SAE 2014 On-Board Diagnostics Symposium

Technical Session Schedule

Thursday, September 11

Draft Schedule for On-Board Diagnostics Symposium - Day Three
(Session Code: OBD300)

Room TBD  ALL DAY

Time Paper No. Title
8:00 a.m. ORAL ONLY
Heavy Duty Keynote Presentation
Engines with Heavy Duty OBD were first introduced in 2010, and in 2013 the number of engines requiring HD OBD continued to expand. New and more challenging diagnostics continue to be added along with more stringent emission threshold limits.

This presentation will focus on the key lessons learned during the 2010 and 2013 product launches as well as discussing the creation of an effective organization with tools and processes to deliver OBD compliant products. Challenges with Heavy Duty OBD will also be discussed; including aftertreatment diagnostics and issues related to the differences in regulations between US and Europe. Finally, and most importantly the future of OBD will be discussed. How can we make OBD a win-win for the end-user customer and the environment by leveraging advanced diagnostics to improve uptime, and decrease total cost of ownership? Can the certification burden be reduced and how do we integrate OBD with new and emerging technologies?
Stephen John Charlton, Cummins Inc.
8:45 a.m. ORAL ONLY
Heavy Duty Update
This presentation will focus on OBD challenges specific to the Heavy Duty Market. Potential Solutions and countermeasures will also be discussed. Challenges discussed will include issues related to being a horizontal industry and how application variation can impact diagnostic performance. In addition, Heavy Duty product cost and engineering resources are being impacted by regulation differences between the US and Europe; as well as, an increasing amount of system and threshold monitoring requirements. Finally, fault isolation and repair verification will be addressed for the Heavy Duty Market.
Jeffrey Potts, Cummins Inc.
9:15 a.m. ORAL ONLY
J1939 Standards Update
Mark Stepper
9:45 a.m.
BREAK
10:15 a.m. ORAL ONLY
Partial Volume Monitoring for Urea Based SCR Catalysts
OBD emissions thresholds for diesel urea based SCR (selective catalytic reduction) catalyst have been driven down rapidly by regulatory authorities, and continue to be driven down with the LEV III regulations proposed by ARB. The accuracy of state of the art NOx sensing technology is not keeping pace with the OBD requirements, motivating the need to look for more advanced SCR monitoring approaches.

One approach that has been employed with success for gasoline three way catalyst monitors is the so –called partial volume monitor where only a portion of the catalyst is monitored with the assumption that that portion will be damaged first.

In this presentation we investigate the potential benefit of partial volume SCR monitoring and the applicability of the assumptions.
Michiel Van Nieuwstadt, Ford Motor Co.
10:45 a.m. ORAL ONLY
Journey of NO2 as a Feedgas from an Oxidation Catalyst to an SCR Catalyst - Is it Making it all the Way?
Selective Catalytic Reaction (SCR) of ammonia (NH3) and nitrogen-oxides (NOx) is a predominant technology used in modern diesel automotive applications as an exhaust aftertreatment technology to reduce NOx emissions below regulatory limits. One of the key solutions to improve the selective reaction of NOx with NH3 is the presence of optimal concentration of NO2 in the exhaust gas; many research papers have indicated ~ 30-50% NO2/NOx ratio would be required as feed gas to maximize SCR catalyst’s NOx reduction efficiency. This led to numerous innovative exhaust oxidation catalyst formulations to produce sufficient NO2 as SCR feed gas. As a result, the OBD legislative requirements have followed the technology advancement demanding the monitoring of the NO2 production by oxidation catalysts.

