Glass Panels Research Articles

Development of Titanium Dioxide Coating for Self-Cleaning Photovoltaic Panels

Amid escalating global energy demands and environmental concerns, the transition to renewable sources like solar power is imperative. Despite the advancements in photovoltaic (PV) technology promising increased efficiency, soiling on PV panels—composed of dust, bird droppings, and contaminants—poses a significant challenge, obstructing sunlight and reducing energy conversion efficiency. Building upon existing research on titanium dioxide (TiO2) nanoparticle coatings, our study investigates their super-hydrophilic and anti-soiling characteristics to enhance self-cleaning capabilities in solar applications. Furthermore, our research investigates the application of (3-aminopropyl)trimethoxy silane as an interlayer to reinforce the adherence of the TiO2 coating to PV panel glass, thereby enhancing its durability. Preliminary results highlight the coating’s exceptional super-hydrophilic properties, with water contact angle measurements less than 10°, indicative of TiO2’s strong water affinity. Spectrophotometer measurements show that the developed coating maintains high optical transmittances for the wavelength range from 350 to 800 nm, which is the most crucial factor for energy conversion in solar panels. Our contributions aim to advance solar energy technologies and support the shift towards more sustainable energy solutions, highlighting the role of innovative materials science in addressing solar power’s operational challenges.

LCV Vehicle in-cab noise prediction and reduction using SEA based simulation approach

With increase in consumer demand vehicle OEMs are developing quieter vehicles at a design stage using acoustic simulation tools to reduce development cycle times avoiding costly proto builds and test iterations. Present work describes application of statistical energy analysis (SEA) simulation approach for in cab noise prediction and noise reduction through sound package optimization for LCV vehicle. In first step complete vehicle in-cab SEA model is prepared with baseline sound package concept. It consists of comprehensive definition of structural panels, interior and exterior cavities. Noise control treatment is modelled as multi-layer poro-elastic materials. Airborne noise excitations for sources engine, transmission, intake and exhaust muffler are applied. Source strengths for above sources were derived from dyno-coupled powertrain noise tests in the anechoic chamber. Load case of rated speed was considered neglecting tire and wind noise during simulation. Contribution analysis was carried out to find out sensitivity of different panels on interior noise at various frequencies. It was observed that bottom middle floor panel and rear glass panel were major noise contributors. Noise mitigation was carried out by optimizing floor panel sound package and intake air filter within given space constraints. These modifications resulted in overall 2 dB in-cab noise reduction

Enhancing building energy efficiency: Innovations in glazing systems utilizing solid-solid phase change materials

This study investigates the energy efficiency of a double-glazing window (DGW) integrating a solid–solid phase change material (SSPCM) with limited thickness, applied to the inner glass pane within the air gap. Numerical model, validated against experimental data, is developed using a finite volume method in ANSYS Fluent. In this model, the Discrete Ordinates (DO) model is applied to simulate radiation, while the enthalpy-porosity approach is used to capture the solidification and melting processes in the phase change material. With this model, the energy performance of the system is analyzed under various transient temperature values (10 to 30 °C) and ranges (1 to 5 °C) during the coldest and hottest days of the year, as well as during cloudy and sunny days in Montreal (Dfb), Vancouver (Cfb), and Miami (Aw). According to the obtained results in Montreal, the DGW-SSPCM system consistently saves energy under summer sunny conditions, with optimal performance when the SSPCM remains transparent. However, it incurs energy losses in cloudy days, where the energy lost is 2.3 times greater than the energy saved in sunny days. In Vancouver, the system shows consistent energy savings, particularly at Tc = 30 °C, with average savings of 20.5 kJ (23 %) under summer sunny conditions. The system is most beneficial in Vancouver, where winter energy savings in cloudy days (50.6 kJ) are 7.1 times greater than the losses in sunny days (7.1 kJ). In Miami, the system results in energy losses by 60 % and 5 % (at Tc = 30 °C) under both summer sunny and cloudy conditions, respectively, indicating unsuitability for its climate. During winter sunny conditions, all three cities experience energy losses, with Vancouver showing the lowest of 7.1 kJ (3 %) and Montreal the highest of 64.4 kJ (19 %) at Tc = 30 °C. In winter cloudy conditions, the system saves energy in all cities, with the highest savings in Miami of 54.5 kJ (26 %) at Tc = 30 °C. Overall, the SSPCM-DGW system has proven to be beneficial in Vancouver across various conditions in terms of energy and visual performance. These findings highlight the necessity of considering localized climate factors when designing and implementing energy-efficient glazing systems. Finally, the SSPCM-DGW system has provided complete visual clarity during office hours, making it more suitable for commercial buildings.

