A combustion pre-chamber assembly includes pre-chamber device body defining an annular plenum that is in fluid communication with the at least one bore that extends through the spark plug shell. The annular plenum is also in communication with at least one purging passage that extends from the annular plenum to an end surface of the pre-chamber device body. Residual exhaust gases in the annular volume of the spark plug are purged by fresh charge flow from the main combustion chamber as the piston approaches top dead center. The fresh charge flow that is provided to the annular plenum through the at least one purging passage and into the annular volume of the spark plug through the at least one bore through the spark plug shell.

A spark plug that prevents a decrease in strength of a member to which a mark is attached while ensuring a readability of the mark, and a method of manufacturing the spark plug. The spark plug is configured to ignite an air-fuel mixture in an internal combustion engine. The spark plug includes: a mark formed of an oxide film generated on a surface of a metallic member or is formed of the metallic member and the oxide film; and a coating material covering the whole mark and allowing transmission of light.

An ion chamber provides a current representative of its characteristics as affected by external conditions, e.g., clean air or smoke. A direct current (DC) voltage is applied to the ion chamber at a first polarity and the resulting current through the ion chamber and parasitic leakage current is measured at the first polarity, then the DC voltage is applied to the ion chamber at a second polarity opposite the first polarity, and the resulting current through the ion chamber and parasitic leakage current is measured at the second polarity. Since substantially no current flows through the ion chamber at the second polarity, the common mode parasitic leakage current contribution may be removed from the total current measurement by subtracting the current measured at the second polarity from the current measured at the first polarity, resulting in just the current through the ion chamber.

A combustor for a gas turbine engine includes a combustion chamber and a fuel igniter assembly. The combustion chamber is defined by an annular inner combustor liner and an annular outer combustor liner. The fuel igniter assembly is coupled to the combustor and extends radially outward from the outer combustor liner. The fuel igniter assembly includes an igniter housing configured to house a fuel igniter therein, and a heat-dissipating element coupled to the igniter housing. The heat-dissipating element includes a plurality of fins configured to dissipate heat from the fuel igniter assembly.

A compression-ignition type internal combustion engine that burns a gaseous fuel, improves an ignition performance not only at a center part of the combustion chamber but also at an outer edge part. The compression-ignition engine comprises an electromagnetic wave generator configured to generate an electromagnetic wave, a controller configured to control the electromagnetic wave generator, and a plasma generator comprising a boosting circuit that constitutes a resonator configured to boost the electromagnetic wave, a first electrode configured to receive an output from the boosting circuit, and a second electrode provided to a vicinity of the first electrode, and the plasma generator is configured such that the first electrode is extruded and exposed toward a combustion chamber of the internal combustion engine, and a plurality of plasma generators are provided.

An internal combustion engine includes a spark plug which protrudes into a combustion chamber. The spark plug has a central electrode and a ground electrode, and is configured such that a spark is generated between the central electrode and the ground electrode by electrical discharge. The spark plug has a vortex generator that separates an air flow near the ground electrode from the ground electrode and generates a vortex at a downstream side. The central electrode and the ground electrode are placed in a manner such that a spark or a flame deformed by an air flow flowing between the central electrode and the ground electrode enters the trailing vortex, or the spark penetrates through the inside of the trailing vortex.

A non-thermal equilibrium plasma ignition plug including a tubular metallic shell having an axial hole extending along an axial line, an insulator disposed in such a manner as to form a gap in cooperation with a wall surface of the axial hole at a forward end portion of the metallic shell, and a center electrode held at the center of the insulator, and generates nonequilibrium plasma in response to voltage applied thereto from a power supply. The insulator has a plurality of depressions or protrusions formed on a surface thereof which faces a discharge space therearound.

An engine includes an engine block with at least one cylinder bank including cylinder bores formed therein. A piston is reciprocatingly disposed in each of the cylinder bores. A crankshaft is rotatably mounted to the engine block. Connecting rods are rotatably attached to the crankshaft and are coupled to the piston. A cylinder head with intake valves and exhaust valves in fluid communication with the cylinder bores is mounted to each cylinder bank. At least one permanent magnet is disposed in a skirt of each piston. At least one electromagnet is positioned adjacent to the permanent magnet(s). A control system selectively provides an electrical current to the electromagnets to produce a desired magnetic field, wherein the magnetic field of the electromagnets cooperates with a magnetic field of the permanent magnets to affect a motion of the piston in respect of the engine block.

An engine includes an engine block with at least one cylinder bank including cylinder bores formed therein. A piston is reciprocatingly disposed in each of the cylinder bores. A crankshaft is rotatably mounted to the engine block. Connecting rods are rotatably attached to the crankshaft and are coupled to the piston. A cylinder head with intake valves and exhaust valves in fluid communication with the cylinder bores is mounted to each cylinder bank. At least one permanent magnet is disposed in a skirt of each piston. At least one electromagnet is positioned adjacent to the permanent magnet(s). A control system selectively provides an electrical current to the electromagnets to produce a desired magnetic field, wherein the magnetic field of the electromagnets cooperates with a magnetic field of the permanent magnets to affect a motion of the piston in respect of the engine block.

An engine includes an engine block with at least one cylinder bank including cylinder bores formed therein. A piston is reciprocatingly disposed in each of the cylinder bores. A crankshaft is rotatably mounted to the engine block. Connecting rods are rotatably attached to the crankshaft and are coupled to the piston. A cylinder head with intake valves and exhaust valves in fluid communication with the cylinder bores is mounted to each cylinder bank. At least one permanent magnet is disposed in a skirt of each piston. At least one electromagnet is positioned adjacent to the permanent magnet(s). A control system selectively provides an electrical current to the electromagnets to produce a desired magnetic field, wherein the magnetic field of the electromagnets cooperates with a magnetic field of the permanent magnets to affect a motion of the piston in respect of the engine block.