Jens Chr. Bennetsen

Head of Center of Excellence for Advanced Simulations

T: +45 5161 6475

Can you use 3D technology to plan a city? With temperatures reaching 50 degrees in the summer, low humidity, intense solar radiation, and strong dusty winds, Saudi Arabia’s capital Riyadh is the not the easiest place to create liveable city spaces. 

Nevertheless, that was the end-goal of a new development project, called King Abdullah Financial District (KAFD), set in the Asahafa area of Riyadh and comprising both financial institutions, residential buildings and recreational areas. 

Together with Henning Larsen, Ramboll planned the urban design for the area. A vital part of making the area attractive was to reduce air pollution and heat. Here, computer-based 3D technology came in handy. 

By using Computational Fluid Dynamics (CFD) early in the planning process, we could digitally test the planned design and use the insights to ensure that the real-life district had clean air and was (relatively) cool. 

Cleaner air and temperature reductions of 8 degrees Celsius 

CFD provides you with precise data about the design performance and enables insights that can save a lot of time and money in the end. 

When we were developing the Kind Abdullah Financial District, CFD technology was used to simulate and visualise the wind flow and heat exposure throughout the planned district, to see how life on the streets between the buildings would be affected. 

The simulation process took city geometry, vegetation plans and hourly meteorology data into account. The output was hourly surface and near surface temperature maps. 

“The computational capacity that is available nowadays makes it possible to calculate local microclimates with CFD, inside the urban city. Relative wind speeds can be visualised, and the probability of the wind speeds exceeding certain values can be calculated to evaluate the wind comfort for various pedestrian activities”, Jens Christian Bennetsen, Head of Ramboll’s Centre of Excellence for Advanced Simulations, explains.

Based on these insights, the urban design could be revised to improve the urban climate. Building proportions and façade materials were changed and the design was optimized with strategic use of vegetation and water features – all to bring down the temperatures and work against the strong winds and pollution rates. 

And it worked! The outdoor temperature was reduced with up to 8 degrees Celsius and the design provided much cleaner air in the district centre.