Question

Find the diameter ratio of an engine which has mach number of 0.7. Consider isentropic flow.

(a) 1.045

(b) 2.045

(c) 3.45

(d) 5.64

The question was asked in an online quiz.

This interesting question is from Propulsion in portion Propulsion and Fuel System Integration of Aircraft Design

Answer 1

The correct option is (a) 1.045

The explanation is: Given, Mach number M = 0.7

Now, for Mach number 0.7 area ratio is 1.094.

Now, diameter ratio is given by,

Diameter ratio = (area ratio)^0.5 = 1.094^0.5 = 1.045.