What and HowTurbocharger Works

Who do we owe turbochargers to? Alfred J. Büchi (1879–1959) worked at the Gebrüder Sulzer Engine Company in Winterthur, Switzerland, as an automobile engineer. His first idea, similar to the turbocharger I depicted above, used an exhaust-driven turbine shaft to power a compressor that blasted additional air into an engine's cylinders. He invented the turbocharger in the years leading up to World War I and patented it in Germany in 1905, but he didn't stop working on better versions until he died four decades later.

Have you ever seen automobiles speeding by you, their tailpipes spewing sooty fumes? It's evident that exhaust fumes pollute the air, but it's less obvious that they waste energy at the same time. The exhaust is a combination of heated gases being pumped out at high speeds, and all of the energy it contains—both heat and motion (kinetic energy)—is being wasted. Wouldn't it be cool if the engine could somehow capture that wasted power and use it to accelerate the car? A turbocharger accomplishes precisely that.If you understand how a jet engine works, you'll have a good knowledge of how a turbocharger works in a car. A jet engine draws cold air in from the front, compresses it into a chamber where it burns with fuel, and then shoots hot air out the rear. As the heated air escapes, it screams past a turbine (which looks like a little metal windmill) that drives the compressor (air pump) at the engine's front. This is the part that forces air into the engine to ensure optimal fuel combustion. A car's turbocharger works on the same principle as a piston engine.The exhaust gas is used to power a turbine. This rotates an air compressor, which forces more air (and oxygen) into the cylinders, allowing them to burn more fuel each second. As a result, a turbocharged vehicle may generate greater power (which is another way of saying "more energy per second"). A supercharger (or "mechanically driven supercharger," as it's officially known) is similar to a turbocharger, but instead of being propelled by exhaust gases via a turbine, it's powered by the car's rotating crankshaft.