Glass Panels Research Articles

Case Study on the Re-use Potential of Insulated Glass Units

Glass is an energy intensive material that is essential to buildings and their energy consumption. Its transparency allows for natural daylighting and the use of solar heat gains. In the context of the refurbishment politics of the EU as a result of the Paris Agreement on climate goals, significant amounts of glass waste in form of windows and façades are to be expected. In order to minimize the environmental impact of glass by preserving the embodied carbon and substitute newly produced glasses, the Re-use of glass is considered to be of highest potential. When reusing panes, energy and raw material can be saved that otherwise would be consumed for the production of new glass. This way, the common principles of sustainability - sufficiency, efficiency and consistency - can be realized for the life cycle of flat building glass. The following case study estimates the potential of different scenarios for circular waste treatment of glass panes by applying the 9R Framework to insulating glass units (IGUs). The scenarios are defined and presented. A life cycle assessment (LCA) using identical system boundaries for these scenarios was executed and the results are compared to producing IGUs entirely with new glass. Finally, the feasibility of the strategies is evaluated and recommendations for the processing of glass in stock are derived.

Stress Distribution along the Structural Sealant Joint Length of a Cylindrically Curved Glazing Panel

It has been identified that current standardised method for structural sealant joint dimensioning is applicable to flat rectangular panels only and no provisions are made for panels with curved surfaces. The purpose of this study is to investigate the stress distribution along the sealant joint of a cylindrically curved glass panel subjected to wind pressure and to establish if the panel curvature influences the stress distribution along the joint length. Using numerical method, several curved units were analysed and the results have shown that the out of plane wind action generate compression and shear forces within the joint, both occurring at the same time. This means that in the case of a structurally bonded curved panel, additionally to the shear caused by differential thermal expansion of elements or glass self-wight which is covered by ETAG 002 and EN 13022 the designer must also consider the shear stress induced due to the panel curvature. The magnitude and location of this additional shear stress and also of the tension/compression stress can be identified using Finite Element Analysis.

Predictive Analysis of Laminated Glass Performance Under Static and Dynamic Loading Conditions

Laminated safety glass is normally used when there is a possibility of human impact or where the glass could fall if shattered. Glass laminate films, the plastic film called an interlayer that is adhered between sheets of glass, are an important component of many glass applications. In an event that causes breakage of the glass, it is held in place by an interlayer, between its two or more layers of glass. The interlayer keeps the glass bonded even when broken, and its high strength prevents the glass from breaking up into large sharp pieces. Various physical tests (standard/non-standard) can be found in the literature to develop and screen the different interlayer materials. In the last several years, we have witnessed extensive growth in computational modeling of complex nonlinear behavior of laminated glass panels with viscoelastic interlayers. To evaluate the mechanical behavior of laterally-loaded interlayer in laminated safety glass, finite element (FE) modeling is widely used in industry. Recently, FE modeling techniques and methods helped to identify selection criterion for proposed materials to be used in the interlayer of laminated glass. The present study aims to develop a numerical model (Finite Element model) verified by experimental results/data given in literature and to utilize the model to examine the mechanical behavior of laterally-loaded interlayer films in laminated safety glass subjected to standard/non-standard tests (four-point bending test and Impact test) conditions. Also, parametric studies (effect of interlayer/glass thickness, impactor speed, soft/stiff interlayer material etc.) are performed through FE analysis to investigate the impact of these parameters on the behavior of the interlayer material.

Thin Glass Installation

The architectural prominence of glass structures, driven by ongoing innovations in manufacturing and post-processing techniques, reveals the material's remarkable structural potential. Aluminosilicate glass, distinguished by superior strength and flexibility, particularly in comparison to soda lime glass, facilitates the production of ultra-thin glass with thicknesses as low as 25 μm. This has led to the emergence of "thin glass," defined as any glass below 2 mm in thickness. Thin glass, celebrated for its unique attributes, has found diverse applications in industries like automotive and electronics. In architecture, thin glass holds potential for creating complex, lightweight, and transparent architectural structures. This paper addresses the constraints of thin glass in construction and explores optimal bending techniques to maximize its potential through a detailed study of its properties. The current study establishes design guidelines and a computational approach for utilizing cold bent thin glass in the design process. The findings showcase a successful computational method providing tools, design principles, and guidelines for working with single curved cold bent thin glass panels. The paper also examines suitable connection types for thin glass projects, proposing a hinge clamp connection. A case study illustrates the proposed workflow, resulting in a prototype using a 3D-printed approach for the suggested connection design.

