Why is fuel temperature critical for engine operation?

Fuel temperature is critical for engine operation primarily because it influences fuel viscosity and efficiency. Viscosity refers to a fluid's resistance to flow; as temperature changes, the viscosity of the fuel also changes. Warmer fuel tends to be less viscous, allowing it to flow more easily through the fuel system. This is significant because the fuel must be atomized effectively in the combustion process for optimal engine performance and efficiency. If the fuel is too viscous, it may not atomize properly, leading to incomplete combustion, reduced engine performance, and increased emissions.

Additionally, higher temperatures can affect the efficiency of combustion by ensuring that the fuel vaporizes correctly before entering the combustion chamber. If the fuel is too cold, it may not vaporize adequately, which can cause starting issues, rough operation, or incomplete combustion, adversely affecting overall efficiency and performance.

While temperature does affect other factors, such as density and storage life of fuel, the direct impact on viscosity and combustion efficiency is crucial for engine operation.