Turbocharging system for an internal combustion engine

摘要

A turbocharging system for an internal combustion engine improves performance and efficiency under low-speed, high-load operating conditions by adding secondary air to the exhaust gas upstream of the turbocharger. The secondary air combusts with unburned fuel contained in the exhaust gas to increase the temperature and pressure of the exhaust gas driving the turbocharger. Secondary air is added only when the exhaust gas temperature is above a prescribed temperature and the air-fuel ratio of the exhaust gas is below a prescribed ratio.