Storm Analysis for Langwies Viaduct

Based on wind measurements, wind hazards can be assessed for their locations. However, wind measurements have the disadvantage of limited spatial representativeness. This is where models can step in.

The turbulence model PALM makes it possible to simulate the flow around the Langwies Viaduct with very high spatial resolution. Using both static and dynamic input data, the wind conditions during storm “Eberhard” were calculated and validated using wind measurements taken on the bridge. The following graphic shows a result of the wind modeling.

Cross-section of the flow field at the time of the strongest calculated gust. The location of the measurement station is marked with a circle.

The model results correspond very well with the measured gusts and 10-minute means. This means that wind hazards along the railway section can be quantified using the model.

Meteotest uses the PALM model not only for simulating airflow conditions. With PALM-4U, it is also possible to model urban climate phenomena such as heat islands during heatwaves (links only available in German):

• Wirksamkeitsanalyse verschiedener Massnahmen zur Reduktion der Hitzeentwicklung

• Modellierung der humanbioklimatischen Bedingungen für sommerliche Hitzesituationen in Ostschweizer Kantonen und Städten