When an amount of a backward tumble flow is smaller than an amount of a forward tumble flow, the intake-side valve recess is used as a first valve recess and the exhaust-side valve recess is used as a second valve recess. When the amount of the backward tumble flow is larger than the amount of the forward tumble flow, the exhaust-side valve recess is used as a first valve recess and the intake-side valve recess is used as a second valve recess. An inclination angle of the first valve recess is larger than an inclination angle of the second valve recess when comparing the inclination angle such that a height of the recess decreases gradually toward an inner side of a cross-section.

When an amount of a backward tumble flow is smaller than an amount of a forward tumble flow, the intake-side valve recess is used as a first valve recess and the exhaust-side valve recess is used as a second valve recess. When the amount of the backward tumble flow is larger than the amount of the forward tumble flow, the exhaust-side valve recess is used as a first valve recess and the intake-side valve recess is used as a second valve recess. An inclination angle of the first valve recess is larger than an inclination angle of the second valve recess when comparing the inclination angle such that a height of the recess decreases gradually toward an inner side of a cross-section.

A method of controlling a reciprocating internal combustion engine comprising: a cylinder defining a cavity having a first end and a second end; and a piston moveable within the cavity of the cylinder between the first end and the second end, the method comprising: receiving at least a first signal; determining a quantity of liquid air to be injected using at least the received first signal; controlling injection of the determined quantity of liquid air into the first end of the cavity at a first time when the piston is closer to the first end than the second end.

A method of controlling a reciprocating internal combustion engine comprising: a cylinder defining a cavity having a first end and a second end; and a piston moveable within the cavity of the cylinder between the first end and the second end, the method comprising: receiving at least a first signal; determining a quantity of liquid air to be injected using at least the received first signal; controlling injection of the determined quantity of liquid air into the first end of the cavity at a first time when the piston is closer to the first end than the second end.

A fuel injector assembly is disclosed. The fuel injector assembly may include a case that encloses a solenoid assembly. The fuel injector assembly may include one or more inlet passages, positioned on the case, to permit fluid to enter the case to cool the solenoid assembly. The fuel injector assembly may include one or more outlet passages, positioned on the case, to permit fluid to exit the case. The fuel injector assembly may include an annular protrusion positioned around a circumference of the case between the one or more inlet passages and the one or more outlet passages.

A fuel injector assembly is disclosed. The fuel injector assembly may include a case that encloses a solenoid assembly. The fuel injector assembly may include one or more inlet passages, positioned on the case, to permit fluid to enter the case to cool the solenoid assembly. The fuel injector assembly may include one or more outlet passages, positioned on the case, to permit fluid to exit the case. The fuel injector assembly may include an annular protrusion positioned around a circumference of the case between the one or more inlet passages and the one or more outlet passages.

A fuel injector assembly is disclosed. The fuel injector assembly may include a case that encloses a solenoid assembly. The fuel injector assembly may include one or more inlet passages, positioned on the case, to permit fluid to enter the case to cool the solenoid assembly. The fuel injector assembly may include one or more outlet passages, positioned on the case, to permit fluid to exit the case. The fuel injector assembly may include an annular protrusion positioned around a circumference of the case between the one or more inlet passages and the one or more outlet passages.

An engine includes an EGR device and a water-cooled heat exchanger. The water-cooled heat exchanger is provided on a downstream side of an EGR gas-introduction portion of an intake passage into which EGR gas is to be introduced and exchanges heat with gas flowing in the intake passage. A control device is programmed to execute condensed water-suppression control that supplies coolant having a temperature higher than the temperature of the gas heat-exchanged in the water-cooled heat exchanger to the water-cooled heat exchanger while a hybrid vehicle is traveling in a state in which the engine is stopped.

When an amount of a backward tumble flow is smaller than an amount of a forward tumble flow, the intake-side valve recess is used as a first valve recess and the exhaust-side valve recess is used as a second valve recess. When the amount of the backward tumble flow is larger than the amount of the forward tumble flow, the exhaust-side valve recess is used as a first valve recess and the intake-side valve recess is used as a second valve recess. An inclination angle of the first valve recess is larger than an inclination angle of the second valve recess when comparing the inclination angle such that a height of the recess decreases gradually toward an inner side of a cross-section.

A fuel reforming system for a vehicle intake and exhaust line that reforms fuel in a vehicle intake and exhaust line including an exhaust gas recirculation (EGR) apparatus that recirculates a portion of an exhaust gas of an engine and a recirculation line that transfers an exhaust gas that is recirculated by the exhaust gas recirculation apparatus to supply as an intake gas of the engine, may include a fuel reformer that mixes an exhaust gas that passes through the recirculation line with fuel and that reforms fuel that is mixed in the exhaust gas, wherein an insulation material is coated at a wall surface of the fuel reformer.