Road Traffic Junctions Modelling Case Study
Project: Assessment of modelling techniques for use at road traffic junctions
Client: Defra, Birmingham City Council, Coventry City Council, Leeds City Council, Leicester City Council, Sheffield City Council.
The Challenge
Air Quality Management requires the assessment of hot-spot areas where particular problems exist. These tend to be in inner-city areas and at complex road junctions where air flows are shielded due to the presence of buildings and pollutant levels can build-up.
The challenge posed to WSC was to determine the effectiveness of different modelling techniques to determine best-practice for assessing hot-spot areas.
The Solution
WSC worked in close co-operation with each of the participating City Councils to review the current methods used to assess air quality in pollution hotspots.
Using our expert knowledge of Air Quality Management practices, WSC developed state-of-the-art Computational Fluid Dynamics models of pollution hot-spots in each of the urban locations. These models were tested against the current tools used by each of the local Authorities.
An analysis was also undertaken of how simple improvements to the input data used for these models affected the accuracy of the predictions.
The results showed that, whilst in some circumstances the more complex CFD modelling yielded better results, on the whole effort would be better spent using the current tools that the councils had available and improving the realism of the input data used, especially the accuracy of road traffic data.
CFD Model (Red Shows Hot Spot)
Current Model
The Benefits
- The results of the study have enabled councils to determine actions that would result in tangible improvements to how they conduct regulatory modelling assessments.
- This has enabled air quality professionals to focus on areas where real improvements can be made without having the significant increases in costs and time that would be required by having to conduct highly detailed assessments at all hotspot locations.
- The results of the study will be used to assist the development of future governmental environment policies and to provide guidance to local authorities on their implementation.