Présentation
Dans le domaine de l'ingénierie éolienne, une modélisation et une validation précises sont essentielles pour garantir l'intégrité structurale et les performances aérodynamiques de diverses structures telles que les antennes (Figure 1). Due to their slender and often flexible nature, antennas are particularly susceptible to wind-induced forces, such as vortex shedding, galloping, and buffeting. These dynamic effects can lead to significant structural vibrations, material fatigue, and even failure if not properly accounted for in the design phase.
To address these challenges, rigorous validation of computational models is necessary to ensure that the theoretical predictions align with the real-world performance. One such example is the validation of antenna wind-loading simulations through experimental testing and computational fluid dynamics (CFD) analysis. This process allows engineers to refine their models, improve accuracy, and enhance the overall reliability of antenna structures in various environmental conditions.
In collaboration with RWTH Aachen University, a leading institution in engineering and applied sciences, practical studies are conducted on antenna structures exposed to wind loads. By combining theoretical approaches with empirical data, the research aims to bridge the gap between simulation and reality, contributing to the development of safer, more resilient antenna designs. This study underscores the importance of validation in wind engineering, demonstrating how academic-industry collaboration can lead to more precise modeling techniques and improved structural performance in real-world applications.
Description du projet
In the current validation example, the force coefficient for both CFD simulation in RWIND and experimental study [1] from RWTH Aachen University is investigated. The central model represents an antenna with a rectangular cross-section, positioned above a grid surface that serves as the ground plane or wind tunnel floor. The model includes several dimensional labels in magenta, indicating specific measurements: the total height of the antenna is 0.50 m; its base is elevated 0.20 m from the ground, with 0.08 m as the length in the y direction; and the top width (in the x direction) of the antenna is 0.056 meters (image 2).
Analytical Solution and Results
The required assumption of the wind simulation is illustrated as the following table:
| Tableau 1 : Rapport dimensionnels et données d’entrée | |||
| Vitesse de référence du vent | V | 10 | m/s |
| Crosswind Dimension | b | 0.080 | m |
| Alongwind Dimension | d | 0.058 | m |
| Hauteur | href | 0,5 | m |
| Bottom Gap | Écart | 0,20 | m |
| Densité de l’air - RWIND | ρ | 1,25 | kg/m3 |
| Directions du vent | θVent | 0o to 360o with step 30o | Degré |
| Modèle de turbulence - RWIND | Steady RANS k-ω SST | - | - |
| Viscosité cinématique (équation 7.15, EN 1991-1-4) - RWIND | ν | 1,5*10-5 | m2/s |
| Ordre du schéma - RWIND | Deuxième | - | - |
| Valeur résiduelle visée - RWIND | 10-4 | - | - |
| Type résiduel - RWIND | Pression | - | - |
| Nombre minimal d'itérations - RWIND | 800 | - | - |
| Couche limite - RWIND | NL | 10 | - |
| Type de fonction de voile - RWIND | Amélioré / combiné | - | - |
| Intensité de la turbulence | I | 3% | - |
The wind force coefficients for various wind directions (θ = 0o to 360o with step of 30o) have been determined using RWIND, as illustrated in Image 3. The results indicate a deviation of approximately 8% from the experimental data.
Furthermore, the Antenna model is available to download here:
