A 3-Litre, four-stroke cycle, CI engine operates at an engine speed of 4000 RPM. It has...

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A 3-Litre, four-stroke cycle, CI engine operates at an engine speed of 4000 RPM. It has a brake specific fuel consumption of 250 g/kW.h. The volumetric efficiency is 90%. The mechanical efficiency is 88%. The light diesel has a heating value of 41,000 kJ/kg. The combustion efficiency is 98%, and the air- fuel ratio is 18. The bore and stroke are related as B=1.2S. The maximum average piston speed is 15 m/s according to the limitation of the new material used in this engine. Determine: (i) The minimum number of cylinders. (ii) Mass flow rate of exhaust flow of the engine. [kg/s] (iii) Indicated thermal efficiency. [%] The manufacturer plans to use this engine to power a pickup truck but finds its power output is insufficient. The design team plans to add a supercharger to the engine to add extra 50 kW brake power to the original engine so that they do not need to re-design the whole engine. The brake specific fuel consumption is now improved to 190 g/kWh, and the air-fuel ratio is increased to AF=19. Determine the volumetric efficiency of the modified engine [%]. A 3-Litre, four-stroke cycle, CI engine operates at an engine speed of 4000 RPM. It has a brake specific fuel consumption of 250 g/kW.h. The volumetric efficiency is 90%. The mechanical efficiency is 88%. The light diesel has a heating value of 41,000 kJ/kg. The combustion efficiency is 98%, and the air- fuel ratio is 18. The bore and stroke are related as B=1.2S. The maximum average piston speed is 15 m/s according to the limitation of the new material used in this engine. Determine: (i) The minimum number of cylinders. (ii) Mass flow rate of exhaust flow of the engine. [kg/s] (iii) Indicated thermal efficiency. [%] The manufacturer plans to use this engine to power a pickup truck but finds its power output is insufficient. The design team plans to add a supercharger to the engine to add extra 50 kW brake power to the original engine so that they do not need to re-design the whole engine. The brake specific fuel consumption is now improved to 190 g/kWh, and the air-fuel ratio is increased to AF=19. Determine the volumetric efficiency of the modified engine [%].

Answer rating: 100% (QA)

i To determine the minimum number of cylinders we need to calculate the displacement volume of the engine Displacement volume 3 L 1000 cm3L 3000 cm3 W... View the full answer