Characteristics Of Panels Research Articles

Effect of width on the fire spreading characteristics of PE metal sandwich panels under the action of double fire sources

The exterior walls of high-rise buildings typically contain substantial thermal insulation materials. Once ignited, these materials can readily induce major fire accidents. In this study, through the constructed reduced-size experimental bench to evaluate the effect of window overflow fire and upper chamber fire on the fire spreading properties of PE metal sandwich panels with different widths. The result shows that the average flame height and flame oscillation intensity increased with an increase in fire source power and sandwich panel width. Temperature curves exhibited a consistent trend under different working conditions. Dimensionless analysis of the sandwich layer temperature indicated that under specific fire source power conditions, the 60 cm sandwich panel reached the highest peak temperature and posed the greatest fire hazard. Based on the width and length of the preheating zone, a model for the rate of flame spreading was created. At a constant sample width, the accelerated spread of the upper part of the plate by the action of fire source B was more obvious. These conclusions are instructive for the study of building facade fire.

Optimizing urban energy management: A strategic examination of smart grids and policy regulations

This research addresses the critical challenges in urban energy management, focusing on load forecasting and optimizing renewable energy sources considering policy regulation. A novel Hybrid Long Short-Term Memory-Artificial Neural Network (LSTM-ANN) learning technique is proposed for accurate load and renewable energy output power forecasting. The hybrid model leverages the strengths of LSTM and ANN, providing a robust solution for capturing temporal dependencies and complex patterns in the data. Additionally, the Bee Algorithm for Optimization (BAO) is employed to handle the nonlinearity and nonconvexity inherent in energy management problems. BAO optimally schedules the operation of various generation units, considering the diverse characteristics of gas turbines, photovoltaic panels, and wind turbines. The effectiveness of the proposed hybrid model and optimization algorithm is demonstrated through comprehensive comparisons, showcasing superior accuracy and convergence speed compared to traditional methods. This research contributes to the advancement of intelligent energy management systems, offering a reliable framework for optimizing renewable energy utilization in real-world applications.

Self fuzzy-genetic approach for boosting photovoltaic efficiency

The generation of power in Photovoltaic systems is reduced when they operate far from their maximum power point. For optimal operation, it is essential to continuously track the maximum power point of the PV solar array. However, identifying the maximum power point is a challenge due to the nonlinear relationship of electrical characteristics of PV panels with external factors. To address this issue, we present a novel design approach for a self-organizing, self-tuning fuzzy logic controller, applied to the problem of maximum power point tracking in photovoltaic systems. We outline the basic structure of the fuzzy logic controller and address the design problems typically associated with conventional trial-and-error schemes. We also discuss the suitability of the genetic algorithm optimization technique for determining and optimizing the fuzzy logic controller design. In our proposed approach, we translate the normalization factors, membership function parameters, and controller policy into bit-strings, which are then processed by the genetic algorithm to find a near-optimal solution. To achieve high dynamic performance, we choose a particular objective function as a performance index. We compare our approach with two variants of the maximum power point algorithm, one based on genetic algorithms and the other based on fuzzy logic, as well as with the methods described in references [34] and [35], in order to evaluate its effectiveness.

Photosvaltable Characteristics Monitoring System Using the Internet of Things (IOT)


 
 
 
 Continuous monitoring of solar panel performance is essential to ensure effective and efficient generation of electrical energy. Developing a monitoring system such as an I-V characteristic curve tracker enables real-time monitoring and identification of potential problems or efficiency improvements. The system utilizes a circuit switching system for accurate and continuous measurement, providing insight into how the solar panel responds to changing environmental and load conditions. The data recorded by temperature, light intensity, current, and voltage sensors on the solar panel provides valuable information about its condition and the environmental factors affecting it. Utilizing IoT technology allows real-time monitoring of the data, accessible via a web page and presented graphically. The data is also stored in Excel format for further analysis, so users can access and monitor continuously as long as they are connected to the internet. From the experimental results, the Voc of the solar panel ranged from 18.7 V to 20.42 V, and Isc between 0.0727 A to 0.2145 A, which were tested under solar irradiation ranging from 100 to 500 W/m². This research demonstrates the importance of continuous monitoring and the effectiveness of the developed monitoring system in providing real-time data for analysis and optimization of solar panel performance. The system has been tested to meet the IEC No. 13B-23 standard for accuracy classes 0.2 and 0.5. A comparison between manual testing and sensor testing shows that despite the difference in accuracy levels, the sensor measurements have a relatively low average error (1.04% for voltage and 0.64% for current) compared to manual measurements, indicating that the sensor is reliable in providing accurate data. This demonstrates the reliability and effectiveness of using the sensor in the solar panel characteristics monitoring system.
 
