Question

Carbon dioxide enters an adiabatic nozzle at 1200 K with a velocity of 75 m/s and leaves at 400 K. Assume constant specific heats at room temperature. Determine the Mach number at the inlet. The gas constant of carbon dioxide is R = 0.1889 kJ/kg·K and k = 1.288. The Mach number at the inlet is

Answer 1

Answer:

The Mach number at the inlet is 0.14

Explanation:

Mach number = v/a

v = 75 m/s

a = sqrt(kRT)

k = 1.288

R = 0.1889 kJ/kg.K = 0.1889×1000 = 188.9 J/kg. K

T = 1200 K

a = sqrt(1.288×188.9×1200) = sqrt(291963.84) = 540.34 m/s

Mach number = 75m/s ÷ 540.34m/s = 0.14