Evaluation of the NO2 burden within a joint street canyon and tunnel portal micro environment

Ulrich Uhrner, Raphael Jakob Reifeltshammer, Peter-Johann Sturm

Research output: Contribution to journalArticlepeer-review


Substantial breaches in NO2 limits in the vicinity of a tunnel portal
and street canyon micro environment provided the motivation for this paper.
The impact of portal and surface road emissions was assessed and mitigation
scenarios computed, in order to aid the authorities responsible. Emphasis was
placed on detailed emission processing. A unique data set from nine NO2
monitors located near the portal and within the street canyon was used to
evaluate the model approach using a Lagrangian particle model. Good
agreement with measurements was obtained using simple NOx/NO2 conversion
approaches. The NOx/NO2 concentration pattern is dominated by surface road
emissions. A kerbside area of ~30 m in the driving direction is clearly
dominated by the portal emissions indicating effective diffusion at the portal.
Major uncertainties are related to the interaction of flow and turbulent mixing
from ambient atmospheric conditions and traffic, particularly at low wind speed
Original languageEnglish
JournalInternational journal of environment and pollution
Issue numberVol. 65 Nos. 1/2/3
Publication statusPublished - 15 Aug 2019

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