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Mathematical models and numerical solution procedures for predicting the trajectory, oscillation, possible rotation, and mass and size time-evolution of cylindrical wind-driven firebrands are described and discussed. Two test problems and the results, used for validating the mathematical models, are presented. In one, experimental measurements of non-burning cylindrical particles falling in still air are compared to numerical predictions and in the other, predictions of time-evolution of mass and size of stationary burning particles in air flows are compared with experimental results reported in the literature. Results yielded by the proposed models for a demonstration problem involving cylindrical wind-driven firebrands, with the same initial volume, mass and position, but different initial aspect ratios and distinct initial orientations relative to the wind velocity, are then presented. These results show the following: the horizontal distance travelled by the firebrand from release to landing locations is an increasing function of its initial aspect ratio; and the initial orientation of the firebrand, and its subsequent oscillations including possible rotation, have a significant influence on its trajectory, thus it is important to account for them in mathematical models formulated for predicting the spread of fires by spotting.

In this article, the passive thermal performance of a light steel residential building is studied. A numerical model is implemented and is experimentally validated. The analysis is focussed on the Csb climatic region. Subsequently, this calibrated model is used to assess the importance of several parameters (ventilation, thermal insulation, overhangs shading, windows shade devices, and windows glazing) in the summer and winter thermal performance of this building. Subsequently, based on the cooling and heating seasons thermal performance, an optimum building envelope and operational solution is specified for average Csb climate conditions. Finally, design guidance is provided for the specification of building components and the operation of the building for the range of climatic conditions within the Csb climatic region.

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This paper addresses the influence of the climate change scenarios predicted by the Intergovernmental Panel for Climate Change (IPCC) for Southern Europe and the Mediterranean region on the energy efficiency of light-weight steel residential buildings. A performance-based approach is adopted to carry out this assessment using advanced dynamic simulation of the operational energy performance. Based on a typical Portuguese cold-formed steel residential building, a representative numerical model is calibrated against normative requirements for dynamic simulation of thermal behaviour and sophisticated computational fluid dynamics models. Considering climate change scenarios predicted by the IPCC, a parametric study is carried out to assess the influence of climate change on the energy efficiency of light-weight steel residential buildings representative of a warm temperate summer dry climatic region.