This presentation will focus on unexplored territory, where the engineering community, especially OBD leaders, will be keen to review and discuss the impact of urea injection on potential transformation of NO2 in the exhaust aftertreatment system. Since most research papers and laboratory experiments use synthetic test bench applied gaseous NH3 as a reductant to study the SCR system sensitivity, they have proven NO2 exhibits strong influence on NOx conversion. Limited number of experiments we conducted using liquid urea solution dosing and measuring NO2 downstream of urea dosing to study how the urea spraying, evaporation, mixing, hydrolysis and localized exhaust gas quenching is altering the NO2/NOx ratio just upstream of the SCR catalyst or at the very first couple of inches of the SCR system. This presentation will summarize such case studies including measurements taken using various emissions analyzers, showing how the effect of the oxidation catalyst on generating NO2 may be impacted along the urea mixing and hydrolysis length. As a conclusion we will suggest new areas of research to better understand the feed gas quality impact on SCR efficiency in real world conditions including measurement equipment, OBD and base control algorithm theories.
Harsha K. Nanjundaswamy, FEV Inc.
11:15 a.m. ORAL ONLY
Particulate Sensor Signal Processing and Interpretation for Particulate Filter Diagnostics
Lower emissions and OBD thresholds for particulates and a need for diagnostics that directly check for presence of particulates have motivated a shift in industry to particulate matter (PM) sensors for exhaust filter diagnostics. At present the most mature sensors are resistive types which accumulate particles between a pair of electrodes. To restore measurement capability the sensors are heated at regular intervals to remove accumulated particulates, leading to a periodic output. A somewhat unique challenge is posed by these devices in that they do not provide a measurement that directly correlates to a physical quantity indicating particulate levels. Most sensor manufactures provide parts which derive levels from the time required for the sensor to reach a threshold conductivity from a known clean state.

This talk considers the suitability of the accumulation time metric as an input to a particulate filter monitor and compares it to other possible approaches, including the rate of change of the sensor signal. Data and analysis are shown to compare these approaches for accuracy, repeatability, and the time required for a valid measurement both at a sensor and particulate filter monitor level. The potential for each method to provide robustness against noise factors to expected sensor response and drifts in part sensitivity over time is covered. The possibility of the various metrics to improve detection capability of leaking exhaust filters at lower thresholds is also considered.
Michael B. Hopka, Ford Motor Co.
11:15 a.m. ORAL ONLY
Are Hidden Diagnostics Inside a Smart Device Allowed?
Smart Devices contain microprocessors but do not have enough diagnostic content to categorize them as diagnostic emissions critical controllers. The next round of proposed OBD regulations will further define the diagnostic requirements of such devices. This presentation will provide a working definition of a hidden diagnostic. Furthermore, it will illustrate examples of several types of hidden diagnostics and their characteristics in an attempt to determine if they are allowed by the OBD regulations. The intent of the presentation is to teach and inform both vehicle and smart device manufacturers how to identify and characterize hidden diagnostics in order to avoid OBD non-compliant smart device behaviors.
Daniel Grenn, General Motors Vehicle Engineering Cntr.
11:45 a.m. ORAL ONLY
Heavy Duty Hybrid OBD Progress
Heavy Duty Hybrid OBD continues to be a topic of concern for heavy duty hybrid and engine manufacturers and their customers. This presentation will summarize the requirements derived from the OBD regulations that are applicable to heavy duty hybrids as well as the impacts of these requirements on existing and new designs, and the current progress towards understanding the test required and the OBD approval process. The presentation will provide an update on progress towards applying these requirements, overcoming the challenges that exist between hybrid and engine manufacturers to achieve OBD approval, and summarize the efforts in the SAE J1939 Hybrid Communication Task Force to standardize interfaces between hybrid power systems.
Christopher Charles Jones, BAE Systems Inc.
12:15 p.m. ORAL ONLY
Networking Lunch With Exhibits
1:30 p.m. ORAL ONLY
Novel Approach to Diagnose SCR Feedgas Quality Deterioration in Diesel Aftertreatment Systems
Selective Catalytic Reaction (SCR) of ammonia (NH3) and nitrogen-oxides (NOx) is a predominant technology used in modern diesel automotive applications as an exhaust aftertreatment technology to reduce NOx emissions below regulatory limits. One of the key solutions to improve the selective reaction of NOx with NH3 is the presence of optimal concentration of NO2 in the exhaust gas; many research papers have indicated ~ 30-50% NO2/NOx ratio would be required as feed gas to maximize the SCR catalyst’s NOx reduction efficiency. This led to numerous innovative exhaust oxidation catalyst formulations to produce sufficient NO2 as SCR feed gas. As a result, the OBD legislative requirements have followed the technology advancement demanding the monitoring of the NO2 production by oxidation catalysts.

