FUEL TREATMENT FUNDAMENTALS (Amtek Research Inc. Canada)
Treatment of Engine Fuels
Here we will address the problems of combustion of Diesel, Marine Diesel, Light Fuel Oil (LDO) and Fuel Oil in compression ignition engines. In compression ignition engines, the metered quantity of fuel is injected into the combustion chamber-near the top dead centre- practically at the end of the compression stroke. During compression, the temperature of the air rises. In the hot air the fuel is injected in small droplets. The fuel droplets while wading through the hot air get ignited. Thereafter, the combustion proceeds further, increasing the pressure of the hot gases. This pressure does the work. There are two types of Diesel Engines: Automotive Engines- in which the speed of the engine depends on the quantity of fuel injected (accelerator controlled) and Power Engines coupled to fixed speed Generators- in which the power generated (pressure) depends upon the quantity of fuel injected each stroke of the engine.
In either case quantity of fuel injected into the combustion chamber is likely to vary-and it does vary. This variation in the fuel burned in each stroke causes the problem of incomplete combustion of fuel –whenever the engine is running at speed or load different from the optimum design value. Incomplete combustion of the fuel is the cause of deposits in the metering system, valve seats, combustion chamber…Results are power loss and increased maintenance and fuel consumption. |
