Problem 3: A four-cylinder, four-cycle Diesel engine has a bore and stroke of 30 x 53...

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Problem 3: A four-cylinder, four-cycle Diesel engine has a bore and stroke of 30 x 53 cm and operates at 250 rpm. The fuel is natural gas with a heating value of 36 500 kJ/m, measured at 25C and 1 atm pressure. The theoretical air/fuel ratio is 10.3 m air/m gas. At full load, the engine requires 30% excess air. The indicated thermal efficiency is 27%, and the mechanical efficiency is 78%. Determine (a) the full-load power; (b) the full- load fuel consumption in m/s; (c) the brake mean effective pressure at full load. Problem 4: A Diesel engine having a bore and stroke of 35 x 55 cm with 8 cylinders operates at 250 rpm and produces 746 kW brake power. The fuel consumption is 180 kg/h. The engine's mechanical efficiency is 88%, and the ideal cycle efficiency is 50.5%. Determine (a) the indicated power; (b) the indicated mean effective pressure; (c) the brake engine efficiency; (d) the brake mean effective pressure. Problem 3: A four-cylinder, four-cycle Diesel engine has a bore and stroke of 30 x 53 cm and operates at 250 rpm. The fuel is natural gas with a heating value of 36 500 kJ/m, measured at 25C and 1 atm pressure. The theoretical air/fuel ratio is 10.3 m air/m gas. At full load, the engine requires 30% excess air. The indicated thermal efficiency is 27%, and the mechanical efficiency is 78%. Determine (a) the full-load power; (b) the full- load fuel consumption in m/s; (c) the brake mean effective pressure at full load. Problem 4: A Diesel engine having a bore and stroke of 35 x 55 cm with 8 cylinders operates at 250 rpm and produces 746 kW brake power. The fuel consumption is 180 kg/h. The engine's mechanical efficiency is 88%, and the ideal cycle efficiency is 50.5%. Determine (a) the indicated power; (b) the indicated mean effective pressure; (c) the brake engine efficiency; (d) the brake mean effective pressure.