Low Ambient Temperature Impact on a Low NOX Demonstration System

被引：0

作者：

Zavala B. ^{[1
]}

Sharp C. ^{[1
]}

机构：

[1] Southwest Research Institute, United States

来源：

SAE International Journal of Advances and Current Practices in Mobility | 2023年 / 6卷 / 01期

关键词：

Compendex;

D O I：

10.4271/2023-01-0361

中图分类号：

学科分类号：

摘要：

In 2020, CARB adopted the low NOX omnibus ruling, which provided revisions to on-road heavy duty engine compliance standards and certification practices. As part of the updates to the regulation, CARB has introduced a new in-use vehicle testing process that broadens the operation modes tested and considers the manufacturer's intended vehicle application. Compared to the previous method, or the Not-to-Exceed approach, cold start and low ambient temperature provisions were included as part of the updates. The inclusion of low temperature operation requires the OEMs to design a robust engine and aftertreatment package that extends NOX conversion performance. The following work discusses the NOX emissions performance impact in a low temperature ambient environment. The engine and aftertreatment system evaluated was designed to comply with CARB's low NOX regulations. The cycles tested included the CARB Southern NTE cycle and an FTP-LLC protocol. Both test sequences were intended to replicate drive cycles observed in the field. Overall, results indicated higher emissions for the low ambient temperature conditions. Utilizing the 3-bin moving average window method, emissions results were calculated for idle, low load, and medium / high load bins. While the CARB Southern NTE cycle showed an increase in the idle and low load bins, the system was able to maintain compliance. The medium / high load bin, however, exceeded the compliance limit by ~40% due to changes in the exhaust conditions. For the FTP-LLC protocol, LLC segments also increased, but maintained compliance based on the 2031+ in-use NOX standards. Furthermore, low ambient temperature operation creates challenges for controlling emissions even with a low NOX system. © 2023 SAE International. All rights reserved.

引用

共 20 条

[11] Sharp C., Neely G., Zavala B., Rao S., CARB Low NO<sub>X</sub> Stage 3 Program - Final Results and Summary, SAE Int. J. Adv. & Curr. Prac. in Mobility, 3, 4, pp. 1508-1525, (2021)
[12] Neely G., Sharp C., Pieczko M., McCarthy J., Simultaneous NOX and CO<sub>2</sub> Reduction for Meeting Future California Air Resources Board Standards Using a Heavy-Duty Diesel Cylinder Deactivation-NVH Strategy, SAE Int. J. Engines, 13, 2, pp. 191-210, (2020)
[13] Neely G., Sharp C., Rao S., CARB Low NOx Stage 3 Program - Modified Engine Calibration and Hardware Evaluations, SAE Technical Paper 2020-01-0318, (2020)
[14] Zavala B., Sharp C., Neely G., Rao S., CARB Low NOX Stage 3 Program - Aftertreatment Evaluation and Down Selection, SAE Technical Paper 2020-01-1402, (2020)
[15] Rao S., Sarlashkar J., Rengarajan S., Sharp C., Et al., A Controls Overview on Achieving Ultra-Low NOx, SAE Technical Paper 2020-01-1404, (2020)
[16] Electronic Code of Federal Regulations (eCFR), Office of Federal Register, (2019)
[17] Eakle S., Zavala B., Sharp C., The DAAAC Protocol: A Procedure for Developing Accelerated Aging Cycles for Diesel Aftertreatment, SAE Technical Paper 2022-01-1017, (2022)
[18] Zavala B., Eakle S., Sharp C., DAAAC Protocol for Durability Demonstration of Diesel Aftertreatment Systems: Emissions Performance Validation, SAE Technical Paper 2022-01-1015, (2022)
[19] Final Statement of Reasons for Rulemaking Including Summary of Comments and Agency Responses: Amendments to the Exhaust Emissions Standards and Test Procedures for 2024 and Subsequent Model Year Heavy-Duty Engines and Vehicles, Heavy-Duty On-Board Diagnostic System Requirements, Heavy-Duty In-Use Testing Program, Emissions Warranty Period and Useful Life Requirements, Emissions Warranty Information, and Reporting Requirements, and Corrective Action Procedures, In-Use Emissions Data Reporting Re
[20] (2020)

← 1 2 →