turbocharging

Turbocharging is a method of forced induction used to increase an internal combustion engine’s power and efficiency by using exhaust gas energy to drive a turbine that compresses incoming air. The denser intake charge allows more fuel to be burned, producing more power without increasing engine displacement significantly. Turbocharged engines often deliver better fuel economy at part load and can provide substantial power gains at higher RPMs.

A turbocharger consists of a turbine and a compressor on a common shaft. Exhaust gases spin the turbine, which in turn drives the compressor to draw in and compress ambient air before it enters the engine. The compressed air is hotter, so an intercooler is commonly used to cool it and increase density. A wastegate or bypass valve regulates boost pressure to prevent over-boost, and electronic or hydraulic controls optimize response across operating conditions.

Technologies used with turbochargers include single-turbo, twin-turbo and sequential setups, as well as variable-geometry (or variable-nozzle) turbos that adjust the turbine’s effective area to improve throttle response and efficiency across a wider RPM range. Some systems employ electric auxiliaries or hybrid layouts to reduce lag and improve low-end response.

Advantages include increased power without a heavier engine, and potential fuel economy benefits from downsizing. Disadvantages can include turbo lag, added heat and thermal management needs, higher complexity and maintenance, and potential for higher NOx emissions if not properly managed. Modern turbocharged engines often couple direct injection, advanced engine controls, and aftertreatment systems to meet emissions and reliability targets.

Turbocharging is widely used in automobiles, aviation, and marine and industrial applications as a means to improve performance and efficiency.