Page 292 - 48Fundamentals of Compressible Fluid Mechanics

254 CHAPTER 14. PRANDTL-MEYER FUNCTION
14.7 Examples

Example 14.1:
A wall is include with inclination. A
flow of air with temperature of flows (see Figure
14.9). Calculate the pressure reduction ratio, and Mach number after the bending
and speed of "
what

will the width of this imaginary tunnel after the bend? Calculate the “fan” angle.
$

Assume the specific heat ratio is >@? . A
point. If the air flows in a imaginary 2-dimensional tunnel with width of 0.1
(

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/10
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Fig. 14.9: The schematic of the Example 14.1 *,+.-

SOLUTION
First the initial Mach number has to calculated (the initial speed of sound).

K

NM
IJ L $
,

This Mach number associated with S T
H
The Mach number is then

O
*

P
PRQ K U J I JI
The “new” angle should be S Q T Q

U
U

and results in * VU KXW U K