Effects of Nanocoating on the Performance of Photovoltaic Solar Panels in Al Seeb, Oman

Solar photovoltaic (PV) panels are projected to become the largest contributor of clean electricity generation worldwide. Maintenance and cleaning strategies are crucial for optimizing solar PV operations, ensuring a satisfactory economic return of investment. Nanocoating may have potential for optimizing PV operations; however, there is insufficient scientific evidence that supports this idea. Therefore, this study aims to investigate the effectiveness of nanocoating on the performance of solar photovoltaic (PV) panels installed in Al Seeb, Oman. A further study was also carried out to observe the influence of coating layers on the performance of PV panels. One SiO2 nanocoated solar panel, another regularly cleaned PV panel, and a reference uncleaned panel were used to carry out the study. The site of the study was treeless and sandy, with a hot and dry climate. A data logger was connected to the solar PV panel and glass panel to record the resulting voltage, current, temperature, and solar radiation. It was observed that nanocoated PV panels outperformed both regular PV panels and uncleaned PV panels. Nanocoated PV panels demonstrated an average efficiency of 21.6%, showing a 31.7% improvement over uncleaned panels and a 9.6% improvement over regularly cleaned panels. Although nanocoating displayed high efficiency, regular cleaning also contributes positively. Furthermore, even though nanocoated PV panels outperformed the other two panels, it is important to note that the performance difference between the regular cleaned PV panels and the nanocoated PV panels was small. This indicates that regular cleaning strategies and nanocoating can further contribute to maintaining a more efficient solar PV system. Coating in many layers was also observed to influence the performance of PV panels insignificantly, mainly the fourth layer coating appeared to have formed sufficient mass to retain heat.

Crack segmentation for high-speed imaging: detection of fractures in thermally toughened glass

Fracture morphology characterization in broken glass panes is crucial for designing laminated safety glass (LSG) in civil engineering. Verifying completely broken LSG systems requires destructive sampling, increasing costs and hindering development. Therefore, to determine the residual load-bearing capacity, the link between the pre-fracture characteristics and the fracture morphology must be known. However, when the crack propagation needs to be directly captured with high-speed imaging, conventional methods are no longer sufficient for detecting cracks. To enable such investigations, we propose a novel machine learning framework for crack segmentation in high-speed imaging that addresses the complexity of glass fracture and minimises the required labour costs. In this study, the crack propagation of a sample was recorded and analysed at 2,000,000 images per second. The results showcase accuracies surpassing 97% while requiring only two labeled images for training, thus streamlining practical implementation. Furthermore, we show the method's robustness to the extent that hyperparameter tuning becomes unnecessary. Instead, we offer guidelines for selecting the most crucial hyperparameters depending on the problem. Our method offers a promising approach for non-linear temporal interpolation of noisy images, with implications for various applications extending beyond glass fracture analysis.

Influence of a multilayer interlayer with a stiff core on the performance of laminated glass

Laminated safety glass is an important component of modern façade structures and is used when higher safety requirements are demanded. The interlayer increases the stiffness due to the available shear action, ensures the residual load-bearing capacity of the structure in the event of failure and holds broken pieces of glass in place. However, the stiffness and tensile strength of conventional interlayers such as EVA or PVB are known to strongly depend on time and temperature. This phenomenon is particularly critical for the behavior of glass panes during impact and after breakage when high tensile stresses occur in the interlayer. A film with higher stiffness, lower time and temperature dependence can be laminated between two layers of interlayer material to improve laminated glass behavior. Given the need to conserve resources and reduce weight, the question arises as to whether such an interlayer could also be used to meet the safety requirements for laminated glass made out of thin glass. In this study, the influence of a multilayer interlayer of EVA and a stiff core film of modified polyester (MPE) in glass laminates was examined. For this purpose, the material and composite behaviors were experimentally studied and evaluated. This article presents the test setup and the results. The focus is on comparing the properties of interlayers with and without MPE films. The results show that the impact strength of thin glass laminates is improved by the multilayer interlayer.