 
 

Thermo-Environmental Performance of Modular Building Envelope Panel Technologies: A Focused Review

Modular construction is becoming famous for buildings because it allows a high degree of prefabrication, with individual modules easily transported and installed. Building envelope optimization is vital as it protects buildings from undesirable external environments by expressly preventing the incursion of outside elements. This research uses a systematic literature review to appraise the characteristics of modular envelope panels, focusing on hygrothermal and energy performance. A total of 265 articles were subjected to rigorous filtering and screening measures. The findings reveal notable inconsistencies in modular envelope terminologies and a lack of consistent performance measures, which present significant challenges for research and development efforts. Furthermore, the results indicate a predominant focus on hygrothermal and energy performance in existing studies, with limited attention to environmental impacts and other performance factors. Moreover, the existing literature primarily addresses modular envelope solutions in temperate climates, offering inadequate information for hot and hot–humid climate contexts. To address these gaps, this study proposes categorizing modular envelope panels into four distinct categories: active, passive, smart, and green/vegetated wall panels. These findings will benefit researchers, architects, building envelope designers, policymakers, and organizations developing building performance-related assessment ratings, standards, and codes. The study suggests adopting the categorization of modular envelope panels provided in this study and developing modular panels suitable for hot and humid climates to fill the existing knowledge gap.

Hydrodynamic characteristics of rigid net panels for mariculture facilities as determined in flume-tank experiment

Mariculture facilities composed of rigid nets in practical applications gain increasing popularity due to the benefits of high strength and resistance to biofouling. In terms of structural safety and stability, the hydrodynamic characteristics of rigid nets are essential for design optimization and dynamic simulation, yet a comprehensive understanding is currently lacking. Hydrodynamic experiments were thus conducted to investigate four types of rigid net panels in a flume tank. The experiments considered variations in both the angles of attack (ranging from 0° to 90°) and flow velocities (ranging from 0.3 to 1.2 m/s). The results revealed that the drag coefficient of woven net panels exhibited the largest variation range, ranging from 0.13 to 1.26. The tortoise-shell net panels exhibited the lowest drag coefficients when the net panel was normal to the current while the drag coefficients were largest when the net panel was parallel to the current. The maximum lift coefficients, observed when the value of the angle of attack was 50°, were approximately 0.41 for woven net panels, 0.39 for welded net panels, 0.26 for chain-link net panels, and 0.27 for tortoise-shell net panels. Furthermore, hydrodynamic models of rigid net panels with better prediction performances than previous models were proposed. Considering the diverse application scenarios and hydrodynamic differences, utilizing the specific hydrodynamic models to improve prediction accuracy is recommended.

Vibration and damping characteristics of auxetic honeycomb sandwich panels with polyurea-metal laminate face sheets

Vibration and damping characteristics of auxetic honeycomb sandwich panels with polyurea-metal laminate face sheets

On the free vibration characteristics of multiscale hybrid conical panels utilizing Chebyshev–Ritz route

This study investigates the vibrational behavior of three-phase polymer-glass fiber (FG)-carbon nanotubes (CNT) nanocomposites conical panels. Effects of the wavy shape of CNTs and the viscoelastic nature of the polymer matrix are considered. First and foremost, the equivalent material properties are estimated in the context of a three-step hierarchical approach. Then, the governing equations are attained by combining the first-order shear deformation theory (FSDT) and Hamilton’s principle. Furthermore, the Ritz method is employed to extract the frequency responses with the help of Chebyshev polynomials for both simply supported and clamped ends panels. For the parametrical studies, the effect of different geometrical constraints, for instance, the effects of relaxation time and the effect of considering different waviness coefficients for the CNT, are reported. The findings of this paper reveal the significant effect of the viscoelastic properties of the polymer matrix on the estimation of the dimensionless frequency. For instance, under simply supported boundary conditions and a relaxation parameter of 60 s, the frequency of the structure reduces by approximately 23% after 100 s.

A hybrid wave and finite element/boundary element method for predicting the vibroacoustic characteristics of finite-width complex structures

This paper presents a hybrid wave and finite element/boundary element method for predicting the vibroacoustic characteristics of complex panels characterised by an irregular cross-sectional shape with a non-flat upper surface. In this approach, the panels are treated as waveguides and only a small segment of the panel is modelled using finite elements. The mass and stiffness matrices of the segment are then post-processed to project the motion onto its cross-sectional boundaries interfacing with the surrounding fluids. The acoustic pressures in the fluids are modelled by applying Fourier transforms to the Helmholtz boundary integral equations in the wavenumber domain. For each wavenumber component, the pressures acting on the segment are transformed into external nodal forces by evaluating the virtual work performed by the surface pressure on the segment. The wave and finite element formulations are subsequently coupled to the discretised boundary integral equations to determine the response of the panel to acoustic wave excitation. The hybrid method for predicting dispersion curves and sound transmission is validated through comparisons with predictions obtained from both an analytical model and a wave-based method found in the literature. To demonstrate the practical utility of the approach, the hybrid method is employed to predict sound transmission through a corrugated sandwich panel, where developing an analytical model is difficult. The method provides accurate predictions at a low computational cost.

