Numerical Simulation and Optimization of Wind Effects of Porous Parapets on Low‐Rise Buildings with Flat Roofs

Abstract

This paper presents a procedure to optimize the porosity of parapets to improve the aerodynamic behavior of low-rise buildings with flat roofs, by coupling an optimization algorithm and computational fluid dynamics (CFD) simulations. The performance of solid parapets to decrease the wind suctions on flat roofs induced by conical vortices was firstly studied, based on four turbulence closure models (standard k-ε, RNG k-ε, SST k-ω, and RSM). The simulation results were validated by comparing with the wind tunnel data. Additionally, the porous parapet was treated as a momentum sink in the governing momentum equation, and the RSM turbulence model was employed. As a result, six optimization studies focusing on the highest mean suction minimization that consider parapet height were presented. The aim of this paper is to search for the best performing porosity through an automatic CFD-based optimization methodology. At low relative heights (hp/H = 0.01∼0.05, hp is the parapet height, and H is the roof height), the porous parapet with optimal porosity in between 38.2% and 52.3% seems to be more effective than solid parapets in attenuating high corner suctions generated by conical vortices; however, the solid parapet gives the best performance in the reduction of wind suctions when hp/H ≥ 0.07.

A Data-Driven Approach to Improve the Operation and Maintenance Management of Large Public Buildings

“…Therefore, the discrete frequencies were divided into 4 intervals as shown in TABLE 6. The table indicates that the number of facilities with frequencies that are no greater than 30 is 54, accounting for 36.5% of the total number (148), but the sum of their frequencies is only 3.1% of the total sum (23,573). The number of facilities with frequencies greater than 600 is 7, accounting for 4.7% of the total, but the sum of their frequencies is 30.8% of the total.…”

“…For some common facility management issues, data mining technology was utilized to analyze large data sets in the BAS of public buildings such as the tallest building in Hong Kong, with the aim of improving the building operational performance [22]. An optimization algorithm and computational fluid dynamics (CFD) simulations were coupled to improve the aerodynamic behavior of low-rise buildings with flat roofs [23]. Naïve Bayes, decision tree and SVM were also feasible to simplify the procedure of establishing models for predicting internal natural lighting and thermal comfort [24].…”

Three‐Dimensional Aerodynamic Optimization of Single‐Layer Reticulated Cylindrical Roofs Subjected to Mean Wind Loads

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An Investigation into the Distribution of Fluctuating Wind Pressure and Associated Probabilistic Characteristics of Low-Rise Buildings Impacted by the Gap between the Hillside and the Building

“…The influence of the above factors on the first-order statistics of the pressure coefficient is limited, but their influence becomes more pronounced when analyzing high-order statistics (i.e., variance, skewness, and kurtosis) and extreme values. Ye Qiu et al [19] combined optimization algorithms with computational fluid dynamics (CFD) simulations, based on four turbulence closure models (standard k-ε, RNG k-ε, and SST k-ω). For the first time, the performance of solid parapet walls in reducing flat roof suction induced by conical vortices was studied in conjunction with RSM.…”