Methods and systems are provided for a cooling arrangement. In one example, a system comprises a separator arranged in a block coolant jacket. The separator fluidly separates an upper portion of the block coolant jacket from a lower portion of the block coolant jacket.

Various embodiments of the present disclosure are directed to an internal combustion engine cylinder head. In one example embodiment, the cylinder head includes a combustion chamber, a fire deck, an intermediate deck remote from a combustion chamber, a central receptacle that receives an injection or ignition device, at least one valve bridge, at least two adjacent gas exchange valves, a top-down cooling system, at least one first transfer opening, and at least one second transfer opening. The top-down cooling system including a first sub-cooling chamber and a second sub-cooling chamber. The at least one first transfer opening positioned between the first sub-cooling chamber and the second sub-cooling chamber. The at least one second transfer opening positioned between the first sub-cooling chamber and the second sub-cooling chamber is arranged in the region in the region of the at least one valve bridge between the at least two adjacent gas exchange valves.

Various embodiments of the present disclosure are directed to an internal combustion engine cylinder head. In one example embodiment, the cylinder head includes a combustion chamber, a fire deck, an intermediate deck remote from a combustion chamber, a central receptacle that receives an injection or ignition device, at least one valve bridge, at least two adjacent gas exchange valves, a top-down cooling system, at least one first transfer opening, and at least one second transfer opening. The top-down cooling system including a first sub-cooling chamber and a second sub-cooling chamber. The at least one first transfer opening positioned between the first sub-cooling chamber and the second sub-cooling chamber. The at least one second transfer opening positioned between the first sub-cooling chamber and the second sub-cooling chamber is arranged in the region in the region of the at least one valve bridge between the at least two adjacent gas exchange valves.

A cooling system for a cylinder head of an internal combustion engine includes a cylindrical seat configured to engage an exhaust valve, a first coolant jacket, and a first conduit. The exhaust valve seat defines an annular cooling passage extending along a circumference of the cylindrical seat. A wall of the cylindrical seat defines a first opening into the annular cooling passage and a second opening into the annular cooling passage, where the first opening is positioned diametrically opposite to the second opening. The first coolant jacket is positioned adjacent to a fire-deck of the internal combustion engine. The first conduit fluidly couples the first coolant jacket to the at least one of the first opening and the second opening to the annular cooling passage in the exhaust valve seat.

Aspects of the present disclosure are directed to, for example, a cylinder head for an internal combustion engine. In one embodiment of the present disclosure, the cylinder head includes at least one upper partial cooling chamber, a lower partial cooling chamber, an intermediate deck and at least one flow connection. The upper and lower cooling chamber are separated from one another by the intermediate deck. The intermediate deck having an element of single-wall design which extends into a combustion chamber and penetrates the intermediate deck. The at least one flow connection is positioned in the region of the element between the at least one upper and lower partial cooling chambers. The at least one flow connection formed by at least one recess on the element which tapers towards the one lower partial cooling chamber.

To find compromises in the relationship between the component costs of intake and exhaust valves and the downsizing of an engine and the relationship between the cooling performance and the followability of the intake and exhaust valves and coordinate these conflicting relationships as much as possible. A hollow valve encapsulating coolant having a good cooling function is used as an exhaust valve, which is exposed to a higher temperature environment than an the intake valve, to eliminate a disincentive to downsizing. In contrast, a hollow valve that has no coolant, relatively low component cost, light weight, and good followability is used as the intake valve, which does not need to have a better cooling function than the exhaust valve and needs to have better followability than the exhaust valve to improve combustion efficiency.

A combustion-chamber structure of an engine comprises a combustion chamber which is partitioned by a cylinder block, a cylinder head, a piston, an intake valve, and an exhaust valve. The intake valve (exhaust valve) comprises an intake valve body including an umbrella part having a valve head and a valve face, a heat-insulation layer provided at the valve head and having smaller heat conductivity than the valve body, a heat-barrier layer provided to cover the valve head with the heat-insulation layer and having smaller heat conductivity than the valve body and the heat-insulation layer, and a heat-diffusion layer provided between the heat-insulation layer and the heat-barrier layer and having larger heat conductivity than the heat-insulation layer and the heat-barrier layer. The heat-diffusion layer comprises a contact portion which contacts with the cylinder head when the intake valve is closed.

A combustion-chamber structure of an engine comprises a combustion chamber which is partitioned by a cylinder block, a cylinder head, a piston, an intake valve, and an exhaust valve. The intake valve (exhaust valve) comprises an intake valve body including an umbrella part having a valve head and a valve face, a heat-insulation layer provided at the valve head and having smaller heat conductivity than the valve body, a heat-barrier layer provided to cover the valve head with the heat-insulation layer and having smaller heat conductivity than the valve body and the heat-insulation layer, and a heat-diffusion layer provided between the heat-insulation layer and the heat-barrier layer and having larger heat conductivity than the heat-insulation layer and the heat-barrier layer. The heat-diffusion layer comprises a contact portion which contacts with the cylinder head when the intake valve is closed.

A cooling system for a cylinder head of an internal combustion engine includes a cylindrical seat configured to engage an exhaust valve, a first coolant jacket, and a first conduit. The exhaust valve seat defines an annular cooling passage extending along a circumference of the cylindrical seat. A wall of the cylindrical seat defines a first opening into the annular cooling passage and a second opening into the annular cooling passage, where the first opening is positioned diametrically opposite to the second opening. The first coolant jacket is positioned adjacent to a fire-deck of the internal combustion engine. The first conduit fluidly couples the first coolant jacket to the at least one of the first opening and the second opening to the annular cooling passage in the exhaust valve seat.

A coolant bottle defines a first chamber and a second chamber fluidly coupled to the first chamber at a valve seat. The first chamber is fluidly coupled to a source of heated engine cooling fluid, while the second chamber is fluidly coupled to an engine water pump. A thermally responsive actuator is disposed within the first chamber, and has a thermally actuated sliding member having a valve seat engaging surface. The thermally actuated sliding member is movable from a first open position to a second closed position when the coolant is above a first temperature. The thermally responsive actuator is disposed within the first chamber.