Tenneco Inc.

Diesel Aftertreatment Predictive Development Process

Meeting increasingly stringent emission control regulations poses significant technical challenges to manufacturers of Diesel aftertreatment systems. EPA's standards for 2007 required a 90% reduction in particulate matter, and in the coming years emission standards for both particulates and oxides of nitrogen will be reduced still further.

In the light duty truck market, the new regulations have tripled the weight of the average exhaust system compared to previous model years, due to increased size and complexity. In addition, traditional methods of exhaust system design required multiple iterations, while identification of performance failures occurred late in the process. That meant costly delays in vehicle development. Tenneco has changed the rules of the game through their successful development and application of proprietary "light tools" for use in design of Diesel aftertreatment emission controls systems.

Tenneco directed advanced engineering efforts toward meeting the 2007 Diesel emissions regulations in the United States, with the intention of expanding market share. They understood that the complexity of exhaust system design dictated an interdisciplinary approach to modeling and understanding system performance. They developed analytical tools based on fluid dynamics, heat transfer, solid mechanics, and system dynamics and vibrations. Models are continuously improved by the addition of new experimental and field data. These innovative predictive tools allow design engineers to assess the effects of design parameters on exhaust system performance. This innovation requires only a fraction of the time and training it takes to learn and use more complex commercially-available CAD/CAE software packages. Tenneco's proprietary tools insure cost-effective manufacture and eliminate costly engineering re-work cycles, as well as allowing quick and accurate response to rapidly changing customer demands.

Tenneco's "light tools" have allowed their customers to meet stringent emissions requirements on a timely basis. This innovation is directly responsible for Tenneco's capture of 100% of the 2007 light duty Diesel truck aftertreatment share. It has raised the standard of excellence in Diesel exhaust system design.