Abstract:
A control for an internal combustion engine that includes an exhaust gas recirculation system predicts at least one of the intake manifold temperature in EGR mode or an intake manifold pressure in EGR mode, but preferably both, during Boost mode operation. The predictions are relied upon to calculate an intake manifold critical temperate in EGR, at which condensation would occur. The control then compares the predicted temperate value with the calculated intake manifold critical temperature, and if the predicted value exceeds the calculated temperature, the control commands re-entry into exhaust gas recirculation mode.
Abstract:
An internal combustion engine includes an intake manifold supplying charge air to the cylinders. An exhaust manifold conducts exhaust gas away from the cylinders. A turbocharger including a turbine has an exhaust gas inlet connected with the exhaust manifold and also includes a compressor having an air inlet and outlet. The compressor air outlet is connected to the intake manifold to pressurize charge air during high power levels of engine operation. An EGR bypass connected between the turbine exhaust gas inlet and the intake manifold recirculates a portion of the exhaust gases to the cylinders. An intake air bypass adapted to recirculate a portion of compressor outlet air back to the compressor air inlet to reduce compressor outlet pressure and aid EGR flow through the EGR bypass to the cylinders during high power operation of the engine is connected between the compressor air outlet and the compressor air inlet.