0
Problem on Mach angle and Mach number

An Aero-plane travels in air of pressure of 1 bar at 10 degree celsuis at a speed of 1800 km/hr. Find the Mach number and Mach angle. Take k=1.4 and R=287 J/Kg K.

(8 Marks)

Subject Fluid Mechanics 2

Topic Compressible Flow

Difficulty Medium

0  upvotes
0

Given :

Pressure = 1 bar

Temperature t = 10˚ C

T = 10 + 273 = 283 k

Speed V = 1800 km/hr

= $\frac{1800 \times 1000}{60 \times 60} = 500m/s$

K = 1.4

R = 287 J/kg K.

Now, For adiabatic process, the velocity of sound is,

$C = \sqrt{KRT} = \sqrt{1.4 \times 287 \times 283}$

C = 337.20 m/s.

$\therefore$ Mach Number = $\frac{v}{c} = \frac{500}{337.20} = 1.48$

and, Mach angle is, Sin $\alpha$ $\frac{c}{v} = \frac{1}{m}$

$\therefore \alpha = sin^{-1} (\frac{1}{1.48})$

Mach angle is $\alpha = 42.40˚$

0  upvotes
Please log in to add an answer.

Next up

Read More Questions

If you are looking for answer to specific questions, you can search them here. We'll find the best answer for you.

Search

Study Full Subject

If you are looking for good study material, you can checkout our subjects. Hundreds of important topics are covered in them.

Know More