Numerical study of wind environment of a low-rise building with shading louvers: sensitive analysis and evaluation of cross ventilation

Abstract

Shading louvers are widely used in buildings to protect the indoor environment from excessive heat gain, especially in hot climatic regions. However, few studies mentioned their influences on wind characteristics. As a type of external components on building facades, shading louvers play an important role in wind-induced physical fields, such as wind pressure distribution and airflow pattern. The purposes of this paper are to analyse the impact of computational parameters on simulation results and evaluate the cross-ventilation capacity of a low-rise building with shading louvers. The rotation angle of shading louvers is considered. The simplified engineering model and the coupled indoor and outdoor airflow model are introduced to perform cross-ventilation evaluation. The sensitive analysis shows that the turbulence model has the greatest impact on numerical results. The evaluation of cross ventilation shows that the simplified model fails to quantify the cross-ventilation capacity for some cases. Based on the coupled airflow model, the largest reduction of ventilation rate is up to 66.6%. This study has performed the first sensitive analysis for airflow fields around the building with shading louvers, which provides a detailed simulation guidelines. The results of cross-ventilation capacity influenced by the shading louvers is helpful for ventilation design.

Investigation of varying louver angles and positions on cross ventilation in a generic isolated building using CFD simulation

“…A reduction in the volume flow rate therefore causes a decrease in the DFR. Such findings are similar to that of other authors (Kosutova et al, 2019;Chandrashekaran, 2010;Zheng et al, 2020) who studied the performance of various louver angles with varying A E .…”

“…Center-center louvers at 0 • exhibit an interesting characteristic where the reduction in effective opening area, A E increases the DFR instead of decreasing it. This has also been observed Moey et al (2021b); where the author's louver configuration at 0 • center-center location had a higher DFR than the center-center configuration without louvers and as well as by Zheng et al (2020).…”

“…Recent papers by Zheng et al (2020) studied the effects of shading louvers on natural ventilation with varying angles. The performance of non-shaded louvers and shaded louvers of 0 • , 15 • , 30 • , 45 • , 60 • and 75 • at velocity 3.41 m/s were studied.…”

Using CFD to Evaluate Natural Ventilation through a 3D Parametric Modeling Approach

“…Consequently, several studies are concentrated on measuring, evaluating, and predicting this passive strategy, especially in recent years because of sustainable and energy demand goals [16,32]. Some emphasize either cross-or single-sided ventilation, investigating specific topics such as the impact of the building dimensions [33], internal divisions [34], multiple windows [35], sheltering [36,37], adjacent obstacles [38,39], wind exchangers [40], large openings [41], and a greenhouse with a wind tower [42]. Moreover, Dai et al [43] study air quality and virus propagation in interunit dispersion in multistory buildings.…”

Dispositivos de sombreamento: avaliação do impacto no desempenho da ventilação natural

“…Já os superiores indicaram reduções nos valores de Cp para aumentos tanto na largura quanto na profundidade das sacadas. A consideração do entorno imediato impactou significativamente os Cps, com registro de valores negativos nas faces a barlavento.É crescente a literatura acerca de investigações dos chamados louvers na ventilação natural(TABLADA et al, 2009;SACHT et al, 2016;LEE et al, 2015;LI, 2020;KOSUTOVA et al, 2019; LI, , 2020bJIANG et al, 2019;CHANDRASHEKARAN, 2010). Alguns estudos os caracterizam como grelhas para ventilação, outros atribuem a mesma terminologia para uma subestrutura composta,…”