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Breakage and fallout of glazing systems create openings in an enclosure that affect the fire growth and the development of post flashover flames emerging outside of the openings. The behaviour of glazing is the result of its thermally induced stress response to the heat fluxes from the fire in an enclosure. In recent times building façade designs have evolved and now incorporate many different shapes, orientations and materials. The conventional single and double glazing panels have been surpassed by composite type glazing systems including glazing and transparent resins. This paper presents experimental testing of these comp osite glazing panels having different orientations subjected to localized fires, which have the same fire load. The experimental findings of interest include the varying first crack times for both scenarios as well as the variable final crack patterns on the glazing panels. The effect of localized fire on the materials tested as seen in the final char patterns on both glazing systems is also note worthy. The paper also includes details of three-dimensional finite element modeling completed for the prediction of response of the glazing panels at different orientations to the elevated temperatures of the localised fire scenario as tested in the laboratory. This finite element analysis allows for an assessment of glazing thermal stresses at various times throughout each test.

This paper aims to optimise building orientation in Tehran, as well as determining the impact of its shape, relative compactness (RC) and glazing percentage on its optimised orientation.

A cubic module was used and a set of 8 of the same module with 16 different formations were analysed for their orientation (360°), the RC (four groups) and the amount of glazing percentage (25, 50 and 75 per cent).

The results show that the optimised orientation of a building in Tehran strongly depends on its passive solar heat gain elements, their orientation and their position in building; furthermore, glazing percentage amount, amongst the studied factors, plays the most important role in determining a building’s orientation.

The application of the findings of this study in Tehran city planning and also technical details of buildings will lead to a great energy saving in construction sector. Furthermore, the deployment of the proposed design guidelines in construction has explicitly been proven to save a prodigious amount of energy.

The main research question is taken directly from authors’ initiative when working as university professor and research associate. The case study buildings, their morphological configurations and sustainable features have not been presented before in an academic journal.

Understanding the structural performance of external glass curtain walls (façades) during fire exposure is critical for the safety of the occupants as their failure can lead to fire spread throughout the entire building. This concern is magnified by the recent increase in fire incidents and wildfires. This paper presents the first simplified technique to model single-skin façades during fire exposure and then utilizes it to examine the structural behaviour of vertical, inclined and oversized façade panels.

The proposed technique is based on conducting simplified heat transfer calculations and then utilizing a widely used structural analysis software program to analyze the façade. Validation for the proposed technique with reference to available experimental and numerical studies by others is presented. A parametric study is then conducted to assess the structural performance of different glass façade systems during exposure to fire.

The proposed technique was found to provide accurate predictions of the structural performance of glass façades during fire exposure. The structural performance of inclined façade systems during fire exposure was found to be superior to vertical and oversized façade systems.

This research paper is the first to provide a simplified technique that can be utilized to model single-skin facades under fire. The presented technique along with the conducted parametric study will improve the understanding of the fire behaviour of single-skin glass facades, which will lead to safer applications.

This paper aims to present experimental work examining the effect of opening size on the collection efficiency of cavity-type receiver geometries, e.g. modified cavity and spherical cavity with single- as well as dual-stage water heating. The correlations, obtained using the experimentally obtained data, are helpful in designing of cavity receivers (modified and spherical geometry type) to be used in solar-power harnessing assignments/projects, for yielding better system performance.

The parameters of study encompass receiver opening or aperture ratios (d/D, ratio of diameter of opening to the maximum diameter of spherical cavity) of 0.4, 0.47, 0.533 and 0.6; flow Reynolds numbers of 938, 1,175, 1,525 and 1,880 with water as a coolant; and receiver inclination angles of 90, 60, 45 and 30° (with 90° as receiver-opening facing downward and 30° as receiver-aperture facing closer to sideway). A modified cavity receiver was examined for opening ratios of 0.46, 0.6, 0.7 and 0.93. The glass covers, with thickness 2, 4 and 6 mm, were positioned at the opening of cavity to mitigate the energy losses.

The experiments have been conducted at a lesser incoming radiative heat flux, for receiver cavity wall surface temperatures ranging from 90°C to 180°C. The collection efficiency values of both the receivers, modified cavity and spherical cavity types, are seen increasing with coolant flow rate and receiver tilt (inclination) angles, i.e. 30° → 90°. The collection efficiency exhibits maxima at an opening ratio of 0.533 in case of both single- and double-stage spherical cavity receiver. This value was observed as 0.6 for modified cavity receiver. The mathematical correlations developed for obtaining the collection efficiency values of modified cavity-type receiver, spherical cavity receiver with single stage and spherical cavity receiver with dual-stage water heating are given as ɳ=0.4667 Re0.0798dD0.1651 δ0.0281θ̇−0.011, ɳ=0.2317 Re0.124 dD1.265δ0.0192θ̇0.2914 and ɳ=0.1137 Re0.1715dD0.8702θ̇0.2757, respectively.

The findings of the paper may be helpful in erecting concentrating solar collector systems for household water heating, concentrating solar-based power generation as well as for various agricultural applications.

The experimental investigations are fewer in the literature examining the combined geometrical influence on the efficiency of cavity receivers with single- and double-stage water heating provisions.

