Computational modelling of pollution dispersion in the near wake of a vehicle

The feasibility of using CFD to model the dispersion of pollutant in the near wake of a model vehicle was investigated through a series of experimental and computational studies. The near wake structure of the MIRA 33% scale reference vehicle (fastback) was measured using Particle Image Velocimetry...

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Main Author: Richards, Kathryn
Format: Thesis (University of Nottingham only)
Language:English
Published: 2003
Subjects:
Online Access:https://eprints.nottingham.ac.uk/10108/
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author Richards, Kathryn
author_facet Richards, Kathryn
author_sort Richards, Kathryn
building Nottingham Research Data Repository
collection Online Access
description The feasibility of using CFD to model the dispersion of pollutant in the near wake of a model vehicle was investigated through a series of experimental and computational studies. The near wake structure of the MIRA 33% scale reference vehicle (fastback) was measured using Particle Image Velocimetry (PIV), and hotwire anemometry and the dispersion of a tracer measured using Flame Ionisation Detectors (FIDs). The experimental data not only provided insight into the dispersion character of the model vehicles's near wake but more importantly produced data for the validation of the numerical simulations of the measured near wake and dispersion fields. The numerical simulations of the near wake flow field were conducted using the CFD code STAR-CD with the standard, RNG, Chen and nonlinear (quadratic) k- e models in combination with Upwind (UD), Linear Upwind (LUD) and the Monotone Advection and Reconstruction (MARS) differencing schemes. Validation showed the predicted flow field to be in good agreement with the measured flow field. Using the numerical flow field predictions as a foundation the dispersion of a passive gaseous pollutant was simulated by modelling the dispersion of scalar quantity released into the computational domain using a fluid injection technique. The numerical predictions of both mean velocity and concentration fields were validated against the experimental data using various statistical validation techniques. Several short investigations into the influence of vehicle speed and exhaust mass flow rate were also conducted to further assess the applicability and use of the technique in investigating dispersion in the near wake of a vehicle. Relative successes in both the velocity field and dispersion simulations were demonstrated in making predictions of the mean velocity and concentration fields. However there is clearly the need for more development and in particular the application of time-dependent techniques for the underlying velocity solutions in order that peaks in mean concentration resulting from build-up due to unsteadiness in the flow field are fully captured. Nevertheless the study demonstrated the potential for the use of STAR-CD to investigate and understand in more detail the dispersion of pollution close behind a road vehicle and possibly assess the concentration levels, at the road side of different pollutants released.
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format Thesis (University of Nottingham only)
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institution University of Nottingham Malaysia Campus
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language English
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spelling nottingham-101082025-02-28T11:07:09Z https://eprints.nottingham.ac.uk/10108/ Computational modelling of pollution dispersion in the near wake of a vehicle Richards, Kathryn The feasibility of using CFD to model the dispersion of pollutant in the near wake of a model vehicle was investigated through a series of experimental and computational studies. The near wake structure of the MIRA 33% scale reference vehicle (fastback) was measured using Particle Image Velocimetry (PIV), and hotwire anemometry and the dispersion of a tracer measured using Flame Ionisation Detectors (FIDs). The experimental data not only provided insight into the dispersion character of the model vehicles's near wake but more importantly produced data for the validation of the numerical simulations of the measured near wake and dispersion fields. The numerical simulations of the near wake flow field were conducted using the CFD code STAR-CD with the standard, RNG, Chen and nonlinear (quadratic) k- e models in combination with Upwind (UD), Linear Upwind (LUD) and the Monotone Advection and Reconstruction (MARS) differencing schemes. Validation showed the predicted flow field to be in good agreement with the measured flow field. Using the numerical flow field predictions as a foundation the dispersion of a passive gaseous pollutant was simulated by modelling the dispersion of scalar quantity released into the computational domain using a fluid injection technique. The numerical predictions of both mean velocity and concentration fields were validated against the experimental data using various statistical validation techniques. Several short investigations into the influence of vehicle speed and exhaust mass flow rate were also conducted to further assess the applicability and use of the technique in investigating dispersion in the near wake of a vehicle. Relative successes in both the velocity field and dispersion simulations were demonstrated in making predictions of the mean velocity and concentration fields. However there is clearly the need for more development and in particular the application of time-dependent techniques for the underlying velocity solutions in order that peaks in mean concentration resulting from build-up due to unsteadiness in the flow field are fully captured. Nevertheless the study demonstrated the potential for the use of STAR-CD to investigate and understand in more detail the dispersion of pollution close behind a road vehicle and possibly assess the concentration levels, at the road side of different pollutants released. 2003 Thesis (University of Nottingham only) NonPeerReviewed application/pdf en arr https://eprints.nottingham.ac.uk/10108/1/KAR_Thesis.pdf Richards, Kathryn (2003) Computational modelling of pollution dispersion in the near wake of a vehicle. PhD thesis, University of Nottingham. pollution dispersion computational fluid dynamics CFD car modelling
spellingShingle pollution dispersion computational fluid dynamics CFD car modelling
Richards, Kathryn
Computational modelling of pollution dispersion in the near wake of a vehicle
title Computational modelling of pollution dispersion in the near wake of a vehicle
title_full Computational modelling of pollution dispersion in the near wake of a vehicle
title_fullStr Computational modelling of pollution dispersion in the near wake of a vehicle
title_full_unstemmed Computational modelling of pollution dispersion in the near wake of a vehicle
title_short Computational modelling of pollution dispersion in the near wake of a vehicle
title_sort computational modelling of pollution dispersion in the near wake of a vehicle
topic pollution dispersion computational fluid dynamics CFD car modelling
url https://eprints.nottingham.ac.uk/10108/