Question

A four-stroke diesel engine operating at 1200 rpm uses 0.1 kg of fuel in 5 minutes and has the brake specific fuel consumption equals to 0.1910 kg\BHP\h. Calculate the torque developed.

(a) 6.5 kg-m

(b) 8 kg-m

(c) 7.5 kg-m

(d) 5 kg-m

This question was addressed to me in a job interview.

Question is taken from I.C. Engine Components topic in section Internal Combustion Engine of Farm Machinery

Answer 1

Right answer is (c) 7.5 kg-m

To explain I would say: N = 1200/2 = 600

BHP = 2πpT/4500

= 0.837T

Break Sp. Fuel Consumption = 0.1*60/0.837T*5

0.1910 = 0.1/0.837T*5

T=7.5 kg-m.