Life Cycle Assessment of Construction Components of Schools in Southern Brazil

Introducing energy efficiency techniques in schools can significantly reduce energy consumption, as Brazil has a large public education system. The main objective of this work was to select the set of construction components with the lowest environmental impact for use in schools in Florianópolis, southern Brazil, through life cycle assessment (LCA). Two types of walls, four types of roofs, and two types of window frames were studied. Ceramic bricks measuring 14x9x19cm and 9x19x19cm were considered for the walls. Wood and aluminium were used for the window frames, with single glass panes on all windows. For the roofs, fibre cement tiles with a PVC ceiling, a drywall ceiling, and a concrete slab were considered, as well as ceramic tiles with a PVC ceiling. Computer simulations were conducted using the EnergyPlus program in order to determine the building’s energy consumption. SimaPro was used to run the LCA. The construction of the building and one year of its energy consumption were analysed to select the combination of components with the lowest impact on the building’s life cycle. Finally, the set consisting of 9x19x19cm ceramic brick walls, wooden frames, and roof with fibre cement tiles and PVC ceiling presented the lowest environmental impact. Keywords: Life Cycle Assessment; public schools; computer simulation; buildings; EnergyPlus; SimaPro

Numerical and experimental blast response of multilayer laminated glass panels

Laminated glass is used in high-security buildings to mitigate the effects of blasts and ballistic loadings. The multi-layered composition of the laminated glass (LG) panels allows the glass panes to crack and undergo large deflections while preventing glass shards from spalling by mostly remaining attached to the polymeric interlayer. To characterize multilayer LG panels under blast loading, it is essential to develop their static resistance response under uniform loading. A full-scale water chamber was used to experimentally evaluate the quasistatic response to the failure of the multilayer LG panel systems under uniform pressure. The influence of different polymeric interlayer types on the response of multilayer LG panels was studied. Also, the glass breakage patterns and deflections exhibited by various multilayer glass configurations were investigated. The response of LG panels under blast was developed using ANSYS AUTODYN, which was verified using field experiments. LG panels with an Ethylene Vinyl Acetate (EVA) polymeric interlayer experienced the most dynamic deflections, whereas LG panels with an ionoplast SentryGlas® (SG) polymeric interlayer displayed the least dynamic deflections. The results indicated that multilayer LG systems provide higher blast resistance compared to double-layer systems; the additional layers can help reduce glass breakage and maintain structural integrity. Multilayer LG system’s SG interlayer enhanced blast protection by allowing load transfer and ensuring uniform load distribution between glass layers.

Glass serviceability limits: new evidence from human-centred studies

AbstractThe performance of the building envelope is crucial for minimizing operational carbon emissions of buildings and maintaining indoor comfort. Contemporary building envelopes, such as engineered glazed façades, achieve high performance levels but often add a significant amount of embodied carbon. There is therefore an incentive to reduce the thickness of the glass panels, but the minimum thickness possible is often not governed by strength or manufacturing limits but rather by the deflection (serviceability) limits. Despite objective criteria guiding serviceability limits, user acceptance of deformation remains unexplored, leading to conservative designs. This paper introduces a novel method for measuring user satisfaction with glass deformations, aiming to establish acceptance thresholds comparable to objective criteria. The study involves a novel experimental campaign to assess volunteers' levels of perception and acceptance of various glass deformations. The glass was deformed using a bespoke electro-pneumatic system at levels corresponding to below, above, and at the current serviceability limit. The results demonstrate the feasibility of measuring human responses to deformations in the glazing and provide essential data for setting serviceability limits. The experiments and corresponding user satisfaction feedback indicate that the current serviceability limit of L/50, may be relaxed, thereby presenting opportunities for material efficiency, such as the adoption of thinner glass in facades. The methodology effectively captures human responses, revealing that changes in reflection were the primary reason for the perception of movement; leading to a higher perception of glazing movement and a lower acceptance at night. Overall, participants felt safe regardless of their prior knowledge on glass properties, and providing this information to participants did not improve acceptance, which was already sufficiently high. The findings from this research fill an important knowledge gap in understanding user acceptance of glass deformations, crucial for comprehensive user satisfaction assessments and evidence-based reductions in glazing thickness.

