The crank-pin circle radius of a horizontal engine is 300 mm. The mass of the reciprocating parts is 250 kg. When the crank has travelled 30° from T.D.C., the difference between the driving and the back pressures is 0.45 N/mm2. The connecting rod length between centres is 1.2 m and the cylinder bore is 0.5 m. If the engine runs at 250 r.p.m. and if the effect of piston rod diameter is neglected, calculate the net load on piston.

The crank-pin circle radius of a horizontal engine is 300 mm. The mass of the reciprocating parts is 250 kg. When the crank has travelled 30° from T.D.C., the difference between the driving and the back pressures is 0.45 N/mm2. The connecting rod length between centres is 1.2 m and the cylinder bore is 0.5 m. If the engine runs at 250 r.p.m. and if the effect of piston rod diameter is neglected, calculate the net load on piston. Correct Answer 88357 N

Net piston load is given by F(l) = (p1-p2)πD2÷4 p1-p2 = 0.45 N/mm2 D = 500 mm Therefore F(l) = 88357 N.

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