Roots superchargers are primarily used in internal combustion engines to increase power output by forcing more air into the combustion chamber. This allows the engine to burn more fuel, resulting in a more powerful explosion and thus, more torque and horsepower.
How Roots Superchargers Work
Unlike turbochargers which use exhaust gases, Roots superchargers are mechanically driven by the engine's crankshaft, typically via a belt or gears. They function as positive displacement pumps, moving a fixed volume of air with each rotation of their meshing lobes. This forced induction process increases the air density entering the engine.
Key Applications and Benefits
The unique characteristics of the Roots-type blower make it particularly well-suited for specific applications, notably in passenger automobiles.
Based on the provided information:
- Effectiveness at Low Engine Speeds: A significant advantage of the Roots design is its effectiveness at developing positive intake manifold pressure (meaning pressure above atmospheric pressure) even at low engine speeds.
- Immediate Power: Because they are directly connected to the crankshaft, they provide boost instantaneously as soon as the engine starts turning, offering excellent low-end torque and response. This is often referred to as having no "turbo lag."
- Popularity in Passenger Cars: This ability to generate boost efficiently right off idle makes the Roots supercharger a popular choice for passenger automobile applications. It enhances drivability by providing strong acceleration from a standstill and during low-speed maneuvers.
- Simplicity and Reliability: The design of the Roots blower is relatively simple, contributing to its widespread use and potential reliability.
In summary, Roots superchargers are widely used to provide a broad power band with a strong emphasis on low-end torque and immediate throttle response, making them a favored choice for street performance in passenger vehicles where quick acceleration from low speeds is desired.