Experimental investigation of the compressive and shear resistance of laminated steel-reinforced glass beams

This paper presents an experimental investigation into the compressive and shear resistance of triple-layered laminated steel-reinforced glass beams. Two types of tests are performed: (a) local compressive tests (force over a support) and (b) bending tests (force close to a support). In total, six local compressive tests and eight bending tests are performed. Overall, beams with a shear span-to-effective depth ratio (a/d) approximately equal to 0, 0.63, and 1.0 are tested. Two different types of flexural reinforcement are used separately: solid (S) and hollow (H) reinforcement. The behaviour of the outer glass panes, and top and bottom reinforcement is monitored using strain gauges and Digital Image Correlation (DIC). The test results are elaborated in terms of load-displacement curves, the evolution of strains and crack patterns. Three failure modes are observed: yielding of the reinforcement (PF), crushing of glass (CF), and rupture of the reinforcement (RR). Shear failure occurred due to the crushing of glass in the compressed diagonal strut in the shear span. It was found that the shear resistance increases with a smaller shear span-to-effective depth ratio and stronger reinforcement. The dominant shear transfer mechanism was the direct strut action. It was found that the post-fracture capacity had a relatively constant value for all the tests with a slight increase for smaller a/d. The actual tensile strains in the bottom reinforcement measured by DIC are compared with the calculated strains based on the curvature of uncracked and cracked cross-sections, assuming plane section behaviour. It was observed that the actual strains are systematically larger than the calculated ones because, in reality, the section does not remain plane. After the appearance of the first crack, the beams essentially behave like strut-and-tie systems, where the strut is the diagonally compressed laminated glass and the tie is the bottom reinforcement.

On the lightweight design of laminated insulating glass units in cruise ships

ABSTRACT Modern cruise ships employ many large windows to enable passengers to enjoy the marine environment. Most windows are insulating glass units (IGUs) consisting of laminated glass and a hermetically sealed cavity. These laminated IGUs exhibit three physical effects under bending: (1) geometric nonlinearity of the glass panes, (2) shear transfer in the laminated glass, and (3) load sharing due to the hermetically sealed cavity. The Authors have previously studied the (1) and (3) effects on the window mechanical behaviour and glass pane thickness determination. Hence, this paper investigates through optimisation how all these effects together lighten the IGUs, and how the shear transfer affects the IGU mechanical behaviour with the optimised thicknesses. All three combined effects have positive effects on the IGU weight. These results are more pronounced for large and thin IGUs subjected to high design loads. For example, the choice of interlayer material is less important (for optimum weight) for small windows subjected to a low design load. Since all the effects are important, using the finite element method is recommended to achieve a lightweight window design.

Assessing the sustainability of solar photovoltaics: the case of glass–glass and standard panels manufactured in Lithuania

Assessing the sustainability of solar photovoltaics: the case of glass–glass and standard panels manufactured in Lithuania

Pilot Federated Analysis Projects

The Cambrian explosion of Trusted Research Environments (TREs) will inevitably lead to increased data siloing and potentially decrease achievable data science. Federated access to data is a mitigation against this risk. The presentation will cover two major infrastructure demonstrator projects to address this need and start the UK journey towards interconnected TRE’s. TELEPORT was an infrastructure to connect TREs and allow all the data assets to be seen through a single pane of glass while leaving them in situ; the analysis can be performed on each data asset, as well as combining data from multiple TREs to derive knowledge. The analysis is performed within the construct of a pop-up TRE, which is a temporary project-specific TRE. The data governance model is operated in an as-is state, with all egress controls being applied upon extraction of research output. This method has been termed Federated Data. TREFX is a set of infrastructure based around international GA4GH standards and the RO-CRATE concept to provide a platform to send complex workflows to the TRE’s to be performed upon the data assets, with the output post egress checking to be re-packed into the inbound RO-CRATE prior to being returned to the researcher. This method addresses both federated analysis and method reproducibility. This project was extended to cover ADDI workloads for dementia. Both solutions were jointly developed by Swansea University / SeRP and share common elements. Future work will see both these products being combined into a hybrid approach as well as spin-out products and services.

