Different Types Of Glazing Research Articles

Efficient Daylighting: The Importance of Glazing Transmittance and Room Surface Reflectance

This study quantitatively analyzes the influence of the spectral characteristics, reflectance or transmittance, of different materials on the lighting of an interior space with natural and artificial light. For this purpose, a three-dimensional simulated classroom is used, where each of the components is assigned specific materials with an associated reflectance or transmittance. Additionally, two types of lighting are available: 6500 K daylight and light from six continuous spectrum LED luminaires. The lighting is evaluated on two planes: the work plane and the corneal plane (80 cm and 120 cm from the floor, respectively). Three versions of the same classroom were analyzed by varying the walls (white, blue, and red), each with a different neutral-colored floor. Furthermore, calculations were performed in each situation considering two different types of glazing in the windows, with 20% and 88% transmittance. The photopic and melanopic lighting analysis was carried out with the ALFA calculation program to verify the necessary requirements for adequate lighting. The results show that the white classroom is the best lit, followed by the blue and finally the red, due to the reflectance characteristics of the walls and floor although slight differences among them are found. It was found that in some cases, additional auxiliary luminaires would be required for proper lighting depending on the transmittance of the glazing. This study highlights the critical role of material selection in optimizing both photopic and melanopic lighting, with practical implications for energy efficiency and occupant well-being in educational spaces.

Non-Invasive Raman Classification Comparison with pXRF of Monochrome and Related Qing Porcelains: Lead-Rich-, Lead-Poor-, and Alkali-Based Glazes.

Chinese porcelain with an optically clear colored glaze, imported to Europe from the Kangxi period (1662-1722, Qing Dynasty) onwards was highly collected by the French Elite of the 18th century. The bright colors with a clear, shiny glaze were unlike anything produced in Europe at that time. The colors of enamelled artifacts (on biscuits or already glazed porcelain) can be fully monochrome or consist of associations of large monochromatic areas with or without application of gilding. Non-invasive portable XRF and mobile Raman analyses have previously shown their effectiveness in the characterization of (colored) glassy silicates. In this study, we compare the Raman signatures of twenty-one Chinese artifacts fully-or with major monochrome area (sancai)-decorated with blue, turquoise (or celectian blue), honey-yellow, green, eggplant, and red color. Different types of glazes are identified and confirmed by pXRF: lead-rich, lead-poor-alkali, lead-doped alkali, and alkali-based compositions. However, an unexpected low level of lead is observed in the turquoise glazes, likely to optimize the gloss. Raman spectroscopy appears more reliable to compare the Pb content than pXRF. This work presents Raman spectral signatures of glazes that can potentially be used for non-invasive object classification and counterfeit detection.

Daylight and energy performance of side lighting systems in an office room in a subtropical climate

In office buildings, daylight is an important natural resource, as it is profusely available during occupied hours. However, its use can increase energy consumption for air conditioning. Therefore, combining this resource with side lighting systems and promoting its integration with electric lighting is essential to obtain an energy balance. This paper aims to analyze daylight performance and the energy consumption for lighting and air conditioning considering four types of glazing, four orientations, from window-to-wall ratios varying between 40% to 100% for bare and shaded window models in an office room located in a subtropical city in southern Brazil. The methodology was based on Useful Daylight Illuminance levels of 500 to 2,500 lx, Daylight Autonomy levels of 500 lx, and total energy consumption through simulation in DesignBuilder software. The results showed that L13 glazing is not recommended for bare and shaded windows, regardless of window orientation. M76 presented the best performance for energy consumption for West shaded windows. For the West, shading is necessary irrespective of the glazing type (except L13, whose best performance is for bare windows) from WWR 50%. M76 and M52 had the lowest total energy consumption. The findings of this study add to an understanding of the energy savings and lighting performance of different types of glazing, combined with window apertures, and solar orientations for a subtropical climate. Furthermore, the study shows that the choice of glazing depends not only on the presence of shading but also on the orientation and WWR, without a linear behavior.