This presentation will introduce a new concept to utilize primarily an advanced SCR NOx efficiency monitor to diagnose the SCR system as a whole. This concept’s key element is a so called SCR diagnostic coordinator which can schedule and execute various lower level diagnostics to pinpoint which component(s) may be responsible for the loss of SCR efficiency. For example the disadvantages of frequent DOC NMHC conversion monitoring execution are well known: fuel-oil dilution, excessive aging of DOC, DPF and SCR catalysts, surplus production of greenhouse gases, especially CO2 and N2O, potential NH3 slip, etc. While the OBD regulatory requirements force frequent execution of such diagnostics to fulfill in-use monitoring requirements, with the SCR coordinator the frequency of such a detrimental OBD function can be optimized.
Tamas Szailer, FEV Inc.
2:00 p.m. ORAL ONLY
OBD Considerations for Dual- and Bi-Fuel Heavy-Duty Engines
The U.S. heavy-duty commercial engine market is dominated by diesel-fueled engines. However, with a lower price and an abundant domestic supply, some fuels, such as compressed natural gas (CNG), are driving the market toward alternatives to the conventional diesel engine. With this price advantage, the market is growing quickly for both dedicated and dual-fuel natural gas engines. Dual- and bi-fuel heavy-duty engines benefit from the ability to retrofit on existing platforms and an ability to avoid dependence on an alternative fuel that may not yet have achieved a sufficient infrastructure. For these reasons, dual- and bi-fuel heavy-duty engine offerings are expected to see continued growth in the commercial engine market.

As more stringent OBD requirements for these engines are phased in over the next few years, with requirement for full OBD compliance in 2018, manufacturers must understand the impact these regulations will have on their base engine OBD strategies and calibration. This overview includes a summary of the current and upcoming OBD regulation requirements and focuses on the impact they may have on dual- and bi-fuel engines. These requirements will likely lead to an inability for retrofit companies to achieve OBD compliance without OE support.

The vast majority of dual- or bi-fuel systems on the market today are retrofit kits applied to Outside-Useful-Life (OUL) engines, which have the least certification requirements. With a significant amount of integrated strategy to support current HD OBD requirements for conventional HD engines, the retrofitter may not be able to apply a secondary controller for alternative fuel concepts without disrupting the OBD functionality.

If implementing a dual- or bi-fuel approach to an existing platform, OE manufacturers will also need to address impact of this new fueling and combustion system on their OBD monitors. Potential impacts may include the functionality and accuracy of monitors applied to the air, fuel, EGR and aftertreatment systems. For example, a diesel engine converted to dual- or bi-fuel operation can no longer use lambda as feedback for EGR control without modification, leading to a need for base engine and OBD strategy adjustment. In many cases, a parallel or switching approach with separate OBD strategy/calibration may be required.

An additional concern for alternative fueled engines utilizing natural gas is the emission of methane (CH4). While there are currently no OBD requirements in place for Green House Gas (GHG) emissions, it is likely that additional monitors will be required to ensure compliance with future regulations. As CH4 is considered to be a GHG with greater impact than carbon dioxide, any future regulations could greatly influence the OBD systems for those engines whose fuels have potential for excessive CH4 emissions. The known challenges of short circuiting air/fuel mixture with the currently common intake fumigation approach and poor conversion of CH4 with conventional catalyst formulations are potential impediments for success of some alternative fueled engines if OBD monitoring is required for GHG constituents in the future. Based on these concerns, it is critical that industry understands the impact new OBD regulations may have on current and future alternative fuel approaches and its ability to provide the market with powertrain alternatives that make use of currently abundant and lower cost fuels.
Claude Pilger, FEV Inc.
2:30 p.m.
BREAK
3:00 p.m. ORAL ONLY
Historical OBD Collaborative Presentation
This is a 90 minute talk surrounding historical OBD and will feature several industry experts.
Paul A. Baltusis, Ford Motor Co.