RESEARCH OF THE DESTRUCTION CONDITIONS OF GLAZING OF ENCLOSING STRUCTURES UNDER THE CONDITIONS OF THERMAL INFLUENCE OF FIRE

The article presents the main results of mathematical modelling of the destruction of glazing of enclosing building structures with translucent elements under fire conditions. The authors analyse literature data on calculating the fire resistance of enclosing building structures with glazing. The results show that improving methods for predicting the fire resistance of glazing is relevant. Mathematical models for the numerical study of the behaviour of glazing under the thermal influence of the standard fire temperature regime are substantiated. Mathematical models of the heat transfer process involve using a non-stationary differential equation of heat conduction with boundary conditions of the third kind, accounting for the convective and radiant heat exchange between the air in the room with the fire and the glazing. As a criterion for the destruction of glazing under the influence of fire, the authors establish the temperature resistance parameter, which is determined based on the mechanical characteristics of the glass. The article highlights the relevant data on the study of temperature indicators and the mechanism of glazing failure, using mathematical modelling with well-founded mathematical models. It obtains the results of the thermal calculation by applying the finite difference method for solving the non-stationary differential equation of thermal conductivity. The methodology for determining the time of glazing failure under the influence of the standard temperature regime of a fire using the calculation parameters obtained based on well-founded mathematical models is substantiated. An analysis of the adequacy of the obtained calculation data was carried out by comparing them with the results of experimental studies using statistical criteria. As a result of the analysis, the authors confirmed the validity of the calculation data. A complete factorial experiment was conducted based on well-founded mathematical models, which revealed the regularities of the dependence of the parameters of thermomechanical processes in single-layer glass on its structural characteristics. The revealed regularities have the form of linear regression dependences of the destruction time on the thickness of the glazing and the maximum length of the glass panel without bars. Using the regularities of the dependence of the parameters of thermomechanical processes in single-layer glazing on its structural characteristics, the authors constructed reference tables for evaluating the fire resistance of enclosing structures with glazing. The research obtained new scientific data on the study of the behaviour of glazing of enclosing building structures under the thermal influence of fire through mathematical modelling, which is the basis for improving the methods of calculating the fire resistance of enclosing structures with translucent elements. Keywords: enclosing building structures, glazing, fire resistance limit, calculation method, glass heat resistance.

Assessment of cantilevered curtain wall system supported by tension rods for an enclosed circular building

Curtain wall systems have undergone significant advancements to meet the evolving architectural requirements and achieve aesthetic appeal and functionality in buildings worldwide. These non-structural enclosures, typically constructed with lightweight materials like glass or metal panels, contribute to the visual appeal of high-rise structures while providing numerous benefits, such as ample natural light and unobstructed views. The current paper focuses on analyzing and designing a cantilevered curtain wall system supported by tension rods for the auditorium façade at a simulation centre. The curtain wall surrounds the entire primary structure of the building, which has a circular layout. The study uses numerical modeling with the Robot software to analyze stresses and deflections in the glass, tension rods, mullions, and transoms while considering a wind load of 1.6 kPa. According to the findings, tempered laminated glass that is 19.52 mm thick satisfies the Ultimate Limit States (ULS) and Serviceability Limit States (SLS). Under the limit states, the Technal system (FM169) reinforced with steel tubes can transfer the design loads. The steel framing system that supports the tension rods and transfers the load of the curtain wall to the main structure is likewise considered safe. The structural integrity of the curtain wall is ensured by the prescribed requirements for the connections, which include a 5 mm fillet weld with a throat thickness of 3.5 mm, 20 mm diameter tension rod (Kin long system), and 8 mm thick MS plates with channel brackets. This research expands the practical application of cantilevered curtain wall systems of buildings with enclosed circular layouts.

