* Temperature increases: The compression process is adiabatic, meaning no heat is exchanged with the surroundings. Therefore, the work done on the air by the piston increases its internal energy, causing a significant rise in temperature. This is crucial for the combustion process in a diesel engine.
* Pressure increases: As the volume of the air decreases due to compression, its pressure rises significantly. The pressure increase is directly related to the compression ratio of the engine, which is the ratio of the cylinder volume at the beginning of the compression stroke to the volume at the end of the stroke.
* Density increases: As the air is compressed, its molecules are forced closer together, leading to a higher density.
Important Note: The combination of high temperature and pressure achieved through compression is what allows the fuel to ignite spontaneously in a diesel engine. The injected fuel mixes with the hot, compressed air, and the heat from the air ignites the fuel, creating a controlled explosion that drives the piston down.
