Modeling of transport and chemistry in channel flows of automotive catalytic converters

Provided is an exhaust article (catalyst) coated on a single substrate, such as a monolithic honeycomb having a plurality of channels along the axial length of the catalyst. Different washcoat compositions are deposited along the length the channel walls of the substrate beginning from either the inlet or outlet axial end of the substrate to form inlet and outlet catalyst layers, respectively. In the coating process, the channel walls are coated with catalyst washcoat compositions to lengths that are less than the substrates' axial length. The architecture of the resulting catalyst layers defines a plurality of zones along the length of the substrate. The properties of each zone of the catalyst can be optimized to address specific catalyst functions by manipulation of both the coating lengths and the catalyst washcoat compositions.

Multi-zone catalytic converter

Computation and measurement of flow and combustion in a four-valve engine with intake variations

A collecting exhaust port 18 provided in a cylinder head 12 is comprised of exhaust port sections 46 extending from exhaust valve bores 35 in cylinders 14, and an exhaust collecting section 47 in which the exhaust port sections 46 are collected. The cylinder head 12 includes a protrusion 49 projecting in an arch shape outside a side wall 11 1 of a cylinder block 11. The exhaust collecting section 47 of the collecting exhaust port 18 directly faces an inner surface of a side wall 12 1 of the protrusion 49. Water jackets J2 and J3 for cooling the protrusion 49 are provided in upper and lower surfaces of the protrusion 49 having the collecting exhaust port 18 defined therein. The water jackets J2 and J3 are not provided between the side wall 12 1 of the protrusion 49 and the exhaust collecting section 47. Thus, the compact cylinder head 12 having the collecting exhaust port 18 integrally provided therein can be formed, while avoiding the complication of the structure of a core.

Cylinder head structure in multi-cylinder engine

Transient modelling of flow distribution in automotive catalytic converters

Numerical Approach for Improving the Conversion Characteristics of Exhaust Catalysts Under Warming-Up Condition

An exhaust manifold comprising a plurality of exhaust pipes and a merging portion applies exhaust gas from each cylinder uniformly to an oxygen sensor in a merging portion at low speed thereby improving the durability of the oxygen sensor. A downstream forward end of each exhaust pipe of the exhaust manifold, when connected to an inlet wall of a merging case having the oxygen sensor mounted on a side thereof, is formed in the shape of a bell mouth for leading the exhaust gas to the oxygen sensor. Each exhaust pipe is fixedly welded to the merging case at a position upstream of the forward end of the bell mouth. An angle formed by lines perpendicular to tangential lines at starting and ending points of a curved portion of the bell mouth at the forward end of the exhaust pipe is set in the range of 45° to 75°. As a result, the bell mouth spreads over the whole interior of the merging case and reduces a flow rate of the exhaust gas, and part of the exhaust gas flows toward the oxygen sensor. The oxygen sensor is thus more evenly exposed to the exhaust gas and has increased durability.

Shigeki Sugiura

Papers

Numerical Approach for Improving the Conversion Characteristics of Exhaust Catalysts Under Warming-Up Condition

Exhaust manifold, for internal combustion engine, for improving durability of oxygen sensor at merging portion of exhaust manifold

New technology for reducing the power consumption of electrically heated catalysts

Numerical analysis of fuel behavior in a port-injection gasoline engine

Numerical Analysis of Flow in the Induction System of an Internal Combustion Engine -Multi-Dimensional Calculation Using a New Method of Lines