Abstract
Abstract
Diesel-fueled passenger cars offer both good engine torque, as well as the potential for reduced greenhouse gas emissions compared to gasoline-fueled vehicles. One issue facing diesel powertrains, however, is continuing to meet increasingly stringent emissions standards throughout the world. Delphi is developing an advanced reformer-based emissions control solution focused on high efficiency NOx reduction and improved particulate filter regeneration. This system offers an attractive alternative to urea SCR. The approach generates hydrogen-rich reformate on demand to regenerate a Lean NOx Trap (LNT). The diesel fuel reformer system eliminates the need for a urea distribution infrastructure, while offering LNT regeneration without post injection and with reduced dependence on precious metals. For increased emission system robustness, the diesel fuel reformer lowers the temperature requirements for LNT desulfation and provides improved DPF regeneration control.
In the sections that follow, we begin with a brief description of reforming fundamentals, including an overview of the operating characteristics and performance of a representative diesel fuel reformer. The paper then outlines the integration of a prototype on-board diesel reformer system onto a demonstration vehicle. The bulk of the paper is devoted to emissions test results that demonstrates the low emissions capability of this vehicle. Finally, we describe early results for reformate-based particulate filter regeneration.