Exhaust Gas Recirculation Buildup Prevention via Segmented Manifold

Solution Overview

Problem

Existing engine technologies face challenges in reducing buildup in exhaust gas recirculation systems when mixing hydrocarbons with exhaust, as they often expose the recirculation system to hydrocarbons, leading to inefficiencies and potential damage.

Innovation Solution

The method involves using a barrier to separate fuel-included exhaust gas from non-recirculating exhaust gas, allowing only non-fuel-included exhaust to enter the recirculation tube, thereby minimizing exposure and preventing buildup in the exhaust gas recirculation system.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If hydrocarbons are injected into the exhaust system to reduce buildup in aftertreatment systems, then regeneration of aftertreatment devices is improved, but the exhaust gas recirculation system is exposed to hydrocarbons causing buildup and inefficiency

Engineering Contradiction:

Improveaftertreatment system regenerationVSAvoidhydrocarbon exposure to recirculation system

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The exhaust system is segmented into separate pathways: a first exhaust manifold for recirculation and a second exhaust manifold for aftertreatment regeneration. This segmentation allows hydrocarbons to be injected only into the second manifold's exhaust stream, preventing hydrocarbon exposure of the recirculation system while maintaining aftertreatment regeneration capability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A hydrocarbon injection device is introduced as an intermediary component into the second exhaust manifold. This intermediary device enables controlled hydrocarbon addition to the exhaust stream destined for aftertreatment, while the physical separation prevents these hydrocarbons from reaching the recirculation system through the first exhaust manifold.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Object-affected harmful factors

If separate exhaust gas pipes are used to route recirculation and aftertreatment exhaust separately, then hydrocarbon exposure to recirculation system is minimized, but device complexity increases

Engineering Contradiction:

Improvehydrocarbon exposure to recirculation systemVSAvoidexhaust system configuration

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The exhaust system is segmented into separate pathways: a first exhaust manifold for recirculation and a second exhaust manifold for aftertreatment regeneration. This segmentation allows hydrocarbons to be injected only into the second manifold's exhaust stream, preventing hydrocarbon exposure of the recirculation system while maintaining aftertreatment regeneration capability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The engine's existing fuel injection system is utilized for in-cylinder dosing of hydrocarbons into the exhaust stream. This multi-functional approach allows the fuel injection system to serve both its primary combustion function and the secondary function of hydrocarbon dosing for aftertreatment regeneration, reducing the need for entirely separate injection infrastructure.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentEP2079907B1Method for hydrocarbon injection into an exhaust system

Publication Date: 2014.02.26 CUMMINS INC

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AI summary

The present invention generally relates to engines, and, more particularly, to an exhaust system for reducing buildup in an exhaust gas recirculation system when mixing hydrocarbons with exhaust.