How does supercharger work in a car

The screws compress air when they rotate. A centrifugal supercharger looks kind of like a snail shell, with an impeller wheel that compresses the air. Although all of these designs provide a boost, they differ considerably in their efficiency. Each type of supercharger is available in different sizes, depending on whether you just want to give your car a boost or compete in a race. The Roots supercharger is the oldest design.

Philander and Francis Roots patented the design in as a machine that would help ventilate mine shafts. In , Gottleib Daimler included a Roots supercharger in a car engine. As the meshing rotors spin, air trapped in the pockets between the lobes on the rotors is carried between the fill side and the discharge side.

Large quantities of air move into the intake manifold and "stack up" to create positive pressure. For this reason, Roots superchargers are really nothing more than air blowers, and the term "blower" is still often used to describe all superchargers.

Roots superchargers are usually large and sit on top of the engine. They are popular in muscle cars and hot rods because they stick out of the hood of the car.

However, they are the least efficient supercharger for two reasons: They add more weight to the vehicle and they move air in discrete bursts instead of in a smooth and continuous flow.

A twin-screw supercharger operates by pulling air through a pair of meshing rotors that twist alongside each other. Like the Roots supercharger, the air inside a twin-screw supercharger is trapped in pockets created by the rotor lobes. But a twin-screw supercharger compresses the air inside the rotor housing. That's because the rotors have a conical taper, which means the air pockets decrease in size as air moves from the fill side to the discharge side.

As the air pockets shrink, the air is squeezed into a smaller space. This makes twin-screw superchargers more efficient, but they cost more because the screw-type rotors require more precision in the manufacturing process.

Some types of twin-screw superchargers sit above the engine like the Roots supercharger. They also make a lot of noise. The compressed air exiting the discharge outlet creates a whine or whistle that must be subdued with noise suppression techniques.

A centrifugal supercharger powers an impeller — a device similar to a rotor — at very high speeds to quickly draw air into a small compressor housing. Impeller speeds can reach 50, to 60, RPM. As the air is drawn in at the hub of the impeller, centrifugal force causes the air to radiate outward.

That means the air leaves the impeller at high speed but low pressure. A diffuser — a set of stationary vanes that surround the impeller — converts the high-speed, low-pressure air to low-speed, high-pressure air. Air molecules slow down when they hit the vanes, which reduces the velocity of the airflow and increases pressure.

Centrifugal superchargers are the most efficient and the most common of all forced induction systems. They are small, lightweight and attach to the front of the engine instead of the top. They also make a distinctive whine as the engine revs up — a quality that may turn heads out on the street.

Any of these superchargers can be added to a vehicle as an after-market enhancement. Several companies offer kits that come with all of the parts necessary to install a supercharger as a do-it-yourself project. In the world of funny cars and fuel racers, such customization is an integral part of the sport. Several auto manufacturers also include superchargers in their production models.

The biggest advantage of having a supercharger is the increased horsepower. Attach a supercharger to an otherwise normal car or truck, and it will behave like a vehicle with a larger, more powerful engine. But what if someone is trying to decide between a supercharger and a turbocharger?

This question is hotly debated by auto engineers and car enthusiasts, but in general, superchargers offer a few advantages over turbochargers. Superchargers do not suffer lag — a term used to describe how much time passes between the driver depressing the gas pedal and the engine's response. Turbochargers suffer from lag because it takes a few moments before the exhaust gases reach a velocity sufficient to drive the turbine.

Superchargers have no lag time because they are driven directly by the crankshaft. Roots and twin-screw superchargers, for example, provide more power at lower RPM. Shift also offers free vehicle history reports, so you know your car is good to go from the get-go. A supercharged engine has several benefits when compared to a naturally aspirated version. Increased horsepower and torque are the most obvious. Extra oomph off the line is a nice feature to have whether you're driving through the city or traveling through the countryside.

In the case of a centrifugal supercharger, you're getting a smaller engine to produce power similar to a larger one while still achieving good fuel economy. A centrifugal supercharger's clean design and placement mean your car has the same flat hood and open engine bay as any other.

