Detroit Diesel Corporation

Caterpillar Inc.

Sameer Bhargava

Ravishankar Ramamurthy

Scott Alan Leman

James J Faletti

Steven J Funke

Joshua C Ruedin

Matthew G Mickiewicz

Brian Andrew Lewallen

Phillip F Rimnac

Laurentiu Vaduva

A control and method for an internal combustion engine that includes an exhaust gas recirculation system to predict an intake manifold critical temperature (dew point) at which condensation would occur upon entry into exhaust gas recirculation. The control calculates the intake manifold critical temperature (IMT_Critical) as a function of predetermined, sensed or assumed values by processing an equation whose variables are occupied by the values. The control commands adjustments of exhaust gas recirculation operation in response to the calculation, preferably after the actual intake manifold temperature exceeds the IMT_Critical for a predetermined time.

Influence of engine parameters on condensation protection strategies

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.

Re-entry strategy from boost mode to EGR mode

A system and method for controlling an internal combustion engine to reduce or eliminate formation of EGR condensate monitor current ambient and operating conditions to determine whether conditions are favorable for condensation of EGR gases, and control the engine accordingly to avoid condensation, preferably by increasing the intake manifold temperature. The intake manifold temperature may be increased by redirecting some or all of the EGR flow to avoid the EGR cooler. Alternatively, or in combination, some or all of the charge air may be redirected to bypass the charge air cooler and/or redirected from the outlet of the turbocharger compressor to the intake, effectively increasing the intake air temperature and resulting in a corresponding increase of the intake manifold temperature. Conditions favorable for condensation may be determined based on engine speed and load, ambient temperature, manifold pressure, scheduled or actual EGR flow rate and scheduled or actual air/fuel ratio.

Condensation control for internal combustion engines using EGR

A system and method for controlling combustion engine compression braking having the variable timing of the dwell period of at least one exhaust valve by an electronic control module within each one of the engine cylinders during a braking event as well as the variable timing of the commencement or onset of the braking event. The system and method thus facilitate the proper performance of the braking event as a function of engine speed and prevents interference or physical impact with the cam driving elements used for achieving the normal or regular exhaust valve event.

Electro-hydraulic compression release brake

A method of operating a diesel engine is disclosed. The method includes the step of sensing a temperature level associated with the engine. The method further includes the step of positioning the intake valve in the open position during an exhaust stroke of the engine if the temperature level is below a predetermined threshold value, whereby heated exhaust gases advance into the intake conduit during the exhaust stroke so as to heat intake air located in the intake conduit prior to the intake air advancing into the combustion chamber during a subsequent intake stroke. The method yet further includes the step of positioning the intake valve in the closed position during the exhaust stroke if the temperature level is above the predetermined threshold value, whereby heated exhaust gases are prevented from advancing into the intake conduit during the exhaust stroke. A diesel engine is also disclosed.

Growing community of inventors

Canton, MI, United States of America

Sameer Bhargava