An exhaust heat recovery apparatus includes: a housing having a first exhaust passage and a second exhaust passage, an exhaust inlet fitting, and an exhaust outlet fitting; a heat exchanger disposed in the first exhaust passage; and a switching valve having a slide gate which is movable in a longitudinal direction of the housing so as to allow a flow of exhaust gases to be switched between the first exhaust passage and the second exhaust passage, wherein the first exhaust passage is parallel to the second exhaust passage, and the slide gate is movable between the first exhaust passage and the second exhaust passage.

When it is determined that control of warm-up of a catalyst is necessary at the time of start of an engine, an ECU starts warm-up control. Initially, the ECU performs first processing for a first set time period. In the first processing, the ECU sets the engine to an idle state and fully opens a waste gate valve. When the first set time period has elapsed since the first processing was started, the ECU performs second processing. In the second processing, the ECU sets the engine to a prescribed rotation speed and fully closes the waste gate valve. When a second set time period has elapsed since the second processing was started, the ECU quits the second processing and quits warm-up control.

Methods and systems are provided for user controlled engine revving. In one example, the engine may be revved to a peak speed according to a target revving sequence in response to a user-initiated command. A revving sound may be provided in response to an input device, without demanding manual depression of an accelerator pedal.

The present invention relates to a control unit for a waste heat recovery system, wherein the waste heat recovery system is operated in a first mode of operation after a first condition is fulfilled and the system is operated in a second mode of operation after a second condition is fulfilled. The invention also relates to a method for starting an expansion device in a waste heat recovery system.

Methods and systems are provided for user controlled engine revving. In one example, the engine may be revved to a peak speed according to a target revving sequence in response to a user-initiated command. A revving sound may be provided in response to an input device, without demanding manual depression of an accelerator pedal.

The exhaust gas after-treatment system of an engine configured as a gas engine or as a dual-fuel engine includes a catalyst, that can be flowed through by exhaust gas, a control tube extending through a recess in the catalyst, which control tube is movable relative to the catalyst and is flowable through by exhaust gas, and an actuator which is equipped to move the control tube relative to the catalyst dependent on at least one operating condition of the engine and/or at least one operating condition of the exhaust gas after-treatment system such that in a first relative position of the control tube relative to the catalyst, the catalyst can be flowed through by exhaust gas but not the control tube, and in a second relative position of the control tube relative to the catalyst, the control tube can be flowed through by the exhaust gas but not the catalyst.

Embodiments described herein methods can be used in particulate filter regeneration, such as particulate filters used for filtering the exhaust of an engine, e.g., a diesel engine. Systems herein can be configured to dispense combustion gas(es) into housing were a particulate filter is contained and to ignite the combustion gases. Methods for conducting a safety verification process of such systems are disclosed, as well as methods for regenerating the filters. Still other embodiments are described.

A control system for an engine including a turbocharger disposed downstream of a plurality of cylinders. The control system includes an engine sensor configured to generate a signal indicative of an operational characteristic of the engine. The control system includes a first valve configured to control exhaust flow through a first set of cylinders from the plurality of cylinders. The control system includes a second valve configured to control exhaust flow through a second set of cylinders from the plurality of cylinders. The control system includes a controller communicably coupled to the engine sensor, the first valve, and the second valve. The controller is configured to receive the signal generated by the engine sensor. The controller is configured to actuate the first valve and the second valve based on the received signal. The first valve and the second valve are actuated to adjust exhaust flow received by the turbocharger.

An exhaust heat recovery apparatus includes: a housing having a first exhaust passage and a second exhaust passage, an exhaust inlet fitting, and an exhaust outlet fitting; a heat exchanger disposed in the first exhaust passage; and a switching valve having a slide gate which is movable in a longitudinal direction of the housing so as to allow a flow of exhaust gases to be switched between the first exhaust passage and the second exhaust passage, wherein the first exhaust passage is parallel to the second exhaust passage, and the slide gate is movable between the first exhaust passage and the second exhaust passage.

Apparatus for attenuating a sound level comprising an enclosure having an inlet and an outlet, where an exhaust flow director is positioned within the enclosure and fluidly coupled to the inlet and the outlet. The exhaust flow director comprises a plurality of overlapping vanes that directs the exhaust flow to attenuate the level of the sound produced by the exhaust.