How a turbo charger works

22.03.2019
How a turbo charger works

How a turbo charger works ➤ A way to improve engine performance ➤ The extra power in a turbo car ☝

What come in your mind when you hear those heavy engines rumbling around? For many, those are engines for sports cars. But do you know why the engines are so loud and powerful? Well, that is what we are here to find out.

When you talk about high performance engines, especially for race cars, the topic of turbochargers usually pops up. This is because turbochargers are in every sense associated with these engines. It is all about how powerful the engines are and how fast they car can go.

Turbochargers are also associated with diesel engines of larger vehicles. So it is not only on race cars that you will get a turbo charger. It can offer a great boost to the engine’s horse power without increasing the weight of the car. This is a big plus that makes the turbo chargers very famous.

In this guide, we are going to learn everything about these important components for motor vehicles. We want to see how they increases the power output of an engine under extreme operating conditions yet remains functional. We want to see how different components like wastegates, ceramic, turbines blades and ball bearings assist a turbo charger perform well.

A way to improve engine performance

The truth, there is nothing you can call a perfect invention. Everything that has been made by human hands can be improved upon. You can make it cheaper, more efficient and friendlier to the environment. A good example is the internal combustion engine. One may think it is so good to have a machine powered by an engine that can take them at a higher speed on ground than they would in the air.  However, a slight improvement on these could bring out engines that are faster, can go further and consumes less fuel.

One of the very effective ways to improve an engine in this manner is to use a turbo charger. Turbo charging involves a pair of fans that harness the power from the exhaust waste from the rear of the engine. It then utilizes this power to produce more power for the engine. This is where the “oomph” of such cars as racing auto comes from.

Everyone must have heard about turbo chargers and how they boost the car. But many don’t understand how exactly they work. Continue reading.

What is a turbocharger?

This is probably the first question you will be asking if anyone talks to you about this component. It is clear that people always want to know everything about what they have a round them. And turbo charging is one topic that always comes up when someone is looking for a high power vehicle.

Think of the time to watch cars buzz past you with sooty fumes from their tail exhaust pipes. If they are many, you would think they were many huge bees passing by.

One thing that is apparent is that exhaust fumes cause air pollution. Aside from that, they waste a lot of energy. The exhaust is simply a mixture of hot gases pumping out of the vehicle at a high speed. These fumes contain heat and motion energy; they disappear into the air just like that.

How wonderful would it be if the engine were to instead, convert these energy into something more useful. This would make the car go faster while ensuring a cleaner environment. That is exactly the duty that a turbo charger plays.

How does a normal car engine produce power? It does so by burning fuel in cylinders (sturdy metal cans). One thing very important to note is that, air is very important in the combustion engines. It means a lot to the amount of power your car can produce and how fast they can go.

When you step on the accelerator, it is not more fuel you are letting out, it is more air you are letting in. This air goes and mixes with the fuel to produce high-combustion fumes. These are the fumes that are burned to produce the power that moves the vehicle forward.

The air enters each cylinder where it will find the fuel. It then burns a small explosion that pushes the piston out. The piston turns the shaft and the gears, making the car wheels to turn.  The piston has springs that pull it back into position. Upon return, it finds the combust fumes in its place and pushed them out as exhaust.

The more fuel-air mixture a car can burn, the faster is moves. This means, a car that has more and bigger cylinders can burn more fuel and in essence move faster. The speed of burning also counts. Theoretically, an engine should burn as much fuel as possible in one second.

You can make your car go faster by adding more cylinders to the engine. If you get a chance to see through the engines of super-fast cars, you will notice they have eight to twelve cylinders. Normal cars have only four to six.

But if you think adding a more cylinders is not an option, a better way is to use a turbo charger. This component forces more air into the cylinders every second, ensuring the vehicle gets maximum air intake. The more air the mixes with the fuel, the more powerful your engine becomes.

To achieve this boost, the turbocharger utilizes the exhaust flow from the engine to spin a turbine. This turbine pumps more air into the combustion chamber. The turbines in these components spin at speeds of about 150 rotations every minute. This gives them 30 times more rotations than normal cars. The temperatures are also very high because the turbines are hooked to the exhaust.

The best part about a turbo charger is that, it is simple, cheap and an extra accessory that can get more power from the same engine. They do not add any extra weight to the car. And that is one of the advantages that make many people love them.

For those who love extra speed and more power, you can use these components to make your dreams come true.

The location of the Turbo charger

A turbocharger, as seen above allows an engine to burn more fuel and air. It sends more air into the cylinders, making the car move faster and stronger.

One of the things that may cause inefficiency is that the power to spin the turbines does not come free.  These turbines restrict the flow of exhaust fumes. The engine is forced to push against a higher back-pressure on the exhaust stroke. There is a little bit of power subtracted from the cylinders that are firing back. This is why there is more noise from a car that is fitted with turbo charging parts.

How does a turbo charger work?

If you have any knowledge on the working of a jet engine, then you can easily understand what happens with your car’s turbo chargers. You already know the basics and getting the rest is not hard. But for those who have no clue yet, a jet engine works by sucking in cold air at the front and squeezing it into the chamber where fuel is burned. Hot air is them forced out from the back.

