Computational evaluation of wind comfort at the deck of a large football stadium in an urban environment with the new Dutch wind nuisance standard

3D steady-state RANS CFD simulations are used in combination with the new Dutch wind nuisance standard to assess the pedestrian wind comfort at the deck of a large football stadium in downtown Amsterdam, before and after the addition of new high-rise buildings. The simulated mean wind speed is compared with full-scale measurements. An essential aspect is the tuning of the simulations to the measurements by changing the physical roughness height kS of the local terrain in the simulations, which is one of the parameters that generate the largest uncertainty for the calculated wind speed. The tuning procedure ensures that appropriate kS values are used and that appropriate wind speed values are obtained as input for the wind comfort study. The application of the wind nuisance standard indicates that wind comfort at the most critical positions at the Deck is moderate for traversing and poor for strolling, both in the new and the future situation. The addition of the new high-rise buildings has only a limited effect. Finally, the results obtained by the Dutch wind nuisance standard are compared to those obtained with a more traditional approach for the transformation of wind statistics, as used in earlier studies. It is shown that large to very large differences occur, that can significantly change the outcome of wind comfort studies and can lead to wrong decisions.