Then there's the sound. You have to hear it to understand it. The same way a high-performance engine sings all the right notes, a supercharger spinning at 50, rpm lets out a noise that's racy and innovative all at once. If you're used-car shopping, why not try Shift and get a fully inspected vehicle at a fair, no-haggle price?

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Cars How Does a Supercharger Work? Read time. Sell or trade-in Find out your car's value in minutes. No items found. What is a supercharger? The supercharger increases air intake simply by compressing air at above atmospheric pressure before pumping into the combustion chamber. With more air intake, more fuel can be pumped into the combustion chamber for the engine to combust to create more energy.

After the air is compressed by the supercharger, it gets hotter and thus becomes less dense. Therefore, for the supercharger to create the optimal air so that the engine can generate the most power, the compressed air exiting the supercharger must be cooled down before it enters the engine via the intake manifold.

This belt in turn is wrapped around the pulley. Power is drawn from the crankshaft via the accessory belt to rotate the pulley. This makes the drive gear, which is connected to the pulley, rotate. The drive gear, in turn, rotates the compressor gear. The compressed, dense air is then released into the intake manifold of the engine.

There are two types of intercoolers: air-to-air and air-to-water. Cooler air or water is run through a system of tubes. The heated compressed air will cool down after being in contact with these cooler tubes. Depending on how much power boost you want to give your car, you can choose among different sizes of each type of superchargers. The Roots supercharger is the oldest design, which was dated back to and named after its inventors, Philander and Francis Roots.

Roots superchargers are technically air blowers. Air flows into the supercharger and is trapped in a system of meshing lobes. D ue to this design of meshing lobes, a Roots supercharger is big and heavy, and will stick out of the hood of a car. This design also makes it the least efficient, as the process cannot create a continuous flow of compressed and dense air into the engine.

Basically, a supercharger is an air compressor. Its purpose is to increase the pressure or density of air supplied to an internal combustion engine much like a turbocharger. With more air, the engine can also add more fuel, thus doing more work and producing more power. The supercharger itself can be powered and give power by means of either a belt, shaft, or chain connected to the crankshaft of the engine. The downside is that superchargers sap power from the engine before they produce any themselves.

Although there are various types of superchargers, the purpose of each is the same: to increase air pressure as it enters the engine. This is especially useful in aviation, where air at high altitudes is particularly thin, but any engine can unlock more performance if it gets more air pressure with more oxygen and more fuel.

Much like a turbo, increasing density is the goal. However, while turbochargers scavenge exhaust gasses that would otherwise be wasted, a supercharger tends to sap power from the engine before it produces any, as it is connected to the crankshaft and cannot be started without it.

Once the supercharger has started spinning, it pumps denser air into the engine, which starts producing more power with more air and fuel, but until then, the blower is actually drawing power. The upside is that it takes very little time for the supercharger to speed up, so throttle response remains excellent and the power feels like it is always available.

However, superchargers can cause a spike in temperature, and if these temperatures get too high, detonation can occur. Fortunately, you can fit an intercooler as you would with a turbo, thus reducing intake temps and increasing density. Before we go into this any further, we have to stop with the generalizations and consider the different types of superchargers out there.

With turbochargers, there are also various types, but they all work in relatively similar ways; you can read up on everything turbocharger-related here. With superchargers, the different types have more diverse methods of doing their job a screw supercharger is very different from a centrifugal supercharger , but the end goal remains the increase of air pressure as it enters the intake of the engine. Two main types of superchargers will be considered although less common variants exist as well but we will list some of the subcategories too.

If you're reading this, you probably have an interest in supercharged engines and already know some of the models out there, whether that's your favorite muscle car or one of the more high-end supercars. Here we'll list some commonly known supercharged cars and sports cars , as well as some unusual cars from the past and the present that have used superchargers.

There's much to be said for superchargers and the advantages they bring to the performance of your car, although lowering fuel economy and upping the MSRP are some negatives to consider, too. Still, some of the best high-performance vehicles out there are supercharged. We also elaborate on the differences between turbocharging and supercharging in our blog post, here.