Two‐dimensional finite difference calculations are carried out to study laminar flow in longitudinal and transverse convection rolls for three different geometries: a single rectangular cavity with high aspect ratio; a double cavity with a thin separation sheet; and a double cavity with a separation sheet and a honeycomb structure. The equations for the convection‐diffusion in the fluid and conduction in the solid region are solved simultaneously. Good agreement with experimental data is achieved for Rayleigh numbers not too high above the critical value for the onset of secondary convection rolls (Ra < 8500 for vertical and Ra < 2700 for horizontal cavities filled with air). Simulation fails for inclined cavities, where the flow structure is essentially three‐dimensional.

The buildings should be designed by respecting the environmental and climatic conditions they are in and their orientation. Then, the characteristics of the building envelope (BE) play an important role in building energy consumption and user comfort. In fact, the type and material of glazing is one of the crucial parameters for BE. The transparency ratio of BE also determines the façade performance. The aim of this study is to analyze the different renovation scenarios for BE with high transparency of an educational building (EB) in hot summer weather to obtain indoor thermal comfort (ITC) for users.

The methodology includes thorough measurement of existing ITC using TESTO-440 and simulation of each retrofit scenario using DesignBuilder building energy modeling (BEM) simulation software with Energyplus to determine optimal thermal comfort. Since the study focuses on the impact of the transparent BE on summer ITC, four main scenarios, naturally ventilated (NV) façade, film-coated glass façade, replacement of glazing with opaque units, sun-controlled façade with overhang and solar shading, were simulated. The results were analyzed comparatively on both performance and cost to find the best renovation solutions.

A total of 7 different renovation scenarios were tested. Simulation results show that passive systems such as NV have limited contribution to indoor air temperature (IAT) improvement, achieving only a 4 °C reduction while offering the lowest cost. A film coating resulted in a reduction of 3–6 °C, but these applications have the highest cost and least impact on ITC. It was found that exterior coating leads to better results in film coating. Preventing and limiting the increase in IAT was achieved by reducing the transparency ratio of BE. The best results were obtained in these scenarios, and it was possible to reduce IAT by more than 10 °C. The best performance/cost value were also obtained by decreasing transparency ratio of roof and sun control.

Since the high transparency ratio has a negative impact on summer comfort, especially in hot climate zones, summer ITC was prioritized in the renovation solutions for the case building.

The study’s findings present a range of solutions for improving the ITC of highly transparent buildings. The solutions can help building managers see the differences in renovation costs and their impacts on ITC to decrease the cooling load of the existing buildings.

This paper, using energy softwares, designed of Iran and optimized a residential villa in Saman city located in Chaharmahal and Bakhtiari Province.

Having used the ideas of Climate Consultant software, the basic designing was conducted by Design Builder Software, and the cooling and heating loads and lighting tools and equipment were calculated. Then, the amount of consuming of heating, cooling and lighting load of the building was optimized through insulation of walls and ceiling, using green roof, double glazing UPVC windows, light intensity sensor and variable refrigerant flow (VRF) system.

Simulation results for the stated scenarios showed an annual reduction in energy consumption of 21.1, 7.9, 26.41, 27.3 and 72.3 per cent, respectively. Also, by combining all the five scenarios, an optimal state was achieved which, from the results, brought about an annual reduction of 86.9 per cent in the energy consumption.

The authors hope that the results of the current paper could be helpful for designers and engineers in reduction of energy consumption for designing a building in similar climatic conditions.

Optimisation of daylight admission through window is crucial for alleviating glare while maintaining useful daylight levels in order to enhance occupants' health, visual comfort and moderating lighting energy consumption. Amongst various solutions, fixed external shade is an affordable solution for housing spaces that need to be sophisticatedly designed, especially during the period of increasing home spaces as working environments. In the humid subtropical region, daylight control plays an important role in indoor comfort, particularly with areas with a high window to wall ratio (WWR). Due to the insufficient amount of such study on non-office spaces in Australia, shading-related standards are not addressed in Australian building codes.

The chosen methodology for the research is a quantitative data collection and analysis through field measurement and simulation simultaneously. The first step is a multi-objective optimisation of shading elements through a non-dominated sorting genetic algorithm (NSGA-II) on parametric modelling via Rhino3D CAD and simulation engines (DIVA and ClimateStudio). In the second phase, the Pareto front solutions are validated by experimental measurements within a room with a single north-facing window (the most probable for the daytime glare in Sydney) for the seven most common local window configurations.

Through the simulation of ten genes, 1,560 values and 2.4 × 1,019 of search space, this study found an optimum shade for each local common window layout, resulted in +22% in (UDI) and −16% in views with discomfort glare on average. Moreover, an all-purpose polygonal shade showed an average of 4.6% increase in UDI and a 5.83% decrease in the percentage of views with discomfort glare.

The findings are subject to the room dimensions, window dimensions and layouts, and orientation of windows for selected residential buildings in Sydney.

The study contributes to the development of highly accurate fixed external shading systems with rectangular and tapered-form external shapes. A real-time measurement by luminance-metre sensors and HQ cameras located at six eye levels is conducted to corroborate simulation results of the visual comfort.