本文章最後由 peichen 於 2014-6-24 18:03 編輯
依照英文維基百科敘述:Coolant and heat transfer agent
The major use of ethylene glycol is as a medium for convective heat transfer(熱傳遞介質) in, for example, automobiles and liquid cooled computers. Ethylene glycol is also commonly used in chilled water air conditioning systems that place either the chiller or air handlers outside, or systems that must cool below the freezing temperature of water. In geothermal heating/cooling systems, ethylene glycol is the fluid that transports heat through the use of a geothermal heat pump. The ethylene glycol either gains energy from the source (lake, ocean, water well) or dissipates heat to the source, depending if the system is being used for heating or cooling.
Pure ethylene glycol has a specific heat capacity about one half that of water(熱容量只有水的一半). So, while providing freeze protection and an increased boiling point, ethylene glycol lowers the specific heat capacity of water mixtures relative to pure water(乙二醇在提高沸點與抗凍的同時也降低了熱容量). A 50/50 mix by mass has a specific heat capacity of about 3140 J/kg C (0.75 BTU/lb F) three quarters that of pure water, thus requiring increased flow rates in same system comparisons with water.(採取50/50一半混合液只有純水3/4的熱容量,所以要增加冷卻液的流動率來強化冷卻效率) Additionally, the increase in boiling point over pure water inhibits nucleate boiling on heat transfer surfaces thus reducing heat transfer efficiency in some cases, such as gasoline engine cylinder walls. (除此之外,增加沸騰點能避免因熱傳導效率較差使汽油引擎汽缸壁發生核心沸騰-nucleate boiling狀況)Therefore, pure ethylene glycol should not be used as an engine coolant in most cases.(因此純的乙二醇應該不要使用在引擎上)可見100%純度的乙二醇是因為流動率較差而不被使用在引擎上,如果EVANS可以克服流動率,那將是不錯的選擇.
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