Diesel Exhaust Fluid Injector With Impact Structure

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Diesel engine exhaust after-treatment systems face issues with clogging and insufficient mixing of diesel exhaust fluid (DEF) due to crystal formation in the injector assembly, leading to reduced effectiveness in NOx emission reduction.

Innovation Solution

The diesel exhaust fluid injector assembly incorporates an impact structure with an inclined surface to disperse DEF and a shroud for insulation, eliminating the need for compressed air and preventing crystal formation, ensuring thorough mixing and efficient DEF distribution within the exhaust stream.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If DEF is injected into the exhaust stream using a conventional injector assembly, then the DEF should evaporate and mix with the exhaust stream, but crystal formation occurs in and around the exhaust outlet leading to clogging and insufficient mixing

Engineering Contradiction:

Improvemixing effectivenessVSAvoidcrystal formation

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The impact structure divides the injected DEF stream into smaller droplets by impacting it against the inclined surface, enhancing evaporation and mixing while preventing crystal formation through dispersion

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent replaces the conventional compressed air assistance system with a passive impact structure that uses the exhaust stream's own kinetic energy to atomize and disperse the DEF, eliminating the need for additional compression systems

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If an impact structure with inclined surface is added to disperse DEF, then mixing is improved, but device complexity increases

Engineering Contradiction:

ImproveDEF distributionVSAvoidinjector assembly structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The impact structure is integrated directly into the injector assembly body, combining the injection and dispersion functions into a single unified component rather than adding separate external devices

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The inclined impact structure passively utilizes the kinetic energy of the exhaust stream itself to atomize and disperse the DEF, eliminating the need for external compressed air systems or additional power sources

Inventive Principle:

Principle #25Self-service

3Temperature

If a shroud is added to insulate the injector body, then temperature control is improved preventing crystal formation, but device complexity increases

Engineering Contradiction:

Improveinjector body temperatureVSAvoidinjector assembly structure

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The shroud is integrated as part of the injector assembly housing, combining the insulation function with the existing structural components rather than adding a completely separate insulation system

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The shroud utilizes the existing exhaust stream environment and passive thermal insulation principles to maintain temperature, eliminating the need for active heating elements or complex temperature control systems

Inventive Principle:

Principle #25Self-service

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution effectively prevents crystal formation, ensures thorough mixing of DEF with exhaust gases, and maintains system performance by controlling temperature and flow, thereby enhancing NOx reduction efficiency without the need for additional air compression systems.

Implementation Method 1

an impact structure with an inclined impact surface that disperses and distributes the injected DEF into the engine exhaust stream

Methodology Applied

Scientific EffectImpact force: Impact Force

Implementation Method 2

a shroud that insulates the injector body

Methodology Applied

Scientific EffectThermal insulation: Thermal Insulation

Implementation Method 3

The injected DEF should evaporate and be thoroughly mixed with the exhaust stream

Methodology Applied

Scientific EffectEvaporation: Evaporation

Implementation Method 4

The injected DEF should evaporate and be thoroughly mixed with the exhaust stream

Methodology Applied

Scientific EffectConvection: Convection

Data Source

PatentUS9333466B2Diesel exhaust fluid injector assembly

Publication Date: 2016.05.10 CUMMINS CAL PACIFIC LLC

AI summary

A diesel exhaust fluid (DEF) injector assembly is provided for use in an engine exhaust after-treatment system. The DEF injector assembly includes an injector body having a fluid inlet and a fluid outlet that delivers the DEF to an engine exhaust stream. The DEF injector assembly may also include a valve that opens and closes the fluid outlet of the injector body. An exemplary DEF injector assembly further includes an impact structure with an inclined impact surface that disperses and distributes the injected DEF into the engine exhaust stream. Another exemplary DEF injector assembly further includes a shroud that insulates the injector body.