What purpose does a turbocharger serve in a reciprocating engine?

A turbocharger serves the critical function of increasing the air intake in a reciprocating engine, which directly enhances engine power. By using exhaust gases to spin a turbine and compress the incoming air, a turbocharger allows for more air to enter the combustion chamber. This additional air mix enables the engine to burn more fuel efficiently, leading to an increase in overall power output.

Increasing air density helps the engine produce more power without requiring a larger displacement. This is especially valuable at higher altitudes where the atmospheric pressure and consequently the air density is lower. Turbochargers help compensate for this loss by ensuring that the engine still receives adequate air for optimal combustion.

While options related to reducing emissions, cooling the engine, or improving fuel efficiency may occur as secondary benefits or effects of improved engine operation due to a turbocharger, the primary and most direct purpose of a turbocharger is to boost air intake, thereby enhancing power output.