of these notes on my site. Unfortunately my typo rate seems strongly correlated with the amount of thermodynamics content there is.

[@yongjianrong8587]

The derivation for Mach number gave me a new deep insight into its meaning, thanks!

[@prof.vanburen]

Glad you liked it!

[@lifeisswel7249]

same here, prof.vanburen

[@andrewbrevick595]

I think your videos are great! One comment is that the variables in equations are sometimes small and tough to read, especially with subscripts. One idea might be to write the equations larger initially, and then shrink them down with your tablet software so they fit better with the notes. Thanks for making this content!

[@prof.vanburen]

Hey thanks for the tip! I might have to try that, writing big and shrinking down. I have sloppy handwriting too, so it's probably double confusing, haha. I will play with pen sizes and see if there's anything better, and try and go a bit more carefully.

[@flth1040]

Explanation at 10:30 is a bit wrong. We are riding on the wave front, fluid on the right seems to move towards us with speed a and on the left, it seems to move away from us with speed a-dv.

[@prof.vanburen]

Thanks for clarifying!

[@DineshSathambakkam]

Thank you so much for the content, it is very useful.

[@prof.vanburen]

You're welcome and glad you like it!

[@mikeshan417]

Hello Prof, could you please do a video on derivation of the conservation of energy equation? I can't find any good ones...

[@prof.vanburen]

Hi Mike! Good idea---let me think about the best way to derive there are a few approaches.

[@mikeshan417]

@@prof.vanburen Many thanks!