Coolant

Deutsch: Kühlmittel / Español: Refrigerante / Português: Refrigerante / Français: Liquide de refroidissement / Italiano: Refrigerante /

A coolant is a substance, typically liquid, that is used to reduce or regulate the temperature of a system. An ideal coolant has high thermal capacity, low viscosity, is low-cost, non-toxic, chemically inert and neither causes nor promotes corrosion of the cooling system.

In the aerospace context, coolant refers to a fluid that is used to transfer heat away from a system, such as an engine or electronic component, to keep it within a safe operating temperature range. Coolants can be liquid or gas, and they can be used in a variety of aerospace applications.

Examples of coolant in the aerospace context include:

• Engine coolant: In aerospace, liquid coolants such as water and glycol-based fluids are used to transfer heat away from the hot engine parts of aircraft, such as the combustion chamber, turbine, and exhaust, to keep them within a safe temperature range.

• Electronic coolant: In aerospace, liquid coolants such as water, ethanol, or Freon are used to transfer heat away from electronic components, such as avionics, to keep them within a safe temperature range.

• Cryogenic coolant: In aerospace, liquid or gaseous coolants such as liquid hydrogen and liquid helium are used to transfer heat away from cryogenic systems, such as those used to cool infrared detectors or superconducting magnets.

• Thermal control systems: Aerospace vehicles use thermal control systems which transfer heat away from the vehicle's structure, avionics, and payloads. These systems use coolants such as water, ammonia, or Freon to transfer heat to radiators that release it into space.

Coolant systems are critical to the safe operation of aerospace systems and vehicles, as they help to maintain the temperature of critical components within safe operating limits. The choice of coolant depends on the specific application, and it needs to have the right properties such as thermal conductivity, boiling point and freezing point, and chemical stability, to ensure its proper function.