Influence of Transparent Envelope Parameters on Office Building Energy Use Intensity in the Different Thermal Climate Regions of China

The role of the transparent envelope in energy savings is crucial as it accounts for a significant proportion of the total energy loss (between 30 and 40%). This paper focuses on the identification of reasonable parameters for the transparent envelope in different climatic regions. To achieve this goal, typical urban office buildings from four different climatic regions are used as research objects. A total of 1600 scenarios were simulated to investigate the variation of energy use intensity, including transparent envelope parameters, meteorological parameters and different types of glazing. The results show that for south-facing transparent envelope facades, type D glazing is the most energy efficient in severe cold regions, type C in colder regions and type B in the other two climatic regions. No solar shading is required in the very cold region. Horizontal shading can be an effective method for saving energy in colder climates, while comprehensive shading can be beneficial in other regions. Deep shading is particularly energy efficient if it meets lighting requirements. For example, in Guangzhou, energy savings of 13.46%, 15.47%, 7.01% and 7.02% can be achieved in the east, west, south and north directions, respectively, using B-type glazing and a comprehensive shading depth of 900 mm.

Environmental degradation of structural glass systems: A review of experimental research and main influencing parameters

Several factors, including incentives associated with aesthetics, transparency, high chemical, and mechanical durability, and its excellent corrosion resistance, have rapidly accelerated the interest and use of glass as windows, façades, or load-bearing elements in structural applications. Nonetheless, the glass is chemically attacked when subjected to certain environmental conditions and its chemistry, structure, as well as its optical and mechanical properties, are altered by the different weathering processes throughout its service life. Several techniques exist for evaluating the performance of weathered glass. These include both natural and artificial ageing techniques. However, little correlation has been shown to exist between natural and artificial ageing, especially the comprehensive comparison between the naturally aged and artificially weathered glazing systems have yet to be examined. In this review paper, the weathering of structural glass systems when exposed to environmental conditions is presented. Emphasis in the literature has been placed chiefly on the different types of glazing in the construction industry and their resistance to three main weathering agents: humidity, temperature, and soiling. Main optical and mechanical tests reported in the literature are summarized, and the properties described in each of them are examined, providing evidence of current challenges, limitations, and insight on future prospects.

An evaluation of the glazing type impact on building energy performance through a building simulation

Buildings are responsible for most of the energy consumption in countries, thence energy saving in buildings is a high priority issue. Windows and glazing types are one of the factors that greatly affect the performance of buildings, both in terms of thermal comfort and energy consumption for heating or cooling. The proper selection of window glazing is one of the effective strategies to minimize energy consumption. In this study, an office building was designed to determine the most suitable glazing type for office buildings, which is the main purpose, and the energy efficiency of the building was examined with Openstudio and Energyplus software. Energy modeling of the office building was conducted for four different types of glazing by using VRF systems for air-conditioning and a dedicated outdoor air system for ventilation. The effect of different windows glazing system properties on the energy performance and total energy need was calculated by considering the fixed indoor thermal and visual comfort conditions were evaluated. The study results indicated that energy consumption can reduce about 24.88 kBtu/ft2 (25%) using suitable glazing material.

Conventional and Advanced Glazing Technologies for Enhancing Thermal and Lighting Performance

Glass is one of the oldest man-made material that is widely used in architecture. As it is a translucent material, it permits a full penetration of direct sunlight but may also increase the internal space temperature and then increasing cooling loads and energy consumption. As the need for energy optimization is very important and glazing is considered a weak point in any building, the selection of glazing assumes tremendous significance. This paper reviews the different types of glazing which can be categorized into conventional and advanced to optimize the thermal and the lighting performance according to their properties and insulation values. Conventional glazing includes the clear glazing whether it is single double or triple, the tinted glazing, the reflective glazing, and the low-E glazing. Advanced glazing which is mainly the insulated glazing unit such as the gas filled glazing, the vacuum glazing, the aerogel glazing and the phase change material glazing.

Use of Local Omani Clays with Low and Mid-Range Temperature Glazes for Art Educational Purposes: Possibilities and Limitations

In this study, red clays, the main industrial material of the Alanwar Ceramic Tiles Plant (ACTP) in Oman, were investigated for use in making glazed ceramics in local educational institutions. Different low and mid-range temperature glazes, which contained various compositions and properties, were examined in the glazing lab at Sultan Qaboos University. The study’s aims were to develop and test low- and mid-range temperature glazes to explore if they could fit the red clays used by ACTP, so that the surface could be adhesively bonded. The laboratory glazes were obtained following technical rules to confirm the possibility of using different types of glazes on ACTP clays in Omani schools and universities. This could help reduce the cost of importing clays from overseas to use in Omani education institutions.