The exiting hot air roars as it passes the turbine (they look like a windmill).  This dried the compressor in-front of the engine. During this process, air is pushed into the engine, making the fuel to burn properly hence, producing enough power to lift and move the aircraft.  A turbocharger working applies the same principle to the car’s piston engine. The exhaust gas and power is used to drive a turbine, which in turn forces more air into the combustion cylinders. The air compressor is used to push this air and keep it inside.

By performing like this, it makes a turbocharged car move faster by the spinning of the crank-shaft. This is a disadvantage because another important turbo charger function is to save energy. A super charger on the other hand tends to steal some energy from the car. It is generally not very helpful.

As you can see from the explanation above, air intake is the key factor in how a turbo chargers works. It ensures energy (kinetic and heat), from the engine don’t go to waste. Instead, it is utilized to offer more power to the vehicle. This makes the turbocharger both and environmentally and car friendly component. Even though the engine will produce about more noise than normal, it does not compare to the benefits you get.

How is the working of turbo charger in practice? As seen above, the turbocharger working principle is similar to that of a jet engine. A turbocharger can be described simply as two little air fans. They sit on the same metal shaft and spin together. There is not so much about them if you consider how small they are. One of the fans – the turbine- is situated in the exhaust stream from the cylinder.

As the hot air from the cylinders is blown past the blades on this fan, it forces them to rotate. They are connected to a shaft (which becomes the center hub rotating assembly) which rotates together with it.

There is the second fan which is known as the compressor. It sits on the same shaft as the turbine, making it to spin too. This fan is located in the car’s intake. This makes it to draw in air into the car and forces it into the cylinders. In essence, this is the part of the turbo charger that handles air intake. The faster it spins, the more air is drawn into the engine.

Note however, that compressed gas causes the molecules to brush against each other, which in turn produces hit. Consider using a bicycle pump for instance, it warms up when you are inflating the tire because of the heat in the compressed air. That is a problem in the turbocharger, isn’t it?

Warm air is less dense, which explains why such air rises above the radiator. It is also less effective in helping the fuel to burn out.

This means it would be much better if the air from the compressor was cooled. It needs to be cooled before entering the cylinders. There is a solution for that in the turbocharger. The air passes over the heat exchanger that removes the extra heat and sends it to a different direction. This way, the air coming into the cylinder is denser and more combustible.

Summary of how turbo charger works

The simplest way to explain this even without turbocharger diagram that the exhaust drives the turbine connected to and powers the compressor. This process rams air into the engine. You can always feel the air from the ramming of the turbo engine.  Here is a summary of the whole process.

  • In the initial step, cool air enters the engine’s intake. It is directed towards the compressor ( the blue fans) on the turbo charger.
  • The compressor is rotating already and helps the engine to suck in air. This is a very important step that determines how much power the engine will produce.
  • The compressor performs another function on the air. It heats up the incoming air and forces it our again.
  • The hot compressed air not needs to be cooled. It therefore passes over the heat exchanger for the heat to be removed. It is cooled so that it can be more effective.
  • The cooled yet still compressed air passes into the cylinders. This air has extra oxygen which is essential in helping the engine burn more fuel.
  •  The cylinder now is able to produce more energy since they burn more fuel. The energy converts into more power and is sent to the wheels through the piston, shaft and gears.
  • There is still waste gas from the cylinders. It is forced to exit through the exhaust outlet.
  • These gasses are hot and moving at a high speed, forcing the turbine fan to rotate at a high speed. This is where it all begins from.
  • Since the spinning turbine is mounted on the same shaft as the compressor, the compressor is forced to rotate with it. The compressor continues to spin sending the hot air into the cylinder once again.
  • The exhaust gas leaves the car. In essence, the energy in the exhaust fumes is taken out, leaving only empty fumes to leave the engine.

Practically, a turbocharged engine is defined by the turbine taking in exhaust fumes through the intake. This air drives the compressor which takes in clean air from the outside and pumps it to the engine. There are some designs that feature an electric cooling system.

 

The extra power in a turbo car

You might be wondering where the extra power comes from. Whereas the turbocharger gives more power, the extra power does not come directly as a result of exhaust gas. This sounds confusing, right?  We use the turbine in the turbocharger only to harness some energy from the exhaust to help rotate the compressor. In turn, the engine burns more fuel each second.

It is from this extra fuel that more power erupts. The exhaust gas is not giving any power, but only powering the right component.  The turbocharger is not connected directly to the crankshaft, or the wheels of the car. Therefore it does not directly contribute to the car’s driving power in any way. All it does is helping the engine burn more fuel.

A bigger and better turbocharger will hive the engine more power. Theoretically, constant improvements on the turbo charger can make your engine even more powerful. But there is a limit to the amount of energy you can use to drive your turbo charger. This is because you can never force too much air in or out of the engine.

Advantages and disadvantages of a turbocharger

A turbocharger can be used on both gas and diesel engines. It can go on any vehicle, including trucks and buses. One of the basic advantages is more power to the engine.

This is also a disadvantage since more power means you will need more energy input. A turbocharged car is therefore not as efficient on energy as the one that does not have.

Another advantage is that cars fitted with turbochargers have much smaller engines. They can use for instance a turbocharged V6 instead of V8. Or use a four cylinder with a turbocharger instead of a 6 cylinder engine. This is where fuel saving comes in. You can get up to 10% fuel save.