The Role of Intercooler in Turbocharged Engines
Nowadays, many car engines have a prominent "T" symbol, indicating that it is a turbocharged engine. As we all know, a turbocharged engine adds a turbine device to the original engine. During operation, the excess energy generated by the turbine must be reasonably dissipated, which requires a device to "neutralize" it, namely the intercooler. The automatic intercooler increases air resistance, causing the pressure of the turbocharged air to drop, resulting in a reduction in turbocharging effect and engine response slowing down. However, compared with the function of the intercooler to increase engine power, this effect is insignificant.
The automotive intercooler must be used to prevent the turbo lag from becoming severe and the engine response speed slowing down
Generally speaking, the larger the automatic intercooler, the smaller the air flow loss and the higher the cooling efficiency. The longer the air flow stays inside the intercooler, the better the cooling effect. However, the intercooler is like increasing the volume of the intake pipe. The compressed air generated by the turbocharger must first fill this volume before the turbocharging effect can be generated. If used for turbocharging, the direct effect is that the turbo lag becomes severe, even for mechanical superchargers, it will also cause the engine response to slow down. On the other hand, because the turbocharged air must pass through various pipelines, the resistance increases, and the turbocharged pressure will definitely be weakened to some extent. However, this weakening effect only lasts for a short time after stepping on the throttle because the weakened turbocharged air pressure will establish sufficient pressure again in the sealed space between the intercooler and the intake valve, until the pressure relief valve opens. Therefore, the final performance is still the engine response slowing down, and the turbocharging delay phenomenon becomes severe.
The intercooler makes the turbo lag more obvious, but it cannot be removed. Therefore, how to balance cooling efficiency and pressure maintenance is the most difficult problem for engineers. The most fundamental method is to reduce the volume of the entire intake pipeline, reduce the pipeline resistance, and shorten the intake pipeline. Therefore, the automotive intercooler we see is often closely attached to the engine rather than far away from the engine like a radiator. High-boost and large-displacement engines require a large intercooler due to their large intake air volume and high temperature. The larger intercoolers that we are more likely to see are placed on the top of the engine, which can use cold air rushing in to cool it down. This method can be seen in many cars.
Engine cover opening for heat dissipation with the automotive intercooler
One type of layout is to place the auto intercooler below the front of the car. This method fully utilizes the cold wind that comes in front of the car for heat dissipation, but the pipeline is longer and the layout is more complicated. As it is closer to the ground, there is a greater possibility of being damaged by ground debris.
Regarding the cooling method, they are all external air-cooling, suitable for large intercoolers. The current trend is low-boost engines, which do not require large intercoolers. At the same time, in order to make the engine more compact, many engines now use a water-cooling method, which puts a cooler in the intake pipeline, and the air passing through it can be cooled, which is very compact. The auto intercooler is a very important component in the turbocharged engine, which can effectively lower the air temperature and increase the engine power. In addition to reducing the air temperature, we also need to cool the turbocharger and control the boost pressure.