The following data was observed for a CI engine: Fuel-air ratio: 0.04, Volumetric efficiency: 85%, Indicated mean effective pressure: 8 bar, Fuel calorific value: 44000 kJ/kg, Density of air: 1 kg/m3. What is the indicated thermal efficiency of this engine?
1
43%
2
64%
3
53%
4
69%