Diesel Exhaust Filter

Cummins 1: Michael ErhardtPatrius RobinsonTedrick RollingsJonathan Whitaker

Outline

Project Objective Background Conceptual Ideas

Decision Matrix Final Design

Proposed Solution Future

Spring Proposal Conclusion Questions

Project Objective

Design a sensor or system capable of measuring the amount of soot in a diesel soot filter.

Should be mass production capable cost effective.

Accuracy = +/- 0.5 g of soot per liter of filter.

This can be accomplished by either measuring the soot flowing into the filter, or measuring the amount of soot in the filter, and so on…..

Background Introduction Diesel Engines Properties of

Diesel Exhaust Diesel Soot

Filters

Cummins 610 Turbo Diesel

Background Info

Diesel Engine Characteristics Compressed Air Intake High Compression

Ratio Direct Fuel Injection

Cummins On-Highway Class

 

HowStuffWorks.com

Background Info

Diesel fuel = mixture of many different hydrocarbon molecules.

Combustion forms a complex mixture of hundreds of organic and inorganic compounds

Components Include are: Carbon dioxide Oxygen Nitrogen Water vapor Carbon monoxide Nitrogen compounds Sulfur compounds Low-molecular-weight

hydrocarbons

Background Info

Diesel Particulate Filter (DPF)

Cordierite Filter: refractory ceramic

Semi-Porous Adsorbent

Manufactured via extrusion process as a whole piece (monolithic)

Cordierite Filter

Background Info

Conceptual Designs

ConstantAppliedVoltage

Ammeter(Measures Current)

Wiring

Particulates (Soot)

CordieriteFilter

Power Supply(Supplies Voltage)

Vehicle Stack

Exhaust

Concept #1: Force Measuring System

Idea #2: Continuous Dilution Method

Idea #3: Temperature Monitoring

Idea #4: Particulate Measurement through Electrical Current Analysis

Idea #5: Incandescence Soot Measurement

Conceptual Designs

Decision Matrix Factor quantifying system:

1 – Very Poor 2 – Poor 3 – Average 4 – Good 5 – Excellent

Largest Total: Most reasonable idea Concept 3 was selected to be the most possible idea using the

decision matrix.

Cost

Production

Time

Idea

Complexity

Mass

Production

Specific

Factors

1 3 4 3 4 3 17

2 1 2 3 4 2 12

3 5 4 5 4 3 21

4 3 3 4 3 4 17

5 1 3 2 3 4 13

Concept #

FACTORS (1 - 5)

TOTAL

Proposed Solution:Design Development

Temperature Monitoring 1st Step: Validate the scientific principles used to formulate

this concept. Basic thermodynamic principle: as an object gains more

mass it will be more difficult to raise its temperature.

Soot

Filter

AirAir

Soot(1-η)

Energy Equation

CV

in out

dEQ W h m h m

dt

k Ph h E E

Becomes

CV

in out

d m uQ m h m h

dt

Component Breakdown

CV filter sootm m m CV filter sootU U U

filter sootCVd U UdU

dt dt

Simpler Modeling

Air in in out outCV Air soot soot soot soot

dTmC Q m h m h m h

dt

Proposed Solution: Measurement System

Temperature Sensor Placement Concern

RTD System

Future Work Based on the recommendations given to us by our

sponsor, the spring package will include:

One or two practical short term proposed solutions for the design issue.

A proposed research project (long-term solution).

Future Work: Projects

Short term proposed solutions for the design issue.

Competitive Company well-informed on the most current technology.

Conduct market analyses on current projects.

A proposed research project (long-term solution)

Cummins strives to be an innovator in the development of new technologies

Propose a scientifically feasible research project that will give Cummins the competitive edge

Engine Model: QSC8.3

Short Term Idea #1: Flame Ionization Detection Method

Flame Ionization Detection Method: The goal of this method is to allow for

real-time measurement. The exhaust gas is burned by a

hydrogen flame. The particulate matter (PM) concentration is

calculated based on the ion current that develops during the burning.

This method can continuously measure soot and soluble organic fraction (SOF) independently.

Flame Ionization Detection Method

The exhaust gas flow is split into two lines: One at 191°C One with the temperature adjusted to 52°C.

In the 52°C line, the solid components in the gas are removed by a filter, so only the gaseous components are fed to the FID. While the 191°C line, the gas is fed directly to the FID.

Flame Ionization Detection Method

The output from the 191°C line includes a pulse signal.

The signal is caused by carbon particles, and is proportional to the soot concentration.

The difference in the amount of vaporized hydrocarbons under each condition correlates to the SOF concentration.

Shows the results of the continuous PM measurement of a diesel vehicle running on a chassis dynamometer.

Short Term Idea #2: Pressure Drop of Segmented Diesel Particulate Filter

Pressure Drop of Segmented Diesel Particulate Filter This idea uses the flow resistance of a

segmented Diesel particulate filter.

A monolithic (Cordierite) filter left vs. a segmented (silicon Carbide) filter composed of 16 individual segments.

Pressure Drop of Segmented Diesel Particulate Filter

Both Cordierite and Silicon Carbide filters perform the same action of particulate filtration.

Flow passage through the filtration walls generates a fair amount of resistance to the flow.

Monolithic filter: Total filtration

area = sum of individual filtration areas of inlet channels.

Segmented filter: Not all inlet

channel walls are used

Pressure Drop of Segmented Diesel Particulate Filter

As far as filter flow resistance is concerned, a segmented design has two primary effects on the filter response: Reduces the net

filtration wall area of the filter.

It also slightly reduces the filter open frontal area.

Pressure drop of a segmented filter (dashed line) vs. a

monolithic filter

Long-Term Solution:Experimental Research Research Proposal

Determination of Optimal Location for Temperature Sensor Operation

Temperature Response

Conclusion & Questions?

Engine Model: QSK78