Find Total force:

A single cylinder vertical engine contains a bore 35 cm and a stroke of 40 cm. The connecting rod is equal to 110 cm long. Mass of reciprocating parts is equal to 140 kg. At the expansion stroke along the crank at 30^o from the TDC, the gas pressure is equal to 0.8 MPa. If engine runs at 260 rpm, find Total force at the piston,

Solution

It is given that:

Piston diameter, d = 35 cm = 0.35 m

Piston stroke, s = 40 cm = 0.4 m

 Length of CR, l = 110 cm

Mass of reciprocating points, 'm' = 140 kg

Pressure in cylinder, 'p' = 0.8 MP_a

Speed, 'N' = 260 rpm

Angle θ = 30^o

        Net Force on the Piston

To calculate Net force on the piston of a vertical engine

P = Gas force ± Inertia force + Load

Gas force = (π/4) d ² p = (π/4) (0.35)² × 0.8 × 10⁶  N   = 76969 N

Inertia force = m ω² r =

 Inertia force = 140 × (27.23)² × 0.2 ( cos 30^o  + (cos 60)/55 ) = 19867 N

Load 'W ' = 140 g = 1373.4 N

Net force on the piston

P = 76969 - 19867 + 1373.4 = 58475 N