Engine cooling is a process that helps an engine maintain a steady temperature and avoid overheating. This ensures that the engine operates at maximum efficiency and prevents damage to the engine and its components. There are a number of methods that can be used to cool engines large and small, and the cooling system is an integral part of the components that make the engine function.
Engines use chemical reactions to generate heat and mechanical energy. The internal combustion engine is a commonly used example of an engine; it works by using controlled explosions to push pistons that make the engine move, converting it into mechanical energy that can be used to put a vehicle in motion. This process is far from efficient, however. A great deal of heat is created during the process, and it can quickly rise to dangerous levels.
When engines are designed, their developers design them to run at an optimal temperature. An engine cooling system allows an engine to heat up fast to reach this optimal point, and then forces the engine to hold that temperature. Engines that run too cold or too hot will wear out quickly. Catastrophic failure of some engine components can even result in permanent damage to the entire engine.
Air cooling systems for engines were once very popular. Such systems draw air over or through the engine to move the waste heat out and vent it away. Today, liquid cooling is more common. With liquid cooling, water and other fluids are circulated to absorb the heat of the engine and keep the temperature down. The fluid mix varies depending on the operating temperature of the engine and the conditions that can arise while the engine is running.
The engine cooling system includes fans to move hot air, along with hoses for air and fluids used to wick away waste heat. People may have noticed that even with cooling, engines run very hot, and it can be dangerous to touch an engine that has just been running. Usually engines are mantled to shield the rest of the engine compartment from the heat.
When an engine cooling system fails, the engine can overheat. Some engines automatically shut off when they get too hot or signal the operator as a warning. The engine must be allowed to fully cool before it can be run again, and if it continues to overheat, it may require servicing to find out why the engine cooling system is not working correctly.