A three dimensional numerical wind tunnel based on the Navier-Stokes equations for viscous, incompressible fluid and LES method is established. Incoming wind field is generated based on the AIJ guidelines (2004). The numerical wind tunnel is validated against experimental results. A low-rise building with green roof is tested in the numerical wind tunnel. The results show that the green roof re...

Cool roofs represent an acknowledged passive cooling technique to reduce building energy consumption for cooling and to mitigate urban heat island effects. This paper concerns the evaluation of the dynamic effect of new cool roof clay tiles on building thermal performance in summer and winter conditions. To this end, these properties have been analyzed on traditional roof brick tiles through an...

For centuries, dome roofs were used in traditional houses in hot regions such as the Middle East and Mediterranean basin due to its thermal advantages, structural benefits and availability of construction materials. This article presents the computational modelling of the windand buoyancy-induced ventilation in a geodesic dome building in a hot climate. The airflow and temperature distributions...

An experimental study was conducted to quantify the characteristics of a tornado-like vortex and to reveal the dynamics of the flow-structure interactions between a low-rise, gable-roof building model and swirling, turbulent tornado-like winds. The experimental work was conducted by using a large-scale tornado simulator located in the Aerospace Engineering Department of Iowa State University. I...

This paper proposes a method for the automatic extraction of building roof contours from a LiDAR-derived digital surface model (DSM). The method is based on two steps. First, to detect aboveground objects (buildings, trees, etc.), the DSM is segmented through a recursive splitting technique followed by a region merging process. Vectorization and polygonization are used to obtain polyline repres...

We assessed the total energy required to manufacture, install and maintain an extensive, sedumplanted green roof over its assumed life of 20 years in the Mid-Atlantic region of the U.S. using the method of emergy analysis. We estimated its environmental benefits as the sum of summer electricity savings due to cooler building temperatures, primary production of biomass and reduction in intensity...

This paper presents an interactive system for producing polyhedral and prismatic building models. The core technology, called “Split-Merge-Shape” (SMS) method, reconstruct building models from photogrammetric 3-D line-segments of buildings, i.e. the roof-edges. The method may treat those complete line-segments as well as partial line-segments due to image occlusions. The proposed method compris...

This paper presents an approach to creating a polyhedral model of building roof from LiDAR point clouds using clustering techniques. A building point cloud is first separated into planar and breakline sections using the eigenvalues of the covariance matrix in a small neighbourhood. The planar components from the point cloud are then grouped into small patches containing 6-8 points and their nor...

The components and claddings of low-rise building are usually destroyed first during typhoon disasters in coastal areas. Roof accessory structures can change the flow pattern on the roof, thus effectively reducing the wind load on the roof surface and the damage to the low rise buildings. Two types of aerodynamic mitigation plates, i.e., (1) 0.3 m high full length roof-edge plate, and (2) 0.3 m...