blob: d2390aa68377067d7cdbb50e589b95a06688cfd9 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
|
clc
// Example 4.6.py
// Consider a 15 deg half angle wedge at zero angle of attack in a Mach 3 flow of
// air. Calculate the drag coefficient. Assume that the pressure exerted over the
// base of the wedge, the base pressure, is equal to the free stream pressure.
// Variable declaration
M1 = 3.0 // upstream mach number
theta = 15.0 // deflection (in degrees)
gamma1 = 1.4 // ratio of specific heats
// Calculations
// subscript 2 means behind the shock
// from figure 4.5 from M1 = 3.0, theta = 15.0 deg.
beta1 = 32.2 // shock angle (in degress)
// degree to radian conversion is done by multiplying by %pi/180
//
Mn1 = M1 * sin(beta1*%pi/180) // upstream mach number normal to the shock
// from Table A2 for Mn1 = 1.6
p2_by_p1 = 2.82 // p2/p1
cd1 = 4/(gamma1*M1*M1)*(p2_by_p1 - 1)*tan(theta*%pi/180)
// Results
printf("\n Coefficient of drag is %.3f",(cd1))
|
