Aspects of the present invention relate to a valve seat (20) for a poppet valve of an internal combustion engine, wherein the poppet valve comprises a head and a stem behind the head, the valve seat comprising: an aperture (21) configured to form a seal with the head of the poppet valve when the poppet valve is in a closed position; and a peripheral body (22) defining, at least in part, one or more ports (23) shaped like e.g. grooves and sized to enable injection of liquid or gas from a cylinder head of the internal combustion engine into a gas stream behind the head of the poppet valve.

Aspects of the present invention relate to a valve seat (20) for a poppet valve of an internal combustion engine, wherein the poppet valve comprises a head and a stem behind the head, the valve seat comprising: an aperture (21) configured to form a seal with the head of the poppet valve when the poppet valve is in a closed position; and a peripheral body (22) defining, at least in part, one or more ports (23) shaped like e.g. grooves and sized to enable injection of liquid or gas from a cylinder head of the internal combustion engine into a gas stream behind the head of the poppet valve.

An exhaust gas system is provided for a transport refrigeration unit (TRU) engine. The exhaust gas system includes an exhaust system. The exhaust system includes a catalyst operable in a temperature range to catalyze exhaust gas produced in the TRU engine and flown through the exhaust system. The exhaust gas system further includes temperature sensors respectively disposed to sense exhaust gas temperatures upstream of and downstream from the catalyst, at least one of first, second and third valves which are proportionally controllable to moderate amounts of air provided to the TRU engine, fuel provided to the TRU engine and air provided to the catalyst, respectively, and a controller. The controller is configured to compare sensed exhaust gas temperatures with the temperature range and issue a proportional signal to the at least one of the first, second and third valves in accordance with results of the comparison.

An ammonia generating apparatus comprises a housing comprising a first end wall on which a reductant injector configured to insert a reductant into the housing is mountable. A heating coil assembly is disposed within the housing. A first end of the heating coil assembly is located proximate to a location of the first end wall where a reductant injector tip of the reductant injector is located when the reductant injector is mounted on the first end wall. The heating coil assembly is configured to generate heat sufficient to thermolyze the reductant to generate ammonia and reaction byproducts, in response to an electric current being passed therethrough. A hydrolysis catalyst can be disposed downstream of the heating coil assembly for catalyzing hydrolysis of the reaction byproducts into ammonia.

An ammonia generating apparatus comprises a housing comprising a first end wall on which a reductant injector configured to insert a reductant into the housing is mountable. A heating coil assembly is disposed within the housing. A first end of the heating coil assembly is located proximate to a location of the first end wall where a reductant injector tip of the reductant injector is located when the reductant injector is mounted on the first end wall. The heating coil assembly is configured to generate heat sufficient to thermolyze the reductant to generate ammonia and reaction byproducts, in response to an electric current being passed therethrough. A hydrolysis catalyst can be disposed downstream of the heating coil assembly for catalyzing hydrolysis of the reaction byproducts into ammonia.

An exhaust system includes an exhaust gas-carrying pipe and a bypass to the exhaust gas-carrying pipe. The bypass has at least one inlet pipe and at least one outlet pipe. An exhaust gas sensor is arranged in the bypass between the inlet pipe and the outlet pipe in such a way that exhaust gas flowing through the bypass flows through the exhaust gas sensor. An accelerator accelerates the gas flow downstream of the exhaust gas sensor and is coupled to the outlet pipe. At least one inlet portion extends from the inlet pipe to the exhaust gas sensor, the flow cross-section of which is smaller than the flow cross-section of the inlet pipe and opens into an inlet of the exhaust gas sensor.

An exhaust system includes an exhaust gas-carrying pipe and a bypass to the exhaust gas-carrying pipe. The bypass has at least one inlet pipe and at least one outlet pipe. An exhaust gas sensor is arranged in the bypass between the inlet pipe and the outlet pipe in such a way that exhaust gas flowing through the bypass flows through the exhaust gas sensor. An accelerator accelerates the gas flow downstream of the exhaust gas sensor and is coupled to the outlet pipe. At least one inlet portion extends from the inlet pipe to the exhaust gas sensor, the flow cross-section of which is smaller than the flow cross-section of the inlet pipe and opens into an inlet of the exhaust gas sensor.

A mixer is mounted in an aircraft. A rear end part of a cylindrical portion of the mixer is divided by a guide vane into a plurality of divided tubular portions. In the plurality of divided tubular portions, a notch nozzle is formed on an outer wall of the cylindrical portion. A plurality of guide holes are formed to extend from the outer wall of the cylindrical portion to a rear end surface of the guide vane.

An automatic purifying device for engine exhaust gases is disclosed. Exhaust gases flow through a necked portion to be speeded and the temperature of the exhaust gases is kept uniform after entering an exhaust inlet, and the speeded exhaust gases then pass through a flared mouth so as to be diffused through metal catalyst carriers and a straight-through ceramic filter or wall-flow filter, allowing the poisonous emissions such as nitrogen oxides (NOx) to collide with the metal catalyst carriers to generate high heat to ignite carbon particles, carbon monoxide, hydrocarbons, and the like which are then decomposed and reduced to nitrogen gas and water by added urea or ammonia in the middle of passing through the straight-through ceramic filter or wall-flow filter, where the generated water can then be discharged through a drain port, thereby decreasing pollution to the environment.

A two-stage venturi cooler comprises a first tubular conduit having a longitudinal axis, the first elongate tubular conduit having an exhaust gas inlet at one end, a mixed gas outlet at an opposing end, and a cooling gas inlet, wherein structures inside the first stage define a venturi that forms a column of mixed gas, wherein the column of mixed gas comprises a ring of exhaust gas surrounding a core of cooling gas; and a second tubular conduit that is coaxial with the first tubular conduit, wherein the second tubular conduit has a mixed gas inlet at one end and a mixed gas outlet at an opposing end, and wherein the mixed gas inlet is to receive the column of mixed gas and to surround the column of mixed gas with an entrained column of ambient air.