5.4.3. Summary z The engine output depends upon the supplied fuel quantity and the engine efficiency. In order to transform into the effective work of engine by burning the supplied fuel fully, the sufficient air to burn the fuel should be supplied to the cylinder. Therefore, the engine output is essentially determined by the size of the cylinder, and for if the air is supplied to the given volume of cylinder with the air being compressed, the air quantity in the cylinder will Increase as much to result in that it may burn more fuel.
the output will also be able to increase, Supplying the air by compressing like this into the engine cylinder is called as super charging, and super charging by means of exhaust gas energy that discharges to the atmosphere is called as the turbo charging. 5.4.4. Function 1) Turbine The exhaust gas that is discharged from combustion chamber passes through turbine housing conveying an energy to turbine wings to give the rotating power, This is called as the turbine and in order not to influence a bad effect at bearing part, there are the seal ring and heat dissipator.
2) Compressor It is connected to the same shaft with the turbine to make a revolving assembly, and receive the revolving force of turbine, and sends air to the suction manifold by suctioning and compressing it. This is called as the compressor. 3) Bearing z Thrust bearing force is applied to the turbine wheel and an arrangement is made for the shaft not to shift.
z Journal bearing (floating bearing) is adopted and it forms the double oil films at the in out surfaces in comparison to the general stationary type so that the bearing may be able to rotate independently and consequently the double layers of films act as the damper to make the slipping speed on the bearing surface less than the rotating speed of shaft so that the dynamic stability may be obtained. 4) Sealing at compressor shaft In order for the compressed intake air and lubricating oil not to leak, a seal plate and a seal ring are made to the double structures.
Turbine wheel Outlet Compressor Engine cylinder Exhaust gas outlet Exhaust gas inlet Compressor air supply Turbine Intake air inlet Compressor air passage Exhaust gas passage Exhaust Compressor wheel EFM3003I EFM3002I Maintenance of Major Components - 133 -