SAE 2014 Light Duty Emissions Control Symposium
Technical Session Schedule
Wednesday, December 10
Sensors, Modeling, Control
(Session Code: LDD600)
Room Salon ABCD 1:00 p.m.
|| ORAL ONLY
|Particle Sensors for Exhaust OBD
Spark-plug sized particle sensors are developing rapidly due to onboard diagnostics (OBD) regulations demand in the US and Europe and eventually worldwide. Particle sensors will be one of the key enablers for exhaust particle filters to continue their success in keeping particle emissions below or equal to the regulatory limits not only in brand new vehicles, but also in vehicle lifetime. Beyond OBD, particle sensors have numerous applications in engine research and development, retrofit technologies, environmental research and modeling, and instrumentations.
Before spreading the use of particle sensors in the market place, it is critical that their performance and durability are well understood. The performance of particle sensors is critical as we need to understand what property of particulate matter (PM) do they measure (mass, number, surface area, size, etc…), the fundamentals of such measurement and the dependent variables, and how it relates to our current measurement method of PM. After performance characterization of particle sensors, it is equally critical to demonstrate that such performance is durable. Without such important information on performance and durability, PM measurement with particle sensors will lose its credibility in being able to protect human health and the environment onboard vehicles in OBD applications.
The focus of this paper is on particle sensor performance and durability. First, we will describe available particle sensor technologies and principle of operation. Second, we will discuss the approach taken to characterize sensor performance and durability in an engine test cell facility. Finally, a limited set of normalized results will be presented for steady-state and transient engine operation.
Imad A. Khalek, Southwest Research Institute
|| ORAL ONLY
|A Review of Current ODB Methods for Gasoline and Diesel Cars, Approaches for Fuel Systems, and Unmet Needs
John Van Gilder, General Motors Co.
|| ORAL ONLY
|Urea-SCR Injection: Meeting the Cold Start NOx Emissions Challenge
New rounds of stringent nitrogen oxides (NOx) emissions reduction regulations in Europe (Euro 6c) and North America (CARB LEV III, EPA Tier 3) are driving the optimization of existing diesel exhaust aftertreatment systems. Urea - Selective Catalytic Reduction (SCR) systems are among the de-NOx technologies that have been successfully introduced in recent years.
The new regulations are bringing a closer look to SCR de-NOx performance particularly during the cold start phase of the existing emissions certification cycles. This presentation will review some of the options under consideration to address cold start NOx emissions. Some of these approaches impose new and more severe requirements on the urea injection function – these are also reviewed as well as the response to these requirements by the injection system designers.
W. Nic Van Vuuren, Continental Automotive Systems