Another pet peeve of mine is the absence of a discussion of why turbulence is a hard problem to solve. The reason is actually quite simple: the computational co

Another pet peeve of mine is the absence of a discussion of why turbulence is a hard problem to solve. The reason is actually quite simple: the computational cost for directly solving the Navier-Stokes equations is far too high. They could have shown this in the video; the estimate is actually rather straightforward. (Estimate the "Kolmogorov scale", the scale of the smallest eddies that need to be resolved, and combine that with the CFL condition to get an upper bound on the stable time step, etc., as I recall.) So in practice people typically solve lower cost (but less accurate) equations derived from the Navier-Stokes equations. They could have briefly described the "closure problem" for this, and maybe some basic turbulence models. Well, they could hypothetically do all this in a future video...