For many car fans, the intercooler inside the front protector is a dream modification part and an indispensable performance symbol, just like the sound of the pressure relief valve. However, what is the knowledge of all kinds of intercoolers that look the same? What do you need to pay attention to if you want to upgrade or install? Each of these questions will be answered in this unit.
The installation purpose of the intercooler is mainly to reduce the intake temperature. Some people may ask: why do you need to reduce the intake temperature? This brings us to the principle of turbocharging. The working principle of turbocharging is simply to use the exhaust gas of the engine to impact the exhaust blade, and then drive the intake blade on the other side to force compressed air and send it to the combustion chamber. Because the temperature of the exhaust gas is usually as high as 8 or 9 Baidu, the turbine body is also in an extremely high temperature state, so the temperature of the air flowing through the intake turbine end will be increased. In addition, the compressed air will also produce heat (because the compressed air molecules become smaller, they will squeeze and friction each other to produce heat energy). If this high temperature gas enters the cylinder without cooling, it is easy to lead to too high combustion temperature of the engine, and then it will make the gasoline precombustion detonation, so that the engine temperature rises even more. At the same time, the volume of compressed air will greatly reduce the oxygen content due to thermal expansion, which will reduce the benefit of pressurization and naturally fail to produce the power output. In addition, high temperature is also the invisible killer of the engine, if we do not try to reduce the operating temperature, once the weather is hot, or in the case of driving for a long time, it is easy to increase the probability of engine failure, so it is necessary to install an intercooler to reduce the intake temperature. After knowing the function of the intercooler, then we will discuss its structure and the principle of heat dissipation.
The intercooler is mainly composed of two parts. The first part is named Tube, its function is to provide a channel to accommodate compressed air to flow through, so the Tube must be a closed space, so that the compressed air will not leak pressure, and the shape of the Tube is also divided into square, oval and long cone, the difference lies in the choice between wind resistance and cooling efficiency. The second part is called Fin, which is commonly known as the fin, usually located between the upper and lower layers of Tube, and closely bonded with the Tube. Its function is to dissipate heat, because when the compressed hot air flows through the Tube, the heat will be transmitted to the fin through the outer wall of the Tube. At this time, if the air with low outside temperature flows through the fin, It can take the heat away and cool the air inlet temperature. Through the above two parts continue to overlap together, until 10 ~ 20 layers of the structure, is called the Core, this part is the so-called intercooler main body. In addition, in order to make the compressed gas from the turbine have buffer and pressure storage space before entering the Core, and to improve the air flow rate after leaving the Core, a part named Tank is usually installed on both sides of the Core. Its appearance is like a funnel, and a circular inlet and outlet are also set on it to facilitate the connection of the silicone tube. The intercooler is composed of the above four parts. As for the principle of heat dissipation of the intercooler, as just mentioned, it is to use many transverse pipes to split the compressed air, and then the outside straight cold air from the front, and then through the heat dissipation fin connected with the Tube, the purpose of cooling the compressed air can be achieved, so that the intake temperature is closer to the outside temperature, so that to increase the heat dissipation efficiency of the intercooler, This purpose can be achieved by increasing the area and thickness of the Tube to increase the number, length and heat dissipation fins. But is it that easy? In fact, it is not, because the longer and larger the area of the intercooler, the more likely to produce the problem of intake pressure loss, and this is one of the main problems discussed in this unit. Why does pressure loss occur
An intercooler that emphasizes performance, in addition to having good heat dissipation capacity, the reduction of pressure loss must also be taken into account. However, the reduction of pressure loss and the improvement of cooling efficiency are completely opposite in technique. For example, if an intercooler with the same volume is designed entirely from the point of view of heat dissipation, the Tube inside needs to be made finer and the number of fins should be increased. This increases air resistance; However, if we start to maintain the pressure level, and have to increase the thickness of the Tube and reduce the fin, the efficiency of heat exchange is poor, so the modification of the intercooler is not as simple as we imagine. Therefore, most of the methods to balance cooling efficiency and pressure maintenance will start from the Tube and fin
The fins of general intercooler are usually straight strips without any openings, and as long as the width of the intercooler is, the fins are as long as they are. However, since the fins play the main role of heat dissipation function in the whole intercooler, as long as the area in contact with cold air is increased, the heat exchange power can be improved. Therefore, the fins of many intercooler, Various forms of design, among which the wavy or commonly known as the louver design of the fin is the most popular. However, in terms of heat dissipation efficiency, the overlapping fins are the best, but the wind resistance is also the most obvious, so it is more common in the Japanese D1 racing car, because the speed of these racing vehicles is not fast, but it needs good heat dissipation effect to protect the engine swimming at high speed. Refit the intercooler.
