Question

Engine manufacturer has provided the reference value of inlet pressure recovery as 0.94. If actual pressure recovery is found to be 0.91 then, find the thrust loss. Consider C of 1.25.

(a) 0.0375

(b) 0.123

(c) 0.0865

(d) 0.568

This question was addressed to me in semester exam.

I'm obligated to ask this question of Propulsion topic in portion Propulsion of Aircraft Design

Answer 1

Correct answer is (a) 0.0375

Explanation: Given, actual inlet pressure recovery p1 = 0.91, reference inlet pressure recovery p = 0.94 and ram recovery Correction factor C=1.25

Now, thrust loss = C*(p-p1)

= 1.25*(0.94-0.91) = 0.0375.