The turning moment diagram for a petrol engine is drawn to the following scales: turning moment 1 mm to 2·5 Nm; crank angle, 1 mm to 1°. The fluctuations of energy between the crank positions for minimum and maximum speeds corresponds to an area of 600 mm² of the turning moment diagram. The flywheel is made from cast iron, of density 7·2 tonnes/m3. Determine: (a) The greatest fluctuation of energy (b) The mass of the flywheel required to prevent the a fluctuation of speed greater than ± 0·5% from the mean speed of 1600 rev/min if the radius of gyration is 120 mm. (c) The dimensions of the flywheel (diameter and thickness) (d) Describe the possible consequences to the system if the flywheel was not used to limit the fluctuation of speed.
The turning moment diagram for a petrol engine is drawn to the following scales:
turning moment 1 mm to 2·5 Nm; crank angle, 1 mm to 1°.
The fluctuations of energy between the crank positions for minimum and maximum speeds
corresponds to an area of 600 mm² of the turning moment diagram. The flywheel is made
from cast iron, of density 7·2 tonnes/m3. Determine:
(a) The greatest fluctuation of energy
(b) The mass of the flywheel required to prevent the a fluctuation of speed greater than
± 0·5% from the mean speed of 1600 rev/min if the radius of gyration is 120 mm.
(c) The dimensions of the flywheel (diameter and thickness)
(d) Describe the possible consequences to the system if the flywheel was not used to
limit the fluctuation of speed.
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