Diesel generators because of its high efficiency, mobility, easy operation in various fields has been widely used. As a prime mover generator sets , which determines the performance efficiency, power generators , such as the size , and the performance of diesel generators and their bodies. Different structural forms of diesel generators have different purposes .

The basic working principle of diesel generators :

Diesel generators are diesel- soft material compression-ignition internal combustion engines. In operation, air is compressed in the cylinder temperature , the timing of diesel fuel injected into the cylinder self- ignition burning tender , high temperature , high pressure gas , the gas pushes the piston acting expansion , thermal energy into mechanical work . Duty cycle diesel generators by the intake , compression, ignition and combustion fuel injection , exhaust expansion work and process components. These processes can be made to achieve a four-stroke diesel generators , but also by two -stroke diesel generators to achieve.

( 1 ) four-stroke diesel engine ( non-pressurized ) basic principle

With a four stroke crankshaft rotation two weeks to complete a job , said the four-stroke cycle diesel engine . The basic structure of a four-stroke engine shown in Figure 2.1 below. Linear reciprocating movement of the working piston as the crankshaft rotates . The instantaneous position of the piston to change the direction of motion of said dead center ( BDC ) , the instantaneous velocity of the piston at TDC is zero . Only point farthest from the center of the crankshaft , said the dead , the dead , said the recent bottom dead center .

Crank pin center distance between the center of the spindle neck , said crank radius R. Connecting rod big distance between the centers of the small end of said connecting rod length L.

The distance between the bottom dead center , said piston stroke ( stroke ) S.

Piston stroke equal to twice the crank radius , i.e., S = 2R.

The piston , the movement between the lower dead point of the cylinder swept volume of said working volume Vs.

( 2 ) two -stroke diesel engine basic working principle

With two stroke crankshaft rotation one week to complete a job , said two-stroke cycle diesel engine .

Two-stroke and four-stroke engine type , which is provided on the cylinder intake port , an exhaust port on the cylinder , the left air intake port . Exhaust port slightly higher than the intake port , the intake port opening and closing by the control piston . In addition, two -stroke diesel engine with a scavenging

Pump. Scavenging pump previously given away and scavenging air compression chamber , the scavenging air pressure tank ( scavenging pressure ) slightly higher than the atmospheric pressure .

(3) The basic working principle of diesel pile pressure

Increase the intake pressure of the diesel engine , the intake can increase the density , so as to achieve the same charge into the cylinder volume is the amount of additional air for injecting more fuel , to make more useful work. This in order to improve the inlet pressure to increase engine power method called " booster ."

Fresh air compressor to compress its energy directly from the use of the main engine crankshaft through gears and other mechanical drive way , this way , said supercharger supercharged ; energy of the exhaust gas discharged cylinder diesel engine is also useful in disaster turbine expansion work ,

By the turbine to drive the way , said exhaust gas turbocharger .

Turbocharged four-stroke diesel engine work diagram . From the exhaust gas turbocharger turbine 8 and its coaxial centrifugal compressor 2 and so on. Cylinder diesel engine exhaust gas through the exhaust pipe into the turbine 6 8 , in which the rotation of the turbine expansion work to promote and drive the compressor 2 work . Fresh air is compressed through the inlet pipe 3, to the respective cylinders of the diesel engine .

Currently, almost all marine diesel engine using exhaust gas turbocharger .