Methods and systems are provided for a multi-fuel engine. In one example, a method includes adjusting an ignitability of a combustion mixture comprising ammonia and hydrogen. The combustion mixture may further include a carbon-containing fuel.

Methods and systems are provided for a multi-fuel engine. In one example, a method includes adjusting an ignitability of a combustion mixture comprising ammonia and hydrogen. The combustion mixture may further include a carbon-containing fuel.

A condensed water treatment device for an internal combustion engine is provided. The condensed water treatment device may include a condensed water tank, a condensed water supply device, and a condensed-water generation quantity controlling device. The condensed water treatment device may further include a computer. The computer by executing a computer program may function as a storage-water-quantity decrease controlling device and a storage-water-quantity increase controlling device.

A condensed water treatment device for an internal combustion engine is provided. The condensed water treatment device may include a condensed water tank, a condensed water supply device, and a condensed-water generation quantity controlling device. The condensed water treatment device may further include a computer. The computer by executing a computer program may function as a storage-water-quantity decrease controlling device and a storage-water-quantity increase controlling device.

A water recovery device includes: an exhaust gas pipe that is connected to a combustion device; a water generation unit that generates water by cooling exhaust gas in the exhaust gas pipe to condense water vapor in the exhaust gas; and a water container that stores water generated by the water generation unit. The water generation unit includes: an acoustic-wave generator that generates acoustic waves by absorbing heat from the exhaust gas pipe and giving the heat to working fluid, which transmits acoustic waves by oscillating, to cause the working fluid to oscillate; a transmission pipe that is internally filled with the working fluid and transmits acoustic waves generated by the acoustic-wave generator; and a cold-heat generator that generates cold heat to supply the cold heat to the exhaust gas pipe by receiving acoustic waves transmitted through the transmission pipe and giving heat to the acoustic waves.

A water recovery device includes: an exhaust gas pipe that is connected to a combustion device; a water generation unit that generates water by cooling exhaust gas in the exhaust gas pipe to condense water vapor in the exhaust gas; and a water container that stores water generated by the water generation unit. The water generation unit includes: an acoustic-wave generator that generates acoustic waves by absorbing heat from the exhaust gas pipe and giving the heat to working fluid, which transmits acoustic waves by oscillating, to cause the working fluid to oscillate; a transmission pipe that is internally filled with the working fluid and transmits acoustic waves generated by the acoustic-wave generator; and a cold-heat generator that generates cold heat to supply the cold heat to the exhaust gas pipe by receiving acoustic waves transmitted through the transmission pipe and giving heat to the acoustic waves.

An internally cooled internal combustion piston engine and method of operating a piston engine is provided, with the combination of liquid water injection, higher compression ratios than conventional engines, and leaner air fuel mixtures than conventional engines. The effective compression ratio of the engines herein is greater than 13:1. The engines may employ gasoline or natural gas and use spark ignition, or the engines may employ a diesel-type fuel and use compression ignition. The liquid water injection provides internal cooling, reducing or eliminating the heat rejection to the radiator, reduces engine knock, and reduces NOx emissions. The method of engine operation using internal cooling with liquid water injection, high compression ratio and lean air fuel mixture allow for more complete and efficient combustion and therefore better thermal efficiency as compared to conventional engines.

An internally cooled internal combustion piston engine and method of operating a piston engine is provided, with the combination of liquid water injection, higher compression ratios than conventional engines, and leaner air fuel mixtures than conventional engines. The effective compression ratio of the engines herein is greater than 13:1. The engines may employ gasoline or natural gas and use spark ignition, or the engines may employ a diesel-type fuel and use compression ignition. The liquid water injection provides internal cooling, reducing or eliminating the heat rejection to the radiator, reduces engine knock, and reduces NOx emissions. The method of engine operation using internal cooling with liquid water injection, high compression ratio and lean air fuel mixture allow for more complete and efficient combustion and therefore better thermal efficiency as compared to conventional engines.

An engine having a cylinder fastened to the engine ease with the biconcave internal partition, which divides the cylinder into the upper and bottom parts. Sparking plugs are mounted on both sides of the partition. The upper and the bottom parts of the cylinder have side scavenging channels which connect suction spaces to the working spaces of both parts of the cylinder. The upper and bottom parts of the cylinder have inlet and outlet orifices. Inside the upper and inside the bottom part of the cylinder and the upper and bottom piston are placed respectively, while both pistons are directed towards each other by the working surfaces. The pistons are connected by a rod that is led through the linear bearing that is embedded in the partition forming a seal. The connecting rod is fastened to the bottom piston and by its other end it is connected to the crankshaft.

An internal combustion engine includes an internal combustion engine interior and a lubricant disposed in the internal combustion engine interior. The lubricant lubricates a component disposed in the internal combustion engine interior and the lubricant is a water-containing lubricant. In an embodiment, the internal combustion engine interior is fluidically connected to an environment surrounding the internal combustion engine by a ventilation device where the ventilation device has a semipermeable membrane which is impermeable to water and water vapor.