Stratified charge engine with turbocharger

摘要

In an embodiment, a method for turbocharging a stratified charge engine includes flowing, in a turbocharged mode, exhaust gas from the engine into a turbocharger based on the engine having a load greater than a threshold load and the engine operating in a first range of engine speeds, the threshold load comprising a peak load for engine operation in a naturally-aspirated mode using a lean air-fuel mixture and providing, by the turbocharger while in the turbocharged mode, an increased amount of air to a combustion chamber in the engine based on the turbocharger receiving the exhaust gas. The method also includes restricting flow, in the naturally-aspirated mode, of the exhaust gas into the turbocharger based on at least one of: the engine having a load less than the threshold load or the engine operating in a second range of engine speeds, the second range being greater than the first range.

主权项

1. A method for turbocharging a stratified charge engine, the method comprising:
determining a current engine speed via a first sensor; determining a current load of the engine via a second sensor; determining a threshold load, the threshold load comprising a peak load for engine operation in a naturally-aspirated mode using a lean air-fuel mixture; determining a mode of operation between a turbocharged mode or a naturally-aspirated mode based on the current engine speed, the current load of the engine and the threshold load, the mode of operation being turbocharged mode when the stratified charge engine having a current load greater than the threshold load and the stratified charge engine operating in a first range of engine speeds, the mode of operation being the naturally-aspirated mode based on at least one of: the stratified charge engine having a load less than the threshold load and the stratified charge engine operating in a second range of engine speeds, the second range being greater than the first range; flowing, in a turbocharged mode, exhaust gas from the stratified charge engine into a turbocharger based; providing, by the turbocharger while in the turbocharged mode, an increased amount of air to a combustion chamber in the stratified charge engine based on the turbocharger receiving the exhaust gas, the increased amount of air substantially maintaining the lean air-fuel mixture for an increased amount of fuel provided to the combustion chamber; and restricting flow, in the naturally-aspirated mode, of the exhaust gas into the turbocharger by closing a flow control device.