Cooling system of Internal Combustion Engine: purpose, types and functions
It is known that when an engine is running at high temperatures, this leads to burnout of lubricants. Normal gaps between its parts become violated, resulting in dramatically increased friction and the risk of jamming or breakage. Overheating causes a decrease of the motor cylinders’ filling ratio, which causes detonation of the working mixture in gasoline engines.
Low temperatures are nothing good either. An overcooled motor loses power, because of the increased viscosity of the oil, as well as the growing intensity of the corrosion. So, the cooling system is designed to ensure that the unit works within the most favorable range of temperatures. This reliably protects it from premature wear and from a failure of the main components.
Cooling system: types and functions
Maintaining an optimal temperature level in modern engines is performed by one of the following means:
When working with internal combustion engines fluid-based systems have proven to be the most effective ones. They provide a uniform temperature distribution and smooth running with a low noise level.
Cooling system, in addition to the principal functions, performs the other ones, such as:
- heating the air in the ventilation, air conditioning and heating systems;
- cooling the lubricants;
- lowering the temperature of the exhaust gases;
- lowering the temperature of the air in the turbo-supercharging system;
- cooling the working fluid in the automatic transmission.
The automotive cooling systems all have a number of components in common.
Their design includes:
- radiator with fans;
- oil cooler;
- heat exchanger of the heating system;
- coolant reserve tank;
- centrifugal pump;
- thermostat valve;
- water channels in the block and the head;
- branch pipes;
- control system.
Coolant: key features
Coolant used in cooling systems is a mixture of water, antifreeze and special additives that protect the main components of the engine against corrosion, as well as lubricates the pump. The properties of coolant, which are determined by a set of additives, have a great effect on performance and durability of the basic parts of the heating system and the engine. The most commonly used substance is diluted ethylene glycol.