Intercooler Effect on Conventional Supercharging Systems

There are three certain problems in automotive applications that cause environmental effect, cost and comfort problems. Therefore, internal combustion engines are required to have not only a high specific power output but also to release less pollutant emissions. For these reasons, current light and medium duty engines are being highly turbocharged because of having negative environmental effects of internal combustion engines. Due to mentioned facts, there are studies going on to improve internal combustion engine performance. Studies for supercharging systems are also included in this range. One of the most important problems faced in supercharging systems is that air density is decreasing while compressing air. Also air with high temperature causes preignition and detonation at spark ignited engines. Various methods have been developed to cool down charge air which is heated during supercharging process. One of these methods is to use a compact heat exchangers called as intercoolers to cool charging air. The purpose of an intercooler is to cool the charge air after it has been heated during turbocharging. As the air is cooled, it becomes denser, and denser air makes for better combustion to produce more power. Additionally, the denser air helps reduce the chances of knock. In this study, the intercooling concept was introduced and performance increase of a vehicle by adding intercooling process to a conventional supercharging system in diesel or petrol engine was analytically studied. Pressure drops, air density and engine revolution were used as input parameters to calculate the variation of engine power output. Also, possible downsizing opportunities of the cylinder volume were presented. It is found that the engine power output can be increased 154by ideal intercooler while single turbocharger without intercooler can only increase 65. Also a meaningful 50downsizing of the cylinder volume possibility achieved by means of turbocharging and intercooling. Finally, future study needs about cycle characteristics of internal combustion engines with intercooling process and intercoolers were discussed.