Virtual social grooming in macaques and its psychophysiological effects.

Allogrooming is a widespread, pervasive activity among non-human primates. Besides its hygienic function, it is thought to be instrumental in maintaining social bonds and establishing hierarchical structures within groups. However, the question arises as to whether the physiological and social benefits derived from social touch stem directly from body stimulation, or whether other mechanisms come into play. We address this question by analyzing an elaborate social behavior that we observed in two adult male macaques. This behavior demonstrates the existence of a persistent motivation to interact through a form of simulated grooming, as the animals were housed in adjacent enclosures separated by a glass panel preventing direct tactile contact. We find that such virtual grooming produces similar physiological sensations and social effects as allogrooming. We suggest that this behavior engages affective and reward brain circuits to the same extent as real social touch, and that this is probably achieved through high level processes similar to those involved in bodily illusions or synaesthetic phenomena previously described in humans. This observation reveals the unsuspected capacity of non-human primates to invent alternative, quasi-symbolic strategies to obtain effects similar to those provided by direct bodily interaction, which are so important for maintaining social bonds.

Concrete mixtures with photovoltaic panels glass: a review of the situation in Czech Republic

Solar energy production was initiated in the 1990s following by rapid increase of the use of photovoltaic (PV) technology. Most of older solar panels in the Czech Republic were installed between 2000 and 2006 and a global installed capacity of 222 GW was reached by the end of 2015. With the growing global PV market, a large amount of waste is expected to accumulate after 2030 which is associated with the new industry to process this waste, based on reduce, reuse, and recycle. This article summarizes findings and research conclusions regarding local issues collected by experts from the Czech Republic. Previous research showed that waste glass from photovoltaic panels can be used as a pozzolanic material in high-performance concrete, improving its properties. Further research on the use of waste from photovoltaic panels has been conducted in the Czech Republic since 2019 and the conclusions from various research confirm the suitability of using PV panel glass.

TRANSPARENT SOLAR PANELS

This article is about Transparent Solar Panels. Discusses current and future applications of Transparent Solar Panels. Here the pros and cons of Transparent solar panels are discussed. The different characteristics of transparent solar panels from conventional solar panels are discussed in detail. The replacement of window panes with solar panels is being discussed in the construction industry. Most importantly, information is given on the wide application of all these in the near future. In addition, this article extensively mentions the pros and cons of transparent solar panels. The article notes that transparent solar panels produce less electricity than conventional solar panels. This article compares the production costs of transparent solar panels and conventional window glass and conventional solar panels. Obviously, transparent solar panels are more expensive than window glass, but transparent solar panels are cheaper than conventional solar panels. Currently, these solar panels are not widely used. Because it was discovered very recently, but all this cannot stop the development of transparent solar panels. My main purpose in writing this article is to explain to people the importance of this discovery.

The Impact of Various Cockpit Display Interfaces on Novice Pilots' Mental Workload and Situational Awareness: A Comparative Study.

Future airspace is expected to become more congested with additional in-service cargo and commercial flights. Pilots will face additional burdens in such an environment, given the increasing number of factors that they must simultaneously consider while completing their work activities. Therefore, care and attention must be paid to the mental workload (MWL) experienced by operating pilots. If left unaddressed, a state of mental overload could affect the pilot's ability to complete his or her work activities in a safe and correct manner. This study examines the impact of two different cockpit display interfaces (CDIs), the Steam Gauge panel and the G1000 Glass panel, on novice pilots' MWL and situational awareness (SA) in a flight simulator-based setting. A combination of objective (EEG and HRV) and subjective (NASA-TLX) assessments is used to assess novice pilots' cognitive states during this study. Our results indicate that the gauge design of the CDI affects novice pilots' SA and MWL, with the G1000 Glass panel being more effective in reducing the MWL and improving SA compared with the Steam Gauge panel. The results of this study have implications for the design of future flight deck interfaces and the training of future pilots.

