Page 108 - 48Fundamentals of Compressible Fluid Mechanics

70 CHAPTER 4. ISENTROPIC VARIABLE AREA FLOW

The critical ratio of the pressure is

(4.125)

this ratio approach

or more generally when
When
e (4.126)

To obtain the relationship between the temperature and pressure, equation
(4.116) can be integrated

(4.127)

The power of the pressure ratio is approaching when z approach 1. Note that

%
(4.128)

%

The Mach number at every point at the nozzle can be expressed as

(4.129)

&

the Mach number is
(

For
(4.130)

The pressure ratio at any point can be expressed as function of the Mach number

as

,

(4.131)

e (4.132)
for

The critical temperature is given by !

(4.133)

!