Energy savings and daylighting evaluation of dynamic venetian blinds and lighting through full-scale experimental testing

Commercial buildings consume around 20% of the total energy utilized in the U.S. The use of shading devices in buildings has the potential to reduce building energy consumption while also providing a more desirable indoor environment for building occupants. Similarly, lighting device controls help reduce lighting energy consumption as well as internal loads. However, there is lack of full-scale experimental testing of integrated dynamic shading and lighting controls. This study presents full-scale experimental testing data to quantify these energy and daylighting impacts. Testing was performed utilizing two different control strategies, in three different orientations under three different types of sky conditions. The shading device was also used in conjunction with two different types of glazing. An average of 25.4% cooling energy savings and 48.5% lighting energy savings was achieved. Visual discomfort evaluated using Simplified Daylight Glare Probability was prevented more than 85% of time during occupied hours. Improvement in daylight levels evaluated using Useful Daylight Illuminance was also achieved. Finally, analysis of the relationship between the illuminance level measured at the work plane and a ceiling illuminance sensor is performed to translate the real-world applicability of shading device controls.

Numerical studies of thermal comfort for semi-transparent building integrated photovoltaic (BIPV)-vacuum glazing system

Building integrated photovoltaic (BIPV)-vacuum system is promising for advanced window application due to its ability to reduce heat transfer, control over admitted solar heat and generates environmentally benign electricity. In this work, numerically thermal comfort for an unfurnished room comprising of BIPV-vacuum glazing was evaluated for the United Kingdom (UK) climate. Required parameters to determine thermal comfort, one-dimensional heat transfer model was developed and validated for BIPV-vacuum glazing and results were compared with BIPV-double-pane glazing system. PV cell temperature difference between these two different types of glazing was 24 °C. For the UK climate, BIPV-vacuum glazing offered 26% higher room temperature at clear sunny day compared to BIPV-double system. BIPV–vacuum glazing system provided soothing or comfortable thermal comfort during mid-day period for a clear sunny day at temperate climate. In a combined BIPV-vacuum glazing, it was also predicted that vacuum glass facing external ambient is suitable for the UK climate whilst vacuum glass facing internal room ambient is applicable for Indian climate.

Thermal performance analysis on different types of glazing of public rental housing in Hong Kong

Thermal properties of glazing facades and windows system may affect the solar heat gain through its heat transfer area to an enclosed built environment, eventually affects the electricity consumption of air-conditioning system. Advanced glazing technologies offer a lower solar heat gain. This research project examines the relationship between the types of glazing, orientation and window-to-wall ratio (WWR) against the solar heat gain through the fenestration and annual electricity end uses for a window-typed air-conditioning system, by means of building energy simulation software, EnergyPlus. Reduction of electricity end uses and windows heat addition for the same windows configuration with different advanced glazing ranges are 13.8% and 69.1% respectively, in Hong Kong. The relationship among different construction configuration and climate is investigated. The optimum choice of glazing for minimizing the heat gain and maximizing the visual transmissibility is also suggested in accordance to the simulation results.

Nano Mg1−xNixAl2O4 spinel pigments for advanced applications

Nano Mg1−xNixAl2O4 spinel pigments were synthesized via polymeric combustion technique upon heat treatment at 210°C. Citric acid in the presence of ethylene glycol polymer, with mass ratio of 60:40, was successfully used as a host network for the synthesis process. The obtained spinel was calcined at different temperatures; 300–1200°C and investigated by thermal analysis (TG-DTG/DTA), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). UV–Vis and diffuse reflectance spectroscopy (DRS) using CIE-Lab/parameters methods have been used for color measurements. The addition of colored pigment on different types of glazes was studied. The results revealed that NiMgAl2O4 spinel beside MgNiO phases were crystallized with particle sizes of 9–21nm at 600°C and 52–180nm at 1200°C. All prepared samples exhibited green to pale green colors due to the inclusion of Ni2+ inside the spinel structure. The pale green color intensity increased with increasing calcination temperature. The prepared pigment was suitable to convert commercial and opaque glazes to color product to be used in different applications.

Substitution of a fraction of zircon by cristobalite in nano hematite encapsulated pigment and examination of glaze application

Hematite pigment has a long history, but it cannot be used for ceramic application, because it must be thermally and chemically stable at high firing temperature when using a pigment in a glaze or ceramic body. Recently, through encapsulated systems, a new pigment with suitable thermal and chemical stability can be obtained by encapsulating hematite crystals into selected silica or zircon matrices. It means that nano-sized red hematite has been encapsulated into the protected phases. Transmission electron micrographs of hematite encapsulated into silica and zircon matrices by sol-gel method show spherical single crystals with diameter of about 5–10 nm. In order to optimize ceramic glaze formulations for application of the synthesized red inorganic nanocomposite inclusion pigment by sol-gel method, four different types of glazes (i.e., alkalis, borate, earth alkalis, and leaded glazes) have been tested. The results show that the substitution of a fraction of zircon by cristobalite in hematite-zircon pigment produces acceptable stability with red hue.