Static analysis of two-side supported 2-ply laminated glass panes through physics-informed neural networks

This paper utilizes an emerging machine learning technique, namely physics-informed neural networks (PINNs), to analyze the static mechanical behavior of two-side supported 2-ply laminated glass panes. The PINN model utilizes prior physical information in the form of partial differential equations during model training, eliminating the need for tremendous amounts of data required by traditional data-driven machine learning methods. The governing equations for the structural behavior of two-side supported 2-ply laminated glass panes are derived, based on which a PINN framework encompassing the neural network architecture and the loss functions is constructed. The training stability is evidently improved after the linearly inducing process, with the relative error maintained within a reasonable range. Extensive validation examples and case studies are provided to demonstrate the accuracy and effectiveness of the proposed method. Composite action analysis results reveal that below 70 % in the design is a conservative estimate for thinner laminated glass. Furthermore, the PINN method achieves exceptional computational efficiency, reducing computational times from six hours to just a few minutes for the uncertainty evaluation of laminated glass, indicating its potential in engineering practice.

Simplified structural analysis of laminated glass panels during fire exposure

Due to their high aesthetic value, energy-efficient properties, and contribution to daylighting, the demand for using glass panels in modern buildings has considerably increased over the past decades. However, ordinary glass panels are highly susceptible to cracking during a fire because of the temperature difference between the part of the glass exposed to the fire and the part protected by the frame. Damage to the glass can allow additional oxygen intake, leading to the flashover phenomenon significantly increasing fire severity. Laminated glass is superior to ordinary glass in its impact resistance, sound insulation, and ability to maintain post-breakage integrity. This paper provides a simplified method to study the effect of temperature gradients on the cracking behaviour of laminated glass panels. The temperature of the unprotected portion of the glass panel is first estimated by evaluating the mid-thickness temperature using the general heat transfer equation. Then, equations developed based on a parametric study that utilized ABAQUS are proposed to estimate the exposed and unexposed surface temperatures. This step was followed by evaluating the temperature of the protected glass portion. Subsequently, a method based on strain-equilibrium principles was developed to predict the corresponding maximum thermal stress. Comparisons with experimental and numerical work by others validated the proposed method.

Influence of Subcooling and pressure on flow boiling in a vertical mini-channel: Heat transfer analysis using inverse method

The background of this study is the problem of thermal runaway in the battery cells of electric vehicles. Increasingly powerful and compact battery packs require highly efficient thermal management. One potential solution is the direct liquid cooling of lithium-ion battery cells using a dielectric liquid which boils over a safety limit temperature. This approach intends to prevent in a first step the cell thermal runaway and if it fails in a second step its propagation to its neighbors: the liquid boiling helps to mitigate the cell temperature rise and to transport and spread the heat. The arrangement of the cells in the pack and their close spacing induce a scientific problem of convective boiling in a mini-channel. To enhance designs using this solution, a comprehensive understanding of flow boiling and a precise local heat transfer quantification is essential. The HFE-7100 has been selected as a working fluid for its attractive thermophysical properties and a suitable saturation temperature.The present paper introduces new experimental results of flow boiling dielectric fluid, the HFE-7100, in a vertical rectangular mini-channel. Measurements are carried out from start of boiling to dry-out. Boiling curves are obtained for a mass flux of 391 kg/(m².s), at different pressures (0.7, 1, 1.5 bar) and at different subcoolings (ΔTsub=0;15;30;45∘C). The test section is an aluminum block instrumented with three lines of five K-type thermocouples located all along the flow. The visualization of the flow is achieved through a glass pane with a high-speed camera to identify different flow patterns. The local heat transfer coefficient is calculated by a resolution of a 2D inverse heat conduction method.The experiment mainly aims at determining the heat transfer coefficient, the critical heat flux (CHF) and the pressure drop and at characterizing both the flow regimes and the dry-out phenomenon. The influence of subcooling and pressure on flow boiling is analyzed. An increase in subcooling enhances the CHF and the heat transfer coefficient, and delays the dry-out. Subcooling has an impact on the flow pattern and modifies the type of CHF. In the operating conditions tested, a decrease in pressure enhances CHF and delays dry-out. On the other hand, the heat transfer coefficient increases with rising pressure. Similarly, pressure drops are lower with higher pressure.