Reuse and remanufacturing of insulated glass units

AbstractMany office and residential buildings in Europe need to be renovated in the near future to meet current energy efficiency requirements. This often comes down to updating the insulation performance of the building envelope including the windows. Most “old” windows consist of a frame and a double insulated glass unit (IGU) or even monolithic glass panes – typically without any low-e coating. These non-coated double glazings have a Ug-value of 2.7 W/m2K (single glazing even 5.2 W/m2K). Modern coated triple glazed IGUs provide Ug-values of up to 0.5 W/m2K.This paper deals with the question of how old insulating glass units can be re manufactured to match the state of the art in terms of the energy efficiency. For this purpose, dismounted IGUs from the 1980s are used. After analyzing the remaining functionality, the double IGUs are disassembled. The single glass pane is cleaned, and the old edge sealing is removed. The old glass pane is combined with a new coated low-e glass and a spacer system to form a new upgraded IGU with warm edge technology. This study demonstrates that remanufactured IGUs can achieve the performance of IGUs made from new glass.

Experimental analysis of the synergistic impact of fan and nocturnal thermal insulation on enhancing the thermal performance of latent-energy-storage solar air collectors

Solar air collectors equipped with energy storage functionality are widely utilized to address the mismatch between heat demand and supply periods during winter, effectively facilitating heating needs. However, phase change energy storage flat plate solar air collectors are hindered by inefficiencies, primarily due to the low rate of convective heat transfer and substantial nocturnal energy losses, which considerably undermine the overall energy efficiency of these collectors. In response to these challenges, a forced convection approach utilizing a fan was adopted to augment the convective heat transfer rate, and insulation was applied to glass panes overnight to curb energy wastage. Two solar air collector systems were constructed and examined: a natural convection-based energy storage solar air collector (NCSAC-PCM) and another solar air collector incorporating forced convection with nocturnal thermal insulation (FCSAC-PCM-NTI). Comparative experiments revealed that the combination of forced convection with nighttime insulation in the latter design led to an elevation in the mean indoor temperature by 1.4 °C, alongside a decrease in the temperature gradient variation within the space during the test period. Furthermore, this integration significantly enhanced the energy efficiency by 53.71 % and the exergy efficiency by 11.45 %.

Fast fracture in toughened glass when impacted randomly by Ice

Modelling the triggering of fracture at a pre-existing flaw is an evolving method of predicting ultimate failure in glass. This fracture mechanics approach of modelling has been shown to give more reliable predictions than a calibrated probabilistic distribution model (as is commonly adopted) when dealing with hail impact which is highly transient in nature. The dynamic stress intensity factor controlling fast crack growth is sensitive to the complex stress state surrounding the critical flaw. Finite element simulations of localised stresses in 3D could incur high computation cost which is compounded by the need to repeat computations until convergence and to simulate multiple strikes in emulating a storm scenario. In this study, closed-form expressions were developed to waive away the need of any simulations. With hail impact, boundary conditions of the glass panel need not be factored into the modelling, as the highly transient stresses are wave controlled. Input parameters are the thickness and level of prestress in glass; offset of position of strike from the known crack and its depth; and the size, velocity, and temperature of the ice impactor. Results from 40 test scenarios involving 5 offset distances, 3 crack depths, 2 glass thicknesses, and 2 sizes of ice were used to validate the prediction, and to reveal the sensitivity of the outcome of the impact to changes in the impact position relative to the known crack.

Scratch-induced micro-fracture behaviour and translational failure of glass: An experimental and numerical study

The structural safety of aged glass members shows significant sensitivity to surface scratches. The distribution and geometrical features of scratch impacts the glass fracturing. In this study, the fracture behaviour of scratched thin glass pane was investigated by the ordinary state-based peridynamic (OSB-PD) theory. Coaxial double ring test was first conducted to identify the mechanical and fracture behaviour of scratched glass plates that serve as the benchmark. The applicability of simplifying and reconstructing the actual scratches in numerical models was then examined. The refined three-dimensional fracture process from micro-crack coalescence to macro-propagation of featured cracks can be well described by the developed PD model. The propagation of in-plane radial cracks was found prior to median cracks along the thickness for scratched glass. Crack branch was observed due to shallow scratch depth and the primary crack branching point lies near the edge of the scratch. The transition from scratch-induced failure to strength-induced failure due to particular scratch spatial location was also tackled, which benefits the accurate performance assessment of scratched glass.

