Methods and systems are provided for reducing pumping losses during a partial deactivation. In one example, a method may include applying negative pressure to a deactivated cylinder group to remove gases trapped therein while an activated cylinder group continues to combust.

A bottoming cycle power system includes an expander disposed on a crankshaft. The expander being operable to receive a flow of exhaust gas from a combustion process and to rotate the crankshaft as the exhaust gas passes through. An absorption chiller system has a generator section having a first heat exchanger to receive the flow of exhaust gas from the expander and to remove heat from the exhaust gas after the exhaust gas has passed through the expander. An evaporator section has a second heat exchanger to receive the flow of exhaust gas from the generator section and to remove heat from the exhaust gas after the exhaust gas has passed through the generator section. A compressor is disposed on the crankshaft and connected to the flow of exhaust gas. The compressor is operable to compress the exhaust gas after the exhaust gas has passed through the second heat exchanger.

An internal combustion engine includes a pre-chamber. In another aspect, pressure within a pre-chamber is equal to or greater than pressure within a main combustion chamber at least prior to ignition in the main combustion chamber. In yet another aspect, internal combustion engine control software automatically controls pressure within a turbulent jet ignition pre-chamber, controls a valve-actuator to admit a fuel-air charge into the pre-chamber, and causes an igniter to initiate combustion in the pressurized pre-chamber. This also permits the rate of combustion to be controlled in the primary chamber regardless of the air-fuel ratio or the diluent fraction in the main chamber. Another aspect employs a pre-chamber purge pump with separate air and fuel injection.

An internal combustion engine includes a pre-chamber. In another aspect, pressure within a pre-chamber is equal to or greater than pressure within a main combustion chamber at least prior to ignition in the main combustion chamber. In yet another aspect, internal combustion engine control software automatically controls pressure within a turbulent jet ignition pre-chamber, controls a valve-actuator to admit a fuel-air charge into the pre-chamber, and causes an igniter to initiate combustion in the pressurized pre-chamber. This also permits the rate of combustion to be controlled in the primary chamber regardless of the air-fuel ratio or the diluent fraction in the main chamber. Another aspect employs a pre-chamber purge pump with separate air and fuel injection.

An internal combustion engine includes a cylinder defining a combustion chamber enclosed by a cylinder wall, a piston that is arranged inside the combustion chamber and moveable in a reciprocating motion away from and towards a crankshaft, and at least one first scraper ring defining an oil scraper ring that is arranged between the piston and the cylinder wall and configured to scrape oil off from the cylinder wall when the piston moves towards the crankshaft. The internal combustion engine further includes at least one second scraper ring defining a condensation fluid scraper ring that is arranged between the piston and the cylinder wall and configured to scrape a condensation fluid off from the cylinder wall when the piston moves away from the crankshaft.

Methods and systems are provided for reducing pumping losses during a partial deactivation. In one example, a method may include flowing vacuum to a deactivated cylinder group to remove gases trapped therein while an activated cylinder group continues to combust.

In a method for operating a combustion engine in which exhaust gas located in a cylinder during an outlet cycle thereof is ejected from the cylinder and supplied to an exhaust system, a particularly high specific power output of the combustion engine and/or a particularly low specific fuel consumption are to be made possible, in a particularly simple and reliable manner. For this purpose, according to the invention, in a first cycle phase of the outlet cycle the pulse of the exhaust gas pressure wave flowing out of the cylinder is transmitted in whole or in part to the primary side of an exhaust gas charge pump, before the exhaust gas is passed to the exhaust system in a second cycle phase of the outlet cycle.

An internal combustion engine includes a cylinder defining a combustion chamber enclosed by a cylinder wall, a piston that is arranged inside the combustion chamber and moveable in a reciprocating motion away from and towards a crankshaft, and at least one first scraper ring defining an oil scraper ring that is arranged between the piston and the cylinder wall and configured to scrape oil off from the cylinder wall when the piston moves towards the crankshaft. The internal combustion engine further includes at least one second scraper ring defining a condensation fluid scraper ring that is arranged between the piston and the cylinder wall and configured to scrape a condensation fluid off from the cylinder wall when the piston moves away from the crankshaft.