Advancing solar distillation efficiency through calcium hydroxide coating and enhanced configuration of mirror-assisted system

While solar distillation presents an eco-friendly and sustainable means of obtaining potable water, its capacity to generate water is relatively modest. The principal objective of this research endeavor resides in the enhancement of the condensation mechanism within solar distillation apparatuses, concurrently ameliorating thermal losses from the distiller's rear wall (MSS). This enhancement is achieved through the strategic application of a calcium hydroxide coating onto the rear surface of back wall of conventional solar still (CSS). This study investigated the performance of the solar still painted by five distinct binder material ratios (10 %, 20 %, 30 %, 40 %, and 50 % by weight) relative to the calcium hydroxide component. Additionally, the application of the calcium hydroxide paint on the rear wall was tested with and without a protective glass panel. Finally, incorporation of mirrors in conjunction with a protective glass panel preceding the paint application was investigated. The experimental observations have led to a significant insight: a binder ratio of 20 % yields optimal adhesive qualities while concurrently upholding cohesion strength. The MSS with glass plate and mirrors exhibited the most impressive performance, with a yield rise of 130 % and an efficiency of 53.5 %. The costs of freshwater of CSS and MSS were 0.02 and 0.015 $/L.

Experimental and numerical study of the interaction between tempered glass fallout and enclosure fire dynamics

Tempered glass, as an important type of safety glazing, is extensively used in high-rise buildings. However, little is known about the fallout behavior of tempered glass in the compartment with different fire locations. Therefore, in this work, the exposed framed glass panes with the dimension of 815 × 815 × 6 mm3 were heated by a pool fire in the compartment. The fuel pans were placed at six different locations in the compartment. It was found that the fallout time of tempered glass increased with a decrease in the distance between the fuel pan and glass panes; when the fire was moved to the wall side, the fallout time of tempered glass was longer. Besides, the temperature gradient of the glass surface at the exposed area was insignificant when the fire source was at the center line of the doorway opening, while there was an evident temperature gradient of the glass surface on the height direction due to the apparent smoke layer in the upper of the compartment for near wall fire locations. In addition, CFD numerical simulations were conducted using FDS software to observe the temperature and velocity fields inside the compartment with different fire locations. It was found that when the fire was moved to the wall side, the circulation flow was formed at both the high-temperature region near the fire source and the low-temperature region on the left of the compartment.

Energy assessment of a sliding window integrated with PV cell and multiple PCMs

Windows often serve as a thermal weak point between a room's interior and the outside world. As such, we are exploring a new design for a sliding window that integrates both multiple phase change materials (PCMs) and photovoltaic (PV) cells. During the day, the PV cells produce electricity, which can be used in the building during the night. The sliding mechanism introduces several innovative features: use the PV-PCM glass unit (as the external sliding layer) or a standard glass unit (the internal sliding component). The PV-PCM window also can be used as a sliding light shutter or curtain. The PV cell in the proposed design is operated in the closed and open case due to the sliding design. We compared the thermal performance of a single PCM type (either RT-35or RT-27) with a combination of multiple PCMs (RT-35-RT27). Further, we evaluated various thickness combinations of the multi-PCM configuration (RT-35-RT27), including 2.5mm–7.5mm, 5 mm–5 mm, and 7.5 mm–2.5 mm, to identify the best-performing setup. Over the course of a day, the multi-PCM setup (RT-35-RT27) maintains a consistently lower average interior wall temperature than using a single PCM. Among the configurations tested, the 5 mm–5 mm multi-PCM setup (RT-35-RT27) emerged as the most effective, displaying steadier results than the other variations. Compared to a standard single glass pane, the proposed PV-PCM window reduced the highest interior wall temperature by up to 46 % when employing multiple PCMs. As a result, we advocate for the adoption of this innovative sliding window in future building designs.

