Large-Eddy Simulation (LES) on the Square and Triangular Tall Buildings to Measure Drag Force

Abstract

The wind load issues play a significant role in designing tall buildings, which has sometimes been considered an even more essential factor than earthquake loads. Also, investigating wind behavior in tall buildings is a crucial issue in architectural and structural design. A primary concern of wind engineering and aerodynamics is drag force. Drag force refers to a solid object’s behavior in the relative wind flow velocity direction in terms of fluid dynamics. The investigation involved only drag forces. The Autodesk Flow Design 2014 software was utilized as a wind tunnel simulator. The Large Eddy Simulation (LES) method was used for turbulence solving. This study aims to optimize tall square and triangular-shaped buildings in order to reduce drag force under along-wind motion. For this purpose, architectural aerodynamic strategies such as chamfered, rounded, and recessed corners were applied as aerodynamic modifications. Moreover, aerodynamic forms, including tapering and setting back on shapes, were applied on 24 building models. Generally, the height (H) and breadth (b) ratios were set to H: 200 m, which is equivalent to almost 60 stories, and b: 25 m wide. The obtained results indicate that model S5 (with a square floor plan) achieved 0.65 CD, and the t1 (with a triangular floor plan) achieved 0.30 CD, which could provide the best building model to reduce drag force. In this regard, the s1 could perform over 50% better in reducing wind load. Concerning the aerodynamic modification performance, the simulation results indicate that these modifications were able to lead to over 50% better performance in reducing wind force in square samples compared to triangular samples.

Shape optimization of a corner‐recessed square tall building to reduce mean wind pressure using a multi‐objective genetic algorithm

“…They also evaluated the area‐averaging amplification factor for different wind speed conditions and compared it for different cases. Daemei et al 8 carried out an optimized study of tall square and triangular‐shaped buildings to reduce drag force under the along‐wind direction using LES as the turbulence model. Different aerodynamic approaches like corner tapering, corner set‐backing, corner chamfering, corner rounding, corner recessing, and so on, have been applied as aerodynamic modifications on 24 building models.…”

Large-eddy simulation of airflow dynamics around a cluster of buildings

“…In this paper, a comparison of the optimal model’s aerodynamic responses to the basic triangle model revealed that the moment coefficient was lowered by 56%. To reduce the drag force during along-wind motion, Daemei et al 38 used the LES model to optimize the triangular-shaped and tall square buildings. For the high-rise skyscrapers, the mean velocities, turbulent kinetic energies, tracer concentrations, and Reynolds stresses were recently studied using adaptive LES by Aristodemou et al 39 to discover how they affect the local environment.…”

Aerodynamic Modification of High-Rise Buildings by the Adjoint Method

“…Additionally, numerical methods have offered valuable insights into aerodynamic forces; for example, Li et al's research investigated the impact of various taper ratios on wind load reduction in tall rectangular buildings [29], underscoring that increasing the taper ratio enhances the aerodynamic efficiency of rectangular high-rise structures and supplies pivotal data to the wind-resistant design of such buildings [30]. Daemei et al employed large eddy simulation (LES) to assess drag forces on different buildings [31], while Meena et al compared various models, including Y-shaped models with rounded corners, to evaluate their responses to severe winds [32]. In recent years, the use of computational fluid dynamics and numerical simulations have experienced significant growth in the field of tall building aerodynamics, with each developing a unique focus [33][34][35].…”