Fuel Systems

Abstract

The fuel supply system is usually an integral part of a prime mover. For medium and large industrial prime movers, however, it may be necessary to install fuel storage tanks remotely, arrange pipe-work from tank to prime mover and select suitable filters. Fuel systems for the power units now to be described have to satisfy various requirements. In the gasoline engine, for example, the fuel is mixed with the air in the carburettor, drawn into the cylinder, compressed and spark-ignited. In the diesel engine, only air is drawn into the cylinder and compressed: the fuel is then injected directly into the combustion chamber as a fine spray, and combustion commences spontaneously during injection as a result of the heat generated during compression. In the gas turbine engine, fuel is pumped continuously through an atomiser into a combustion chamber where there is an excess of air moving at high velocity. Electrical ignition is necessary only during initial start up. Because of these fundamental differences, it is necessary to discuss separately the systems for different types of prime mover.