- Apr 4th. 2014
- By CourtenaySport
Water is an excellent fluid for cooling whilst in a liquid state, but when water turns to steam it has virtually no capacity for heat transfer. Evans is a superior fluid for transferring heat in engines because it remains in a liquid state until above 180°C. This article details the benefits of a significantly higher boiling point.
Within an engine cooling system the hottest surfaces are those adjacent to the combustion chamber, specifically the cylinder liners and cylinder head. In these hot spots water is likely to vaporise preventing efficient cooling and causing loss of performance and unnecessary engine damage. When the coolant fails in this way the engine becomes even hotter causing more hot spots and more steam.
Evans waterless coolants will not boil around these engine hotspots maintaining efficient cooling performance even when the engine is put under extreme conditions. When water turns to steam it pressurises the cooling system putting strain on hoses and other components. The significantly higher boiling point of Evans coolants means 75% less pressure than water resulting in a less stressed cooling system.
Water contains oxygen which causes corrosion and also allows electrolytic activity which further damages engine metals (chemical limitations of water). Evans waterless coolants eliminate corrosion and electrolytic activity significantly increasing the life of the engine.
Traditional water based coolants regularly cross the thermal boundary that separates efficient Nucleate Boiling (A) from inefficient Critical Heat Flux (CHF). CHF is synonymous with the condition ‘Departure from Nucleate Boiling’ (DNB). When DNB occurs, a layer of steam bubbles form adjacent to the engine hot spots (B).
Steam dissipates less than 1/30th of the heat that water does, rapidly over-heating local metal, causing premature detonation. The high boiling point of Evans Waterless Coolants, such as Power Cool 180, prevents DNB providing more efficient cooling in engine hot spots.