An exhaust structure of an internal combustion engine having an exhaust passage communicating between an exhaust port and an exhaust pipe. The exhaust structure includes a heat insulating component covering an inner wall of the exhaust port, the heat insulating component includes a first abutting portion disposed at a first side of the heat insulating component at a combustion chamber side and abutting an inner wall of the exhaust port, a second abutting portion disposed at a second side of the heat insulating component at an exhaust pipe side and abutting the inner wall, and a middle section disposed between the first side and the second side. A gap is formed between the middle section and the inner wall, and a bent portion connecting the middle section and the first abutting portion is bending toward the inner wall of the exhaust port from the middle section.

An insulated exhaust port liner of a cylinder head assembly for fluidly connecting to an internal combustion engine of a motor vehicle includes a sealing layer. The sealing layer has a first surface defining a passage for fluidly connecting to the internal combustion engine and receiving exhaust gas. The sealing layer further includes a second surface opposite to the first surface. The liner further includes a thermal barrier layer coated onto the second surface of the sealing layer. The thermal barrier layer is a porous non-woven material for supporting the sealing layer on the cylinder head and reducing a transfer of heat from the sealing layer to the cylinder head.

An insulated exhaust port liner of a cylinder head assembly for fluidly connecting to an internal combustion engine of a motor vehicle includes a sealing layer. The sealing layer has a first surface defining a passage for fluidly connecting to the internal combustion engine and receiving exhaust gas. The sealing layer further includes a second surface opposite to the first surface. The liner further includes a thermal barrier layer coated onto the second surface of the sealing layer. The thermal barrier layer is a porous non-woven material for supporting the sealing layer on the cylinder head and reducing a transfer of heat from the sealing layer to the cylinder head.

The disclosure relates to a cylinder head for covering a combustion chamber of an internal combustion engine. The cylinder head comprises at least one material recess for heat isolation, which is formed in a main body of the cylinder head and is arranged between a fluid-guide channel and a cooling channel. The material recess can be produced e.g. directly during the shaping (e.g. casting or pressing) of the cylinder head and/or thereafter. For example, in the event that exhaust gas is guided through the fluid-guide channel, a significantly lower heat input occurs from the hot exhaust gas into the cooling fluid. In addition, the thermal decoupling via the material recess leads to the hot exhaust gas cooling to a lesser degree in the fluid-guide channel.

An exhaust structure of an internal combustion engine having an exhaust passage communicating between an exhaust port and an exhaust pipe. The exhaust structure includes a heat insulating component covering an inner wall of the exhaust port, the heat insulating component includes a first abutting portion disposed at a first side of the heat insulating component at a combustion chamber side and abutting an inner wall of the exhaust port, a second abutting portion disposed at a second side of the heat insulating component at an exhaust pipe side and abutting the inner wall, and a middle section disposed between the first side and the second side. A gap is formed between the middle section and the inner wall, and a bent portion connecting the middle section and the first abutting portion is bending toward the inner wall of the exhaust port from the middle section.

A cylinder head with connected exhaust manifold of an internal combustion engine the cylinder head has an exhaust duct ending at a cylinder head connecting face to which the exhaust manifold is connected. A flange bushing insert having a bushing part and an end-side flange, is inserted into an exhaust gas duct of the cylinder head. The bushing part has a radially protruding, circumferential bead as a spacer and sealing element that bears against the exhaust duct inner wall. The flange projects at the end of the flange bushing insert and is clamped between the cylinder head connecting face and the exhaust manifold connecting face such that a circumferential insulating gap.

An exhaust port liner, which may include a superalloy and may be manufactured by an additive manufacturing process, includes a monolithic structure including an outlet disposed an angle relative to an inlet, and a sidewall defining a cavity to provide enhanced thermal performance in reciprocating internal combustion engines. A cylinder head of an internal combustion engine may include a cylinder head frame, and the exhaust port liner may be disposed proximate the frame inner mounting surface, with an outer surface of the exhaust port liner conforming to an inner mounting surface of the cylinder head frame.

An exhaust port liner, which may include a superalloy and may be manufactured by an additive manufacturing process, includes a monolithic structure including an outlet disposed an angle relative to an inlet, and a sidewall defining a cavity to provide enhanced thermal performance in reciprocating internal combustion engines. A cylinder head of an internal combustion engine may include a cylinder head frame, and the exhaust port liner may be disposed proximate the frame inner mounting surface, with an outer surface of the exhaust port liner conforming to an inner mounting surface of the cylinder head frame.

A cast cylinder head having a port lined with an insulating sleeve is provided. The insulating sleeve includes an inner sleeve disposed within an outer sleeve defining an insulating gap between the inner sleeve and outer sleeve. The inner sleeve includes an inlet flange surface and an outlet flange surface joined to an inlet flange surface and an outlet flange surface of the outer sleeve, thereby providing a sealed insulating gap. The insulating gap may contain an insulating material or a vacuum. The outer sleeve includes an exterior surface onto which a molten metal is casted to form the cast cylinder. The exterior surface of the outer-sleeve includes a shoulder to fix the insulating sleeve within a fixed predetermined position within the casting.

Methods and systems are provided for thermally insulating an integrated exhaust manifold for a cylinder head of an applied-ignition, liquid-cooled internal combustion engine. In one example, a method may include regional insulation at a collection point where individual exhaust lines and/or partial exhaust lines merge to form an overall exhaust line within the cylinder head. The regional insulation may be formed integrally with a seal and coupled to an outlet flange of the cylinder head and may include a series of tongue-like projections that extend from the cylinder head outlet flange toward the cylinder exhaust lines.