On the critical conditions for determining the speed of sound
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For exhaust pipes, there is a formula to determine the critical condition for the speed of sound; according to this formula, in systems that discharge into the atmosphere, an exhaust pressure of 2 kilograms or more generally indicates that the critical condition has been reached. But this is clearly inconsistent with v=sqrt(2gh). If it is gas being released under a pressure of 2 kilograms, using the formula v=sqrt(2gh), all that pressure is converted into kinetic energy; what is the flow velocity then? But at the critical point, it immediately reaches the speed of sound. How should we understand this? If it reaches the speed of sound, there isn’t actually that much flow in the pipe – does a vacuum form?
I’m not quite sure what you mean. Whether a speed reaches the speed of sound can be determined using the Mach number, which is given by M = V/Vc; a value of 1 corresponds to the speed of sound, while values greater than 1 indicate supersonic speeds. Vc=41*sqrt(k*T*Mw/29). Units: Vc – ft/s; T – R
This post was last edited by mustvictory on 2016-4-1 at 17:10. What you have here is the calculation of sound speed; vc represents sound speed, and there is a formula for determining the threshold value – if it meets that condition, then it’s sound speed