A new approach for static NOx measurement in PTI

Fernández E. ; Valero A. (Universidad de Zaragoza) ; Alba J.J. (Universidad de Zaragoza) ; Ortego A. (Universidad de Zaragoza)

Resumen: NOx emissions in vehicles are currently only controlled through the homologation process. There is a lack of knowledge to assess and control real NOx emissions of vehicles reliably. Even if vehicles in EU-27 are subject to Periodical Technical Inspection (PTI), NOx are not among the pollutants currently being controlled. For PTIs, tests need to be simple, quick, inexpensive, representative, and accurate. Ideally, tests need to be carried out under static conditions, without the need for a power bench or complex equipment. In this paper, a new approach for measuring NOx in PTI is proposed. The method has been developed and validated at a PTI Spanish station to ensure feasibility and repeatability. This method is based on the relationship between the “% engine load” value and exhaust NOx concentration at idle engine speed. Starting from the state of minimum possible power demand in a vehicle (idling and without any consumption), a load state with an average 98% increase in engine power demand is generated by connecting elements of the vehicle’s equipment. The relationship between power demand (through the “% engine load” value) and NOx concentration is then analyzed. The quality and representativity of this relationship have been checked with a p-value lower than 0.01. The method has been compared with a different NOx measurement technique, based on the simulation on a test bench and the ASM 2050 cycle, showing better performance in terms of repeatability and representativeness. The “% engine load” dispersion with the new approach is 7%, which ensures the reliability and repeatability of the method. The results show that the proposed method could be a valuable tool in PTI to detect high NOx emitting vehicles and to obtain information from the diesel vehicles fleet. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Idioma: Inglés

DOI: 10.3390/su132313424

Año: 2021

Publicado en: Sustainability (Switzerland) 13, 23 (2021), 13424 [34 pp]
ISSN: 2071-1050

Factor impacto JCR: 3.889 (2021)

Categ. JCR: ENVIRONMENTAL STUDIES rank: 57 / 128 = 0.445 (2021) - Q2 - T2
Categ. JCR: ENVIRONMENTAL SCIENCES rank: 133 / 279 = 0.477 (2021) - Q2 - T2
Categ. JCR: GREEN & SUSTAINABLE SCIENCE & TECHNOLOGY rank: 35 / 47 = 0.745 (2021) - Q3 - T3
Categ. JCR: GREEN & SUSTAINABLE SCIENCE & TECHNOLOGY rank: 7 / 9 = 0.778 (2021) - Q4 - T3

Factor impacto CITESCORE: 5.0 - Social Sciences (Q1) - Engineering (Q1) - Energy (Q2) - Environmental Science (Q1)

Factor impacto SCIMAGO: 0.664 - Energy Engineering and Power Technology (Q1) - Renewable Energy, Sustainability and the Environment (Q1) - Management, Monitoring, Policy and Law (Q1) - Geography, Planning and Development (Q1)

Tipo y forma: Article (Published version)

Área (Departamento): Área Ingen.e Infraestr.Transp. (Dpto. Ingeniería Mecánica)
Área (Departamento): Área Máquinas y Motores Térmi. (Dpto. Ingeniería Mecánica)