Kinetic Parameter Estimation of a Diesel Oxidation Catalyst under Actual Vehicle Operating Conditions

Growing interest has arisen to adopt Variable Valve Timing (VVT) technology for automotive engines due to the need to fulfill the pollutant emission regulations. Several VVT strategies, such as the exhaust re-opening and the late exhaust closing, can be used to achieve an increment in the after-treatment upstream temperature by increasing the residual gas amount. In this study, a one-dimensional gas dynamics engine model has been used to simulate several VVT strategies and develop a control system to actuate over the valves timing in order to increase diesel oxidation catalyst efficiency and reduce the exhaust pollutant emissions. A transient operating conditions comparison, taking the Worldwide Harmonized Light-Duty Vehicles Test Cycle (WLTC) as a reference, has been done by analyzing fuel economy, HC and CO pollutant emissions levels. The results conclude that the combination of an early exhaust and a late intake valve events leads to a 20% reduction in CO emissions with a fuel penalty of 6% over the low speed stage of the WLTC, during the warm-up of the oxidation catalyst. The same set-up is able to reduce HC emissions down to 16% and NOx emission by 13%.

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An on-board method to estimate the light-off temperature of diesel oxidation catalysts

International Journal of Engine Research ◽

10.1177/1468087418817965 ◽

2018 ◽

Vol 21 (8) ◽

pp. 1480-1492 ◽

Cited By ~ 1

Author(s):

Carlos Guardiola ◽

Benjamin Pla ◽

Pau Bares ◽

Javier Mora

Keyword(s):

Time Window ◽

Diesel Oxidation Catalyst ◽

Operating Conditions ◽

Oxidation Catalyst ◽

Temperature Estimation ◽

Exhaust Temperature ◽

Diesel Oxidation Catalysts ◽

Diesel Oxidation ◽

Exhaust Line ◽

Two Temperature

Current diesel engine regulations include on-board diagnostic requirements so that after-treatment systems need on-board methods to detect their aging state through the available measurements. In a state-of-the-art diesel exhaust line, two temperature and [Formula: see text] measurements can be found upstream and downstream of the diesel oxidation catalyst. Thus, the strategy presented in this article makes use of these measurements to estimate the light-off temperature, which has been widely studied as a characteristic of diesel oxidation catalyst aging. The light-off temperature estimation potential is evaluated first under dynamic engine operating conditions, in which [Formula: see text] measurements are proved to be precise enough to detect oxidation. However, dynamic conditions make the association of a representative temperature with an oxidation event difficult. Therefore, the method makes use of more controlled conditions at idle, during which the exhaust temperature decreases avoiding dynamics of normal driving conditions. During the idle, post-injection pulses are applied to determine whether oxidation occurs at a representative temperature measured by the upstream temperature sensor. The result of each pulse is used to generate a database. Then, after a long enough time window, the database generated will allow characterizing non-oxidation and oxidation temperatures, with an intermediate interval of indefinition. This article shows how the temperatures of these ranges increase as the light-off temperature increases, thereby validating the proposed method for light-off temperature estimation.

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The effect of biodiesel on activity of diesel oxidation catalyst and selective catalytic reduction catalysts in diesel engine

Renewable and Sustainable Energy Reviews ◽

10.1016/j.rser.2021.111286 ◽

2021 ◽

Vol 148 ◽

pp. 111286

Author(s):

Ibrahim Aslan Resitoglu

Keyword(s):

Diesel Engine ◽

Selective Catalytic Reduction ◽

Catalytic Reduction ◽

Diesel Oxidation Catalyst ◽

Oxidation Catalyst ◽

Diesel Oxidation ◽

Reduction Catalysts

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Development of a Low Emissions Upgrade Kit for EMD GP20D and GP15D Locomotives

ASME 2012 Internal Combustion Engine Division Fall Technical Conference ◽

10.1115/icef2012-92128 ◽

2012 ◽

Author(s):

Steven G. Fritz ◽

John C. Hedrick ◽

Tom Weidemann

Keyword(s):

Fuel Injection ◽

Diesel Oxidation Catalyst ◽

Oxidation Catalyst ◽

Particulate Filter ◽

Injection Timing ◽

Fuel Injection Timing ◽

Tier 1 ◽

Emission Regulations ◽

Diesel Oxidation ◽

Tier 3

This paper describes the development of a low emissions upgrade kit for EMD GP20D and GP15D locomotives. These locomotives were originally manufactured in 2001, and met EPA Tier 1 locomotive emission regulations. The 1,491 kW (2,000 HP) EMD GP20D locomotives are powered by Caterpillar 3516B engines, and the 1,119 kW (1,500 HP) EMD GP15D locomotives are powered by Caterpillar 3512B engines. CIT Rail owns a fleet of 50 of these locomotives that are approaching their mid-life before first overhaul. Baseline exhaust emissions testing was followed by a low emissions retrofit development focusing on fuel injection timing, crankcase ventilation filtration, and application of a diesel oxidation catalyst (DOC), and then later a diesel particulate filter (DPF). The result was a EPA Tier 0+ certification of the low emissions upgrade kit, with emission levels below EPA Line-Haul Tier 3 NOx, and Tier 4 HC, CO, and PM levels.

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