Acoustic failure analysis of windows in buildings

Poor acoustic insulation of building façades is largely influenced by the component assembly of the window and by the installation of the window in the wall. For the first, a poor gasket design and poor gasket installation during the window assembly will usually lead to whistle noises inside the rooms, especially next to busy roads. For the latter, the choice and installation of obturating materials in the cavity between the window and the wall may lead to a decrease in acoustic insulation in a wider range of frequencies. Consequently, the objectives of this investigation are to evaluate different methods to detect acoustical failures in openable windows in walls, and to present an efficient approach to optimise the sound insulation of a façade. By means of experimental measurements on a standard openable window, two different and complimentary approaches are compared to evaluate the acoustical quality and failures of the gaskets and the final setup of the window. More specifically, the first type of measurement is based on a standard sound insulation measurement of the façade according to ISO 140-5, and the second consists of ultrasonic measurements. The acoustic impact of the cavity between the window and the wall is evaluated in the laboratory according to ISO 140-3. For this research two different and most common materials are used to obturate the gap: polyurethane foam and mineral wool. The impact of these different types of materials is evaluated against different types of glazing. On the one hand side, standard sound insulation measurements enable to evaluate the quantitative impact of different parameters governing acoustical failures, such as discontinuity, incorrect placement and wrong selection of both gaskets and obturating material. On the other hand, ultrasonic measurements enable a quick qualitative assessment that is very efficient to determine the exact position of the acoustic leaks in the façade. Finally, a combined use of standard and ultrasonic measurements is proposed to deliver an efficient approach to detect acoustical failures of windows. The ultrasonic approach is a quick and cost-effective way to instantly track workmanship deficiencies of a window on site, whereas the standard measurements are more time consuming but needed to guarantee the performance of a building element.

Chemical and mineralogical characterization on glazes of ceramics from Coimbra (Portugal) from the sixteenth to nineteenth centuries

Chemical, mineralogical and textural characterizations were performed on glazed pieces prepared in laboratory as well as on faiences fragments collected from the existing remains in "Santa Clara-a-Velha" monastery (Coimbra, Portugal). The chemical investigation was carried out using micro X-ray fluorescence (micro-EDXRF) and wavelength dispersive X-ray fluorescence (WDXRF); the mineralogical results using X-ray diffraction (XRD) and the textural profile was obtained by scanning electron microscopy coupled with an energy dispersive spectroscopy system (SEM-EDS). Attention has been drawn to the glaze mineralogical changes during the firing temperature process, where three different types of glazes were submitted to three different firing temperatures (800 degrees C, 900 degrees C and 1,000 degrees C). Under these conditions, it is possible to relate the mineralogical content of the fragments to their firing temperature. Furthermore, we focused our purposes on identifying the technological aspects of the ceramic production in Coimbra, such as the raw materials, manufacture techniques and firing temperature adopted for the glaze. The latter aspect is highly dependent on the ceramic materials. In the framework of a more general project, this survey has as premise the recognition of a pattern, which is thought to be exclusively typical from the region of Coimbra. The perspective developed in the present work is towards reliable archaeometric criteria, which can be used to characterise scientifically the ceramics from Coimbra.

SEM Analysis of the in situ Early Bacterial Colonization on Two Novel Feldspathic Ceramics Submitted to Different Types of Glazing

The aim of this study was to evaluate in situ, the early bacterial colonization on feldspar-ceramics submitted to different glazing. Fourteen standardized disc specimens (diameter: 5 mm, thickness: 1.5 mm) of each of two micro-particulate feldspathic ceramics (VM7 and VM13, Vita) were produced according to manufacturers' specifications for a total of 28 specimens (24 for the analysis of biofilm and 4 for topographic analysis analyzing the ceramic surfaces). Specimens from each type of ceramic were submitted to two different glazing methods composing four groups: VM7 glazed using glazing liquid Vita Akzent 25 (G1) and glaze firing (G2), VM13 glazed using glazing liquid (G3) and glaze firing (G4). Six individuals (n=6) wore oral appliances with four ceramic specimens, fixed on the buccal face of the appliances. After 8 hours, each sample was evaluated for the presence (1) or absence (0) of bacterial colonization under a scanning electron microscope (SEM) on five randomly selected fields. The value for each sample was cumulative of the results observed in the fields. One sample from each group was evaluated under a SEM to verify the topographic pattern. There was no difference with regard to bacterial colonization between the feldspar-ceramics and between the glazing types (Kruskal-Wallis non-parametric test). Feldspar-ceramics submitted to firing or glaze firing with Vita Akzent 25 present a similar condition for in situ bacterial colonization. The similar topographic pattern of the ceramic surfaces seems to have influenced the bacterial colonization.

