Modelling and experimental validation of deposition on vegetation to facilitate urban particulate matter mitigation. 01/01/2019 - 31/12/2022

Abstract

The adverse health effects resulting from exposure to air pollution, such as particulate matter (PM), are becoming more and more prominent. Although emissions are reducing, too high PM concentrations are still expected at locations with high traffic volumes and in so-called street canyons. Urban green has been considered as a potential urban planning solution for improving air quality, especially green walls have a great potential. Vegetation has an influence on air flow patterns and aids in the removal of particulate pollutants from the atmosphere by dry deposition on the leaf surfaces. Both field, wind tunnel and modelling studies (especially CFD) have been complementary used to investigate these effects, however, current deposition models are not able to grasp all mechanisms responsible for deposition and resuspension. This research proposal will address this shortcoming by developing a size-resolved deposition model considering all relevant mechanisms as well as resuspension on plant leaves. The relevant aerodynamic parameters and deposition/resuspension rate of different plant leaf orientations of green wall species will be determined with wind tunnel experiments. These results will serve as input of a model framework at real scale. The model framework will be applied to explore the potential of nature-based systems and eco-technological solutions for urban PM mitigation. This research proposal is very innovative and challenging since it transcends the state of the art.

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Project type(s)

  • Research Project

PM removal by urban green: a scientific modelling framework. 01/10/2017 - 31/12/2018

Abstract

In this project a scientific framework for assessing the particulate matter (PM) removal of urban green is developed. We aim at enhancing the insight in the several phenomena that occur at the level of plant surfaces in the presence of PM polluted air, and in the way meteorological, physiological and morphological (plant) parameters affect PM transport, deposition and resuspension. The methodology is based on (1) predictive computational models for air flow, PM transport and PM deposition / resuspension on plant surfaces and (2) experimental analysis of the aerodynamics of urban green and PM deposition on their surfaces. By combining the sophisticated modularity in modeling techniques with experimental procedures, insight will be gained into the relevant underlying dynamic processes involved (PM transport, deposition and resuspension) and the effects of meteorological and physiological / morphological parameters. Based on the framework, we will explore and test the potential of 'eco-technological solutions' for the mitigation of urban air pollution, in particular of PM pollution. Conventional "passive" application of urban green does not fully use its deposition potential. In this project, innovative ways of using urban green in the smart planning of urban adaptation are suggested and studied. Additional benefits might be found in such engineered green systems for both the building and green industry and the environment, but a great deal of knowledge is still lacking to optimally develop and implement them. The knowledge build up in this research project will be very useful in the global framework of designing healthy, sustainable cities. Furthermore, the results will be very helpful to develop and tailor innovative eco-technological solutions, based on a solid scientific background, which adheres to all requirements and regulations.

Researcher(s)

Research team(s)

Project type(s)

  • Research Project