The Power of Turbochargers: Boosting Performance and Efficiency

Introduction

In the world of internal combustion engines, turbochargers have become a popular method of increasing power and efficiency. 

This gas compressor, often referred to simply as a turbo, is a form of forced induction that forces air into the engine, resulting in more power for a given displacement. 

In this blog, we will explore the inner workings of turbochargers and their impact on engine performance.

The Components of a Turbocharger

At its most basic level, a turbocharger consists of three major components: the turbine, the compressor, and the bearing system that supports the turbine shaft connecting the turbine and compressor wheels. 

The turbine is located on the hot side of the turbocharger and is bolted onto the engine's exhaust manifold. 

As the engine runs, the exhaust gases pass through the turbine, spinning a fan called the turbine wheel. This spinning motion converts heat and pressure into rotational force, which in turn spins the compressor wheel. 

The compressor's job is to suck air into the turbocharger, pressurize it, and force it into the engine's intake manifold.

This compression of air helps turbocharged engines make more power. By providing a boost in air pressure, turbochargers can deliver significantly more air into the engine compared to normal atmospheric pressure. 

This boost is typically measured in pounds per square inch (psi) and can range from six to eight psi in a typical turbocharged engine. 

With 14.7 psi being the normal atmospheric pressure at sea level, turbochargers can provide around 50% more air into the engine, resulting in a corresponding increase in power.

Benefits of Turbocharging

For decades, turbochargers were prized for their ability to boost horsepower, making them popular in race cars and high-performance sports cars. 

However, modern turbochargers have evolved to offer benefits beyond pure horsepower. They can also increase fuel economy and make smaller engines more efficient and capable of achieving highway speeds.

In addition to the turbine and compressor, a turbocharger also includes other components like the wastegate, intercooler, bearing system, and oil supply. 

The wastegate is a valve that controls the amount of exhaust gases flowing through the turbine, regulating the boost pressure and preventing the turbocharger from over-speeding. 

The intercooler cools the compressed air before it enters the engine, increasing the density of the air and resulting in more oxygen available for combustion. 

The bearing system supports the shaft and allows it to rotate smoothly, while the oil supply system provides lubrication and cooling to the turbocharger's bearings and shaft.

A Brief History of Turbochargers

Before the invention of the turbocharger, forced induction technology was the only possible thing using mechanically powered superchargers. 

The use of superchargers began in 1878 with the development of supercharged two-stroke gas engines. However, it was not until 1905 that the first turbochargers began to take shape.

Swiss engineer Alfred Büchi introduced a prototype turbocharger in 1905 to increase the power of a diesel engine. 

It took Büchi 20 years to successfully apply the exhaust gas turbocharging system to a diesel engine, achieving a power increase of over 40%. These turbochargers at  early were referred  as a "turbo superchargers" at the time, as all forced induction devices were classified as superchargers.

Turbocharging gained prominence during World War I when engineers sought ways to improve the performance of airplanes at higher altitudes. 

Turbochargers proved effective in countering the power loss caused by reduced air pressure and density at high altitudes. By the mid-1920s, turbocharged diesel engines also started appearing in ships and locomotives.

During World War II, turbochargers were extensively used on military aircraft to maintain power at high altitudes, making them faster and more efficient. 

Turbochargers also found their way into commercial applications, with Boeing's B-17 Flying Fortress and other aircraft utilizing turbochargers produced by General Electric.

The first automotive use of a turbocharger came in 1978 when Swiss manufacturer SAR introduced a turbocharged diesel truck engine. 

However, it wasn't until 1962 that turbochargers made their way into mass production cars with the introduction of the Oldsmobile Jetfire and the Chevrolet Corvair Monza Spider. 

These cars ushered in a new era of turbocharged engines, offering increased power and efficiency.

Since then, turbocharging technology has continued to evolve. Twin-turbocharged engines, which use two turbochargers working in tandem, became popular in larger engines, reducing turbo lag and providing improved performance. 

Variable geometry turbochargers and twin-scroll turbochargers were introduced to further reduce turbo lag and enhance efficiency.

The Future of Turbocharging

The demand for emissions reduction and electrification is paving the way for new turbocharger technologies. 

Electric turbochargers are emerging as the future of turbocharging, offering a new solution for smaller engines without sacrificing power delivery or efficiency. 

There are currently two types of electric boosting systems: electrically assisted turbocharging and turbochargers with electric compressors.

Electrically assisted turbocharging utilizes an electric motor to drive the turbocharger shaft and can also function as a generator, creating electricity by connecting the electric motor to the compressor wheel. This setup eliminates turbo lag and improves drivability and performance.

The history of the turbocharger is far from over. As the automotive industry continues to evolve, turbocharging technology will play a vital role in meeting the demands for increased power and efficiency while reducing emissions. 

With ongoing advancements in electric turbocharging and other innovative turbo technologies, the future looks promising for turbocharged engines.

Conclusion

Turbochargers have revolutionized the world of internal combustion engines, offering a more efficient and powerful alternative to naturally aspirated engines. 

From their humble beginnings as "turbo superchargers" to their widespread use in various applications today, turbochargers have come a long way.

Whether it's a single turbocharger, a twin-turbo setup, or a cutting-edge electric boosting system, turbochargers continue to push the boundaries of what's possible in engine performance and efficiency. 

As technology evolves, turbochargers will play an integral role in meeting the demands of modern vehicles for power, fuel economy, and reduced emissions.

Next time you're behind the wheel of a turbocharged car, take a moment to appreciate the engineering marvel that is the turbocharger. It's a testament to human ingenuity and the never-ending quest for more power and efficiency in our vehicles.