So, speaking theoretically, if you could accelerate a fluid to extreme Mach number at sea level, then at what point does the Navier Stokes number lose its validity? What equations would you then use to model this potentially extreme momentum?(adsbygoogle = window.adsbygoogle || []).push({});

I presume based on the fact that Newton's Law's are an approximation to the classical world that only really fail at extreme velocities approaching the speed of light, how close to those velocities do we need to be before we need to worry about the validity of the equations and can we apply corrections to N-S to correct for this?

Finally, is it theoretically possible to collect a group of neutrino's for instance, compact them so that they can regarded as a continuum (very low Knudsen number) and therefore model this from using what we've just discussed?

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# Validity of Navier-Stokes at Extreme Mach Nos. (M = 100,000)

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