An engine exhaust system is accommodated in a counterweight portion while minimizing a change in an existing arrangement of an engine, a radiator, a radiator fan, and the counterweight portion. A body has a work device provided at the front and the counterweight portion at the rear. A ventilation path provided in the counterweight portion includes an elevated part formed between a bottom of a front portion and a bottom of a rear portion. An exhaust gas purification device and a muffler, both having a tube-like outer shape, are disposed in the rear portion of the ventilation path so as to be positioned one above the other with the purification device lying above the muffler. Pipes, which extend straight respectively from an end circumferential to surface of the purification device and an end circumferential surface of the muffler toward each other, are connected via flanges.

An engine exhaust system is accommodated in a counterweight portion while minimizing a change in an existing arrangement of an engine, a radiator, a radiator fan, and the counterweight portion. A body has a work device provided at the front and the counterweight portion at the rear. A ventilation path provided in the counterweight portion includes an elevated part formed between a bottom of a front portion and a bottom of a rear portion. An exhaust gas purification device and a muffler, both having a tube-like outer shape, are disposed in the rear portion of the ventilation path so as to be positioned one above the other with the purification device lying above the muffler. Pipes, which extend straight respectively from an end circumferential to surface of the purification device and an end circumferential surface of the muffler toward each other, are connected via flanges.

A work vehicle includes an engine, a post-processing device, and a cooling fan. The engine is mounted on a front portion of a travelling machine body. The post-processing device purifies exhaust gas of the engine. The cooling fan water-cools the engine. The cooling fan is located in front of the engine. The cooling fan, the engine, and the post-processing device are covered with a hood. The hood includes a shield. The shield covers a lower section of the post-processing device and one side of the engine. The shield is a perforated plate including a plurality of holes.

An exhaust muffler is made up of a plurality of layers including an exhaust passage pipe and expansion chambers, and includes a front assembly and a rear assembly sub-assembled separately from the front assembly. The front assembly includes a front exhaust passage pipe, a front muffler body disposed in covering relation to the outside of the front exhaust passage pipe and cooperating with the front exhaust passage pipe in making up double-walled pipes, and an exhaust valve disposed in the front exhaust passage pipe. The rear assembly includes a rear exhaust passage pipe and a rear muffler body disposed in covering relation to the outside of the rear exhaust passage pipe and cooperating with the rear exhaust passage pipe in making up double-walled pipes. There is thus provided an exhaust device for an internal combustion engine in which the accuracy of a position where the exhaust valve is installed is high.

A cooling system for an internal combustion engine in which an exhaust purification catalyst is arranged in an exhaust passage of the internal combustion engine, the cooling system including: a cooling unit configured to cool the exhaust passage upstream of the exhaust purification catalyst; a heat transmission inhibition portion configured such that heat transfer from the exhaust passage downstream of a location cooled by the cooling unit to the cooling unit is inhibited; and a heat radiation suppression portion that is provided in a curved section positioned in the exhaust passage from a location where the heat transmission inhibition portion is provided to the exhaust purification catalyst, and that is configured to suppress heat radiation transmitted from exhaust gas flowing in the curved section to an atmosphere around the curved section through curved section passage walls forming the curved section. With such a configuration, the decrease in exhaust gas temperature can be suppressed.

A cooling system for an internal combustion engine in which an exhaust purification catalyst is arranged in an exhaust passage of the internal combustion engine, the cooling system including: a cooling unit configured to cool the exhaust passage upstream of the exhaust purification catalyst; a heat transmission inhibition portion configured such that heat transfer from the exhaust passage downstream of a location cooled by the cooling unit to the cooling unit is inhibited; and a heat radiation suppression portion that is provided in a curved section positioned in the exhaust passage from a location where the heat transmission inhibition portion is provided to the exhaust purification catalyst, and that is configured to suppress heat radiation transmitted from exhaust gas flowing in the curved section to an atmosphere around the curved section through curved section passage walls forming the curved section. With such a configuration, the decrease in exhaust gas temperature can be suppressed.

A chemical heat storage device heats a subject to be heated existing in a pipe. The chemical heat storage device includes a reactor that generates heat by chemically reacting with a reaction medium, an absorber that causes an absorbent to absorb and stores the reaction medium, and a connection tube that is connected to the reactor and absorber, for the reaction medium to migrate through. The reactor includes a solid reaction material disposed along an outer peripheral surface of a place where the subject exists in the pipe and a casing that seals the reaction material so as to form a space along an outer peripheral surface of the reaction material. One end of the connection tube is open to the space.

A chemical heat storage device heats a subject to be heated existing in a pipe. The chemical heat storage device includes a reactor that generates heat by chemically reacting with a reaction medium, an absorber that causes an absorbent to absorb and stores the reaction medium, and a connection tube that is connected to the reactor and absorber, for the reaction medium to migrate through. The reactor includes a solid reaction material disposed along an outer peripheral surface of a place where the subject exists in the pipe and a casing that seals the reaction material so as to form a space along an outer peripheral surface of the reaction material. One end of the connection tube is open to the space.

An exhaust after-treatment assembly for an engine system is provided. The exhaust after-treatment assembly includes a housing having an inlet port, an outlet port, a catalyst disposed within a cavity defined by the housing, and a muffler assembly disposed within the cavity downstream of the catalyst. The muffler assembly includes one or more baffle plates disposed longitudinally spaced from one another within the housing to define at least a first resonator chamber and a second resonator chamber. Each of the baffle plates defines an openings aligned to one another about a longitudinal axis of the housing. Further, a resonator tube extends through the openings of the baffle plates and includes an inlet, a perforated portion and one or more outlet ports formed in a wall of the resonator tube. The perforated portion and the outlet ports, respectively in fluid communication with the second resonator chamber and the first resonator chamber.

An exhaust manifold includes an inner assembly that defines an exhaust gas passage and an outer housing assembly that surrounds the inner assembly. The outer housing assembly includes a first housing component configured for attachment to an engine and a second housing component configured for attachment to a turbocharger. The first and second housing components cooperate to surround the inner assembly. At least one fastener secures the first and second housing components together to generate a compressive force that seals and holds the inner assembly in a gas tight manner.