On‐site Raman analysis of the earliest known Meissen porcelain and stoneware

AbstractOn‐site Raman analyses were performed at the Musée national de Céramique, Sèvres, France, on select rare items of the earliest known European hard‐paste porcelains and stonewares, produced from ca 1710 to 1750 in the Meissen workshop (Saxony) founded by J. F. Böttger and E. W. von Tschirnhaus. Characteristic on‐site Raman signatures have been obtained for white Sake bottles from ca 1715, a green bowl depicting a purple landscape dated 27th August 1726 and a figurine and coffee cups produced in the middle of the eighteenth century. In addition, some artefacts (a red polished stoneware cup from ca 1710 to 1715, a white ewer stopper from ca 1725, a blue underglaze decorated flat stopper believed to have been manufactured after 1719 and decorated coffee cups) were analysed at the laboratory. Raman spectra identified different types of mullite‐rich bodies, including calcium‐rich and quartz‐containing pastes. Different types of glazes and pigments (haematite, Naples yellow, cassiterite, lapis lazuli, etc.) have also been identified. The results are discussed in the light of previous chemical analyses and historical records. We propose characteristic parameters to discriminate between the different production technologies. Copyright © 2006 John Wiley & Sons, Ltd.

Effects of cobalt, copper, manganese and titanium oxide additions on the microstructures of zinc containing soft porcelain glazes

Abstract Different types of glazes, which are nearly all based upon silicate compositions, are used to meet a wide range of requirements in service. Many artistic effects are achieved by departing from a clear, smooth, transparent system. Coloured glazes are produced by several means such as the inclusion of colouring oxides, addition of stains, dispersing finely divided particles and the use of precious metals, applied in the form of lines or bands, or even screen-printed patterns. Colouring oxides commonly used include iron, copper, cobalt, chromium, manganese, nickel, vanadium, cadmium and selenium. Zinc oxide has a beneficial effect in many coloured glazes amongst which crystalline ones are more noteworthy. With this paper the effects of CoO, CuO, MnO 2 and TiO 2 additions into zinc oxide containing crystal glazes differentially heat-treated are described on micro-scale appearances. Experimental techniques used were X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer (EDX).

Modeling the influence of glazed openings percentage and type of glazing on the thermal zone behavior

The selection of the type of glazing as well as its proportion to the total wall area are very important towards achieving a desirable indoor environment. This paper uses a dynamic thermal-circuit zone model to study the influence of the glazed openings percentage (GOP) and type of glazing on the maximum and minimum indoor temperatures, during and after solar hours. The model comprises of four major structural heat-flow paths, corresponding to the external and internal walls, glazing and horizontal slabs. The simulation is performed for winter and summer seasons and for a zone with and without a power plant, with an external wall having south orientation. In the latter case, the optimum GOP leading to the minimum energy consumption is determined. The zone formation comprises masonry walls with insulation in the center plane, concrete horizontal slabs with and without insulation and three different types of glazing (double, double with low emissivity (low- ε) coating and double with reflective film). As GOP varies, computer results show how the type of glazing and the insulation of the slabs affect the indoor zone temperatures and energy efficiency.

On the effect of glazing and code compliance

The trend for modern buildings to be designed with large glazing areas in the exterior envelope is becoming more popular than ever before. At the same time, the power utilities in most of Kuwait demand code compliance through targeting of peak electric requirements for heating, ventilation and air-conditioning (HVAC) systems. The lack of detailed and accurate information on the thermal performance of glazing systems coupled with limits set by the code of practice can result in bad building design with respect to indoor comfort conditions. This paper presents a methodology for selecting glazing areas, while keeping the peak-load demand fixed. Provisions for the selection of large glazing areas are based on the type of glazing used. Finally, using a multi-storey building in Kuwait as an example, analysis has been conducted for seven different types of glazing. The choice of glazing offers the designer significant flexibility in opting for a glazing area of between 20 and 100%, and yet achieving full compliance with the code.