An intercooler is a heat exchanger, often used in turbocharged engines, that cools down compressed air before it enters the engine. By cooling the air, intercoolers increase its density, allowing for a more efficient combustion process and ultimately boosting engine power and performance.
Here's a more detailed explanation:Function:Intercoolers reduce the temperature of compressed air produced by a turbocharger or supercharger. How it works:When air is compressed, it heats up. This increase in temperature reduces the air's density, meaning less air can enter the engine. The intercooler removes this heat, increasing the air density and allowing more oxygen to enter the engine for combustion. Benefits:Increased power: More air means more fuel can be burned, leading to increased engine power. Improved fuel efficiency: Efficient combustion leads to better fuel economy. Reduced engine knock: Cooler air reduces the risk of engine knock (premature detonation). Types:Intercoolers can be air-to-air (cooling with ambient air) or air-to-water (cooling with a liquid coolant). Location:Intercoolers are typically located between the turbocharger and the engine's intake manifold.
Intercooling improves the efficiency of a Brayton cycle by lowering the temperature of the compressed air before it enters subsequent stages of compression. This reduces the work input required for compression since cooler air has a higher density and allows more mass flow through the system.
At the same time, coolant is also circulating through the intercooler. Liquid coolant is used to carry excess heat away from the intercooler to an external radiator, which sends “new” cold coolant back to the intercooler to aid in further cooling.
Intercoolers, found in turbo or supercharged engines, provide much-needed cooling that improves the performance and efficiency of the engine. Before describing how they work, we’ll first why you might need one.
For the sake of simplicity, we’ll stick to engines that use turbochargers with internal combustion engines for this explanation. A turbocharger engine produces a lot of heat while compressing ambient air, which allows it to squeeze more air into the engine.
More air means you can burn more fuel and get more power (increasing fuel efficiency and reducing waste). That may sound simple enough, but compressed air gets very hot, which makes it lose density and therefore carry less oxygen.
Oxygen is vital for combustion of the fuel and air mixture. The compressed air needs to be cooled to increase density and oxygen — this is where the intercooler comes in.
Air-to-air intercoolers are the most common application for everyday vehicles due to their simplicity. To describe this system:Ambient temperature air enters the turbocharger intake.This air is converted into hot compressed air.Hot compressed air is transferred to the intercooler, where it is cooled before being sent to the engine.Outside air, passing over the exterior of the intercooler, carries away excess heat.This system usually relies on ambient airflow and additional air ducts from the front of the car to flow through the intercooler and cool the compressed air down, much like a radiator.
An air-to-water intercooler is far more complex, but they are becoming increasingly popular in cars due to higher efficiency. The process works like this:Ambient temperature air enters the turbocharger intake.The turbocharger compresses and heats this air.Heated air is sent to the intercooler, which cools the air down before it is sent to the engineAt the same time, coolant is also circulating through the intercooler.Liquid coolant is used to carry excess heat away from the intercooler to an external radiator, which sends “new” cold coolant back to the intercooler to aid in further cooling.Given there are two circuits carrying air or coolant, this usually requires more components and fittings, such as hoses. Therefore, air-to-water intercoolers can be a little expensive but are still highly effective, particularly in applications where vehicle speed may be slower.
One potential problem includes the risk of heat soak, where there is a build-up of residual heat near the engine and not enough cooling ability to reduce the temperature.
This can generally be solved by increasing the flow of coolant so that it can dissipate heat faster.