In one-dimensional compressible flow, the local speed of sound downstream, often denoted as , refers to the speed at which small disturbances or pressure waves propagate through the fluid in a particular region of the flow. It’s a critical parameter in the analysis of compressible fluid dynamics and is closely related to the local thermodynamic properties of the fluid.
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- is the local speed of sound downstream (at a certain point in the flow).
- is the critical speed of sound, often associated with sonic conditions.
- is the velocity of the fluid downstream.
- is the specific heat ratio