IRLAM-An Advanced Technology for NOx Measurement from Diluted Exhaust of a Light Duty Vehicle (LDV) Horiba Instruments Incorporated

Format:

Book

Conference/Event

Author/Creator:

Rahman, Montajir, author.

Contributor:

Hara, Kenji

Israel, Joshua

Nagura, Naoki

Nevius, Tim

Conference Name:

SAE Energy and Propulsion Conference (2025-10-14 : Ypsilanti, Michigan, United States)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2025

Summary:

The United States Environmental Protection Agency (US-EPA) requires nitrogen oxides (NOx) measurement using Chemiluminescent Detectors (CLDs), Non-dispersive Ultraviolet (NDUV), and Zirconia Oxide (ZrO2) analyzers, as outlined in the 40 CFR Part 1065. Quantification of NO2 by CLD requires dual-CLDs; one dedicated to measuring the NO and another coupled with a NO2-to-NO converter to measure the total NOx. Measurement by using dual-CLDs involves mathematically subtracting NO from total NOx to get NO2 information. This requires perfect time alignments of both CLDs assigned for measuring NO and NOx to maintain accurate NO2 calculations. The NO2-to-NO converters can degrade over time and need to be replaced to get accurate total NOx measurement.In this study, Infra-red Laser Absorption Modulation (IRLAMTM) technology, which is an advanced QCL-IR spectroscopy proposed in the previous study [1], is used to measure NO and NO2 simultaneously in the exhaust gas of light-duty vehicles. This approach offers several advantages such as direct measurement of both NO and NO2 without a NO2-to-NO converter. The primary objective of this study is to compare IRLAM technology with conventional CLD by collecting a statistically significant set of certification-quality NOx emissions data in compliance with the requirements of 40 CFR 1065 from diluted exhaust of a MY2024 SULEV light-duty vehicles during certification testing.The results demonstrate no statistically significant difference between the measurements obtained from the two methodologies, establishing IRLAM as a suitable candidate for an alternate procedure for NOx measurement during certification testing. The t-values for all duty cycle populations were consistently below the critical t-values at both 90% and 95% confidence intervals. The f-test values for all duty cycle populations were consistently lower than the critical f-values at both 90% and 95% confidence intervals

Notes:

Vendor supplied data

Publisher Number:

2025-01-0403

Access Restriction:

Restricted for use by site license