Blast performance of point-supported laminated glass panes with non-rigid supports

According to the current state-of-practice, point-supported glazing systems can be supported by different structures with varying levels of flexibility. This paper presents results from numerical studies on the blast performance of frameless, point-supported Laminated Glass (LG) panes, with special consideration of the effects of support flexibility on the blast performance of the panes. Capacity Pressure-Duration (P-D) curves, maximum reaction forces, and maximum displacements of point-supported LG panes are derived for 36 unique point-supported LG panes subjected to nearly 80 different blast scenarios and evaluated at four limit states ranging from initial cracking to ultimate failure. Obtained results indicate that, generally, as the support stiffness decreases, initial cracking capacity of the point-supported LG panes increases. However, this is not the case in other limit states. For example, in the case of ultimate failure performance criteria, support flexibility has detrimental effects; as the support stiffness decreases, ultimate capacity of the point-supported LG panes also decreases. Therefore, neglecting the support flexibility is not necessarily a conservative assumption. This affirms the importance of considering support flexibility in the design of blast resistant glazing systems. Additionally, under the same blast loading, as the support stiffness decreases, the maximum support reaction tends to decrease and the maximum displacement of the pane tends to increase. It is important to note that these correlations may not agree in design cases targeting specific limit states.

The Influence of Strain Rate Behavior on Laminated Glass Interlayer Types for Cured and Uncured Polymers.

Recent explosions and impact events have highlighted the exposure of civil structures, prompting the need for resilient new constructions and retrofitting of existing ones. Laminated glass panels, particularly in glazed facades, are increasingly used to enhance blast resistance. However, the understanding of glass fragments and their interaction with the interlayer is still incomplete. This paper investigates experimentally the quasi-static and dynamic responses of cured and uncured polymers for seven different materials-two different products of polyvinyl butyral (PVB), two ethylene vinyl acetate products (EVA), one product of thermoplastic polyurethane (TPU), and two SentryGlas products (SG)-that were tested between 21 and 32 °C (69.8 and 89.6 °F), which is the recommended room temperature. In these experiments, the responses of PVB, EVA, TPU, and SG were evaluated under a quasi-static strain rate of 0.033 s-1 and compared to the results under a relatively higher strain rate of 2 s-1. Moreover, the high strain rate loading of the materials was accomplished using a drop-weight testing appliance to evaluate the engineering stress-strain response under strain rates between 20 and 50 s-1. The results demonstrated that with strain rates of 20 s-1, PVB behaved like a material with viscoelastic characteristics, but at 45 s-1 strain rates, PVB became a non-elastic material. SG, on the other hand, offered both a high stiffness and a high level of transparency, making it a very good alternative to PVB in structural applications. In contrast, after the maximum stress point, the response to the failure of the seven materials differed significantly. The tests provided ample information for evaluating alternative approaches to modeling these different materials in blast events.

Case study: Computer modeling the noise produced by a future food court radiated to nearby existing offices

Lately, there’s an increase in the co-existence of spaces of different usage with acoustical challenge. Throughout 2016 to 2018, the 2nd floor of the Complexe Les Ailes, in Montreal, underwent a fit-out to become a food court. At its center, there is an elliptical atrium where all levels are can be viewed. There are existing offices above the food court separated by a glass pane. The purpose of this study was to evaluate the noise generated by human activities in the future food court to the adjacent offices and recommend noise control elements if needed. Multiple sound samples were taken at existing food courts to quantify the sound level. Simulations were done with ODEON, a room acoustic software, to evaluate the sound level produced by different activities. On-site measurements were conducted to calibrate the existing conditions with the 3D ODEON model. Finally, noise reduction tests were undertaken to determine the sound levels that would be radiated in the offices by the activities in the food court. To reduce noise disturbance in the offices, acoustical treatment under the ceiling of the food court was recommended and the 3rd and 4th floor glass panes composition would have to be improved.