Browse Publications Technical Papers 2018-01-1136
2018-04-03

Achieving Fast Catalyst Light-Off from a Heavy-Duty Stoichiometric Natural Gas Engine Capable of 0.02 g/bhp-hr NO X Emissions 2018-01-1136

Recently conducted work has been funded by the California Air Resources Board (CARB) to explore the feasibility of achieving 0.02 g/bhp-hr NOX emissions for heavy-duty on-road engines. In addition to NOX emissions, greenhouse gas (GHG), CO2 and methane emissions regulations from heavy-duty engines are also becoming more stringent. To achieve low cold-start NOX and methane emissions, the exhaust aftertreatment must be brought up to temperature quickly while keeping proper air-fuel ratio control; however, a balance between catalyst light-off and fuel penalty must be addressed to meet future CO2 emissions regulations. This paper details the work executed to improve catalyst light-off for a natural gas engine with a close-coupled and an underfloor three-way-catalyst while meeting an FTP NOX emission target of 0.02 g/bhp-hr and minimizing any fuel penalty. Two methods for achieving fast catalyst light-off were examined: 1) secondary air injection upstream of the front face of the close-coupled catalyst, and 2) operating half of the cylinders rich and the other half of the cylinders lean. Results from this study demonstrate a potential pathway to achieving ultra-low NOX emissions and future GHG Phase 2 standards on heavy-duty vehicles.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.

Due to current capacity constraints, printed versions of our publications - including standards, technical papers, EDGE Reports, scholarly journal articles, books, and paint chips - may experience shipping delays of up to four to six weeks. We apologize for any inconvenience.
We also recommend:
TECHNICAL PAPER

Performance of a Half-Heusler Thermoelectric Generator for Automotive Application

2018-01-0054

View Details

TECHNICAL PAPER

Methane Dedicated Catalysts for Heavy-Duty Natural Gas Engines

961087

View Details

TECHNICAL PAPER

Catalyst Development for Stoichiometric and Lean Bum Natural Gas Engines

942419

View Details

X