Optimum Design of Dome Structures Modeled with Bezier Curves Considering Wind Load Effects by Computational Fluid Dynamics

Abstract

Dome structures belong to the category of space structures capable of covering large areas without internal columns. Due to their lightweight nature, the wind loads typically have a greater influence on their design than earthquake loads. In this study, external wind load coefficients are evaluated by computational fluid dynamics (CFD). Given the limitations of wind codes and the impracticality of conducting experimental tests for every structure, numerical simulation provides a reliable alternative for assessing wind load effects. In this study, six Reynolds-averaged Navier-Stokes (RANS) turbulence models, including standard k - ε , re-normalization group (RNG), realizable, standard k - ω , baseline (BSL), and shear stress transport (SST), are evaluated and validated against experimental investigations in the literature to identify the model with the highest prediction accuracy. The findings indicate that the k - ω BSL model achieves the best agreement and is thus selected for subsequent analyses. The primary objective of this research is the aerodynamic shape and sizing optimization of the domes. To achieve the optimal dome geometries for wind load mitigation, some basic configurations are generated by cubic Bezier polynomials. The weight of the structure is considered as the objective function for sizing optimization, aiming to minimize it while satisfying design constraints. In this paper, sequential linear programming (SLP) and momentum methods are applied for sizing optimization. Numerical results indicate that thin and short domes yield more optimal designs in terms of structural weight, when subjected to dead, snow, and wind loads. It is noteworthy that these findings result from the simultaneous changes in the two variables, wind force and structural configuration. The integration of CFD-based aerodynamic analysis with structural optimization using Bezier-defined shapes presents a novel framework for the efficient and lightweight design of domes.