An 8-cylinder (k = 8), 4-stroke cycle, petrol engine with a compression ratio of 11 must be designed to produce 70 kW of brake power (W,) with a torque ( 7) of 200 N•m. At these conditions, all kind...

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Extracted text: An 8-cylinder (k = 8), 4-stroke cycle, petrol engine with a compression ratio of 11 must be designed to produce 70 kW of brake power (W,) with a torque ( 7) of 200 N•m. At these conditions, all kind of mechanical losses are 22%, and the brake mean effective pressure (Pom) is 555 kN/m?. For the air-standard cycle, P1 = 101.325 kN/m², T = 310 K, and y= 1.4. The indicated fuel flow rate (i.e., sfcind) 0.401 kg/(kW•h), where the power is indicated power(Wina) and the fuel has a lower heating value (LHV) of 44000 kJ/kg. The ratio of the piston bore (D) to stroke (L) is 1.20. Deter- mine: (a) The bore (D) and stroke (L), both in cm. (b) The indicated thermal efficiency(17Th, ind) - (c) The brake engine efficiency (7).