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An intercooler is any mechanical device used to cool a fluid, including liquids or gases, between stages of a multi-stage heating process, typically a heat exchanger that removes waste heat in a gas compressor.〔 They are used in many applications, including air compressors, air conditioners, refrigerators, and gas turbines, and are widely known in automotive use as an air-to-air or air-to-liquid cooler for forced induction (turbocharged or supercharged) internal combustion engines to improve their volumetric efficiency by increasing intake air charge density through nearly isobaric (constant pressure) cooling. ==Internal combustion engines== Intercoolers increase the efficiency of the induction system by reducing induction air heat created by the supercharger or turbocharger and promoting more thorough combustion. This removes the heat of compression (i.e., the temperature rise) that occurs in any gas when its pressure is raised or its unit mass per unit volume (density) is increased. A decrease in intake air charge temperature sustains use of a more dense intake charge into the engine, as a result of forced induction. The lowering of the intake charge air temperature also eliminates the danger of pre-detonation (knock) of the fuel/air charge prior to timed spark ignition. This preserves the benefits of more fuel/air burn per engine cycle, increasing the output of the engine. Intercoolers also eliminate the need for using the wasteful method of lowering intake charge temperature by the injection of excess fuel into the cylinders' air induction chambers, to cool the intake air charge, prior to its flowing into the cylinders. This wasteful practice (before intercoolers were used) nearly eliminated the gain in engine efficiency from forced induction, but was necessitated by the greater need to prevent at all costs the engine damage that pre-detonation engine knocking causes. The ''inter'' prefix in the device name originates from historic compressor designs. In the past, aircraft engines were built with charge air coolers that were installed between multiple stages of forced induction, thus the designation of ''inter''. Modern automobile designs are technically designated aftercoolers because of their placement at the end of the supercharging chain. This term is now considered archaic in modern automobile terminology, since most forced-induction vehicles have single-stage superchargers or turbochargers, although "aftercooler" is still in common use in the piston-engined aircraft industry. In a vehicle fitted with two-stage turbocharging, it is possible to have both an intercooler (between the two turbocharger units) and an aftercooler (between the second-stage turbo and the engine). The JCB Dieselmax land speed record-holding car is an example of such a system. In general, an intercooler or aftercooler is said to be a charge-air cooler. Intercoolers can vary dramatically in size, shape and design, depending on the performance and space requirements of the entire supercharger system. Common spatial designs are front mounted intercoolers (FMIC), top mounted intercoolers (TMIC) and hybrid mount intercoolers (HMIC). Each type can be cooled with an air-to-air system, air-to-liquid system, or a combination of both. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「intercooler」の詳細全文を読む スポンサード リンク
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