Laboratory and field validation of the performance benefits and costs of thin triple-pane windows in residential buildings

The adoption of high-performance triple-pane windows that significantly reduce heat transfer has been slow, in part because they are thicker, heavier, and more costly than double-pane windows. One path to increase adoption of triple-pane windows is to replace the conventional double-glazing insulated glass unit (IGU) with a modified triple-glazing design that uses a very thin central pane of glass. This thinner triple-pane IGU can then be “dropped in” to the double-pane IGU pocket without requiring major modifications to frame design. The Department of Energy sponsored laboratory and field testing of thin triple-pane windows by Pacific Northwest National Laboratory. This article presents findings from both the Lab Homes study and subsequent field demonstrations carried out over a 3-year period (2020–2023). The laboratory and field studies demonstrated the manufacturing and distribution feasibility of thin triple-pane windows, successfully installed at multiple sites, using double-pane frames from four different manufacturers and thin triple-pane IGUs from two different manufacturers. Compared to a home with double-pane, clear-glass windows, testing demonstrated average whole-home heating energy savings of 12% and cooling energy savings of 27% for thin triple-pane windows. Improvements in comfort, sound insulation, and condensation potential were noted in both laboratory and field studies.

Mechanical Stability of PV Modules

A significant increase in reported glass breakages from the field was recognized during the past three years, where a disproportionately high number of modules were affected by glass breakage. Different substructures and module designs are affected, framed and unframed modules, tracked and fixed systems. What all inquiries have in common, however, is that modules with a double-glazed design with ≤ 2.5 mm glass thicknesses are affected and the problems were observed after just a few months in field operation. Various factors such as heavy weather events, faulty installation or errors in the structural design could be excluded as root causes and our experience points on additional, more fundamental problems that are associated in particular with the continuing trend towards larger modules > 3 m2 and thinner module glass ≤ 2mm. Furthermore, it seems that the residual compressive surface stress of the glass as one major parameter that determines the stability of glass panes has not been considered in this context in the PV module industry yet. In this work, we focus on the glass thickness in combination with the compressive surface stress. Besides qualitative methods, one possibility to investigate the surface stress quantitatively is a scattered light polariscope (SCALP), previously used in the glass industry. In particular, the aim is to validate the SCALP measurement method for the use on PV modules. Furthermore, a potential correlation between the surface compressive stress and the mechanical stability of various common module designs with 2 mm and 1.6 mm glass is investigated.

Sustainable repurpose of end-of-life fiber reinforced polymer composites: A new circular pedestrian bridge concept

In response to global challenges in resource supply, many industries are adopting the principles of the Circular Economy (CE) to improve their resource acquisition strategies. This paper introduces an innovative approach to address the environmental impact of waste Glass Fiber Reinforced-Polymer (GFRP) pipes and panels by repurposing them to manufacture structural components for new bicycle and pedestrian bridges. The study covers the entire process, including conceptualization, analysis, design, and testing of a deck system, with a focus on the manufacturing process for a 7-m-long prototype bridge. The study shows promising results in the concept of a sandwich structure utilizing discarded GFRP pipes and panels, which has the flexibility to account for variabilities in dimensions of incoming products while still meeting mechanical requirements. The LCA analysis shows that the transportation of materials is the governing contributing factor. It was concluded that further development of this concept should be accompanied by a business model that considers the importance of the contributions from the whole value chain.

Embedded real-time ultrasound-based multi-touch system.

In this paper, an active ultrasound-based touchscreen technology is presented for real-time monitoring of multiple contacts on a glass panel of 20 × 19 cm. Both fundamental Lamb wave modes are generated by sending a linear chirp between 50 and 100 kHz to a single piezoelectric ceramic lead zirconate titanate. Measurement is performed using four piezoelectric ceramic lead zirconate titanate elements, and real-time localization and detection are performed on a system on module i.MX 8 M Nano. Results show that Lamb waves can be used for real-time multi-touch detection and localization on both sides of the panel. Moreover, the prototype developed allows for relative pressure measurement.