The standard diesel engine cycle, also known as the Diesel cycle, is a theoretical thermodynamic cycle that represents the operation of a diesel engine. It was first proposed by Rudolf Diesel, the inventor of the diesel engine. The Diesel cycle consists of four distinct processes:
Intake Stroke: The intake valve opens, and fresh air is drawn into the cylinder as the piston moves downward. Unlike in gasoline engines, no fuel is introduced during this stroke.
Compression Stroke: Once the intake valve closes, the piston moves upward, compressing the air within the cylinder. This compression process raises the temperature of the air significantly, typically to temperatures high enough to ignite diesel fuel.
Power Stroke: Near the top of the compression stroke, fuel is injected into the highly compressed, hot air. The fuel instantly ignites due to the high temperature, causing rapid combustion and an increase in pressure within the cylinder. This pressure forces the piston downward, producing power.
Exhaust Stroke: As the piston reaches the bottom of its stroke, the exhaust valve opens, and the piston moves upward again, pushing the burnt gases out of the cylinder.
The Diesel cycle is characterized by constant-pressure heat addition (combustion) and constant-volume heat rejection (exhaust). This cycle is different from the Otto cycle, which is used in gasoline engines, primarily in the method of ignition—diesel engines rely on the heat generated by compression to ignite the fuel, while gasoline engines use spark plugs for ignition. Diesel engines are known for their high efficiency and torque output, making them popular in applications such as heavy-duty trucks, buses, and industrial machinery.
No comments:
Post a Comment