Page 192 - 48Fundamentals of Compressible Fluid Mechanics

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)* CHAPTER 9. FANNO FLOW

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Fig. 9.6: The effects of increase of on the Fanno line

9.7.1.2 Supersonic Branch
There are several transitional points that change the pattern on the flow. The point
is the choking point (for the supersonic branch) in which the exit Mach number
reaches to one. The point9 is the maximum possible flow of supersonic flow not
depend on nozzle. The next point, referred here as the critical point,: , is the point
8
in which no supersonic flow is possible in the tube i.e. the shock reaches to the
nozzle. There is another point, ; , in which no supersonic flow is possible in the
entire nozzle–tube system. Between these transitional points the effect parameters
such and mass flow rate, entrance and exit Mach number are discussed.
At the starting point the flow is choked in the nozzle, (to achieve supersonic
flow). The following ranges that has to be discussed which include (see figure 9.8):

0

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The 0- range, the mass flow rate is constant because the flow is choked at the

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