Subtopic: I.C. engine systems – fuel, cooling, lubrication, ignition, electrical, intake and exhaust
Question Statement:
A single-cylinder four-stroke diesel engine running at $1500\text{ rpm}$ consumes fuel at a rate of $2.7\text{ kg/h}$. The fuel density is $850\text{ kg/m}^3$. Calculate the volume of fuel injected per power stroke in $\text{mm}^3$ (round off to 1 decimal place).
Answer Key:
70.6
Step-by-Step Solution & Explanation
Number of power strokes per minute for a 4-stroke engine:
$n = \frac{N}{2} = \frac{1500}{2} = 750\text{ strokes/min} = 45000\text{ strokes/h}$
Fuel mass injected per stroke:
$m_s = \frac{2.7\text{ kg/h}}{45000\text{ strokes/h}} = 6.0 \times 10^{-5}\text{ kg} = 0.060\text{ g}$
Volume of fuel per stroke:
$V_s = \frac{m_s}{\rho} = \frac{6.0 \times 10^{-5}\text{ kg}}{850\text{ kg/m}^3} = 7.0588 \times 10^{-8}\text{ m}^3 = 70.59\text{ mm}^3$
Acceptable range: $69.0 - 72.0\text{ mm}^3$.