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I’ve been trying to understand shockwaves around an aerofoil from some contour plots I saw here and on the internet, but I’m struggling to understand them

Can someone please recommend a good book on understanding shockwaves (how they form, what they mean, what affects them,…) please?

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    $\begingroup$ Please note that resource location is specifically off-topic. If you can reword this to ask about the subject rather than resource location for the subject I don't see why it would be off topic. $\endgroup$
    – Jamiec ♦
    Commented Apr 17, 2023 at 10:21
  • $\begingroup$ Hi, sorry forgot to write shockwaves around aerofoil, then it’s aviation related $\endgroup$
    – FlightWatcher
    Commented Apr 17, 2023 at 12:16
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    $\begingroup$ It's not that part that makes it off-topic. As I said in my first comment, it's the "resource location" which is off topic. Anyway, looks like you got a good answer, so just for future reference. $\endgroup$
    – Jamiec ♦
    Commented Apr 17, 2023 at 12:34

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Simple shockwaves are best understood starting with (quasi) one-dimensional flow -- flow in a tube. The quasi allows the area of the tube to vary so long as the variation isn't so rapid that the non-axial components of velocity become very important or the variation of properties across the tube become important.

Rocket nozzles (and jet engines) are a great example where quasi 1D flow assumptions are extremely useful.

Any book, course, or set of notes entitled 'Gas Dynamics' should be a good introduction to one-dimensional compressible flow including shocks. One popular text is by James John.

Next, you'll be interested in 2D flow -- there the oblique shock (and conical shocks in 2D axisymmetric flow) come into play. These are also very simple -- you will also learn about expansion fans at this point. This kind of flow is ideal for understanding diamond-shaped supersonic airfoils.

Most aerodynamics books will cover this kind of flow. It would typically be covered in a second course in aerodynamics in a university (so you're looking at the second half of the book).

A great resource that can't be skipped is NACA TR-1135 contains all the formulas and charts you could want for elementary compressible flows. A lot of the textbooks will be dedicated to deriving, explaining, and duplicating what you'll find in 1135.

Once the surfaces are curved -- and/or you are dealing with flow that is not solidly supersonic (i.e. you're in the transonic region). Then the flow becomes much more complex and there aren't any simple answers anymore. I would encourage you to check out Bill Mason's (RIP) notes as a nice overview on the application of transonic flow to airplanes.

Unfortunately, I have a feeling that these kinds of flows (with shocks balanced on the top of a transonic airfoil) are what you are interested in. These are extremely challenging to analyze and design. Fortunately, having a general idea what is going on is much more achievable.

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