Page 146 - 48Fundamentals of Compressible Fluid Mechanics

108 CHAPTER 6. NORMAL SHOCK IN VARIABLE DUCT AREAS

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Since the stagnation pressure is constant as well the stagnation tempera-
ture, the exit conditions can be calculated.

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The exit temperature is

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For the “critical” points ”a” and ”b” are the points that the shock doesn’t
occur and yet the flow achieve Mach equal 1 at the throat. In that case we don’t
have to go through that shock transition. Yet we have to pay attention that there
two possible back pressures that can “achieve” it or target. The area ratio for both
cases, is
In the subsonic branch (either using equation or the isentropic

Table or GDC-Potto as

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For the supersonic sonic branch

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