Investigating Vibration Characteristics of Cross-Laminated Timber Panels Made from Fast-Grown Plantation Eucalyptus nitens under Different Support Conditions

The mechanical properties of fibre-managed Eucalyptus nitens (E. nitens) cross-laminated timber (CLT) have previously been extensively studied, proving the material to be structurally safe and reliable. However, the vibration performance of CLT manufactured from this relative new construction species is not yet fully understood, especially under different support conditions. In this study, three types of support conditions, including roller–roller, bearer–bearer and clamp–bearer support conditions, were examined under vibration impulse-response testing performed using a simple but effective and repeatable excitation method consisting of a basketball dropped from a known height and an accelerometer. Six three-ply E. nitens CLT panels considered to have different moduli of elasticity in different layers and one strength-class C24 spruce CLT as a controlled reference were included in this study. The results suggest that the fundamental frequency values can effectively reflect the inherent characteristics of CLT panels (bending stiffness and density); however, no obvious relationship was observed between damping ratios and these inherent properties. The values of frequency constant λ1 were determined to analyse the effect of different support conditions on the values of fundamental frequency. The average values of λ1 for the roller–roller (9.6) and bearer–bearer (10.1) supports align with the theoretical values (9.87) for simply support (S-S) conditions. However, when clamping loads were applied at one edge of the bearer support, the average values of λ1 increased up to 10.8 but remained far below the theoretical values for clamped–pinned (C-S) support (15.4).

The impact‐induced deformation characteristics of polycarbonate panels

AbstractIn this study, the investigation of damage caused by a spherical steel projectile on the polycarbonate (PC) panels has been undertaken both numerically and experimentally. The material properties are obtained from both static and dynamic tests. High‐velocity impact experiments are performed using a pressure‐based projectile launching system. The effect of panel curvatures and impact locations on the deformation are investigated experimentally. The impact locations are selected as both at the plate center and near the edge of the plate. A validation study is performed by analyzing the impact response of a PC plate as previously presented in the literature and subsequently comparing it with the results obtained. An analysis of the impact behavior of PC panels is carried out through numerical simulations using finite element program (LS‐DYNA). The effect of boundary conditions on the impact response is also investigated numerically. Plastic strains, von Mises stresses, dent depth, and energy absorption are obtained. It is indicated by the results that the deformation behavior of PC panels exhibits a strain rate dependence. Additionally, the deformation behavior is influenced by panel curvatures and boundary conditions, emphasizing the necessity to consider these factors in the design of structures, such as canopies made of PC panels.Highlights Provides a comprehensive understanding of polycarbonate behavior. Emphasizes the influence of impact locations and panel curvatures. Dent depth and stress rise with panel curvature, crucial for design considerations. Emphasizes the significance of strain rate and boundary condition in design.

Numerical and experimental study of two common types of fouled net panels in the ocean

In this paper, the hydrodynamic and surrounding flow field characteristics of fouled nets panel are studied based on numerical and experimental methods. The types of fouled nets panel are analyzed and be divided into shell aggregation fouled net and bio-accumulation fouled net according to the attachment location and morphological characteristics of contaminants. Physical models of each type of fouled nets panel are made manually for water tank experiments. The corresponding numerical simplified model was established using the large eddy simulation method for flow field simulation to calculate and analyze the hydrodynamics of the net, capture the subtle changes in the flow field caused by pollutants, quantify and analyze the permeability of each hydroid-fouled nets.

МЕТОД ПІДВИЩЕННЯ ЕНЕРГЕТИЧНОЇ ЕФЕКТИВНОСТІ ФОТОЕЛЕКТРИЧНИХ ПАНЕЛЕЙ ЗА РАХУНОК ПЕРЕТВОРЕННЯ ЇХ У ГІБРИДНИЙ КОЛЕКТОР

Abstract. This work provides a general description of the method of increasing the energy characteristics of solar photovoltaic panels by converting them into a hybrid collector, as well as an economic assessment of the feasibility of using this method and a comparative analysis of efficiency. Due to the increased relevance of autonomous sources of electrical energy in today's society, special attention is paid to renewable energy sources, in particular solar photovoltaic panels. The construction of rooftop SPPs is becoming more and more relevant in the context of modern trends in distributed generation and reliability of electricity supply. Increasing the energy efficiency of solar photovoltaic panels is one of the aspects that harmoniously combines increasing energy sustainability, reliability and autonomy. The essence of the proposed method is to convert any existing solar photovoltaic panel into a hybrid collector through the use of a special device. Due to its design, this device almost does not affect the reduction of the intensity of solar radiation on the surface of the panel, but at the same time it allows receiving heat energy in the form of a heated coolant. Depending on the priority direction of operation of the hybrid collector, it is possible to increase the generation of electrical energy by reducing the surface temperature of the panel, reducing temperature losses, and more fully using thermal energy. Theoretically, it is possible to increase the efficiency of a solar photovoltaic panel by 166% using this method, which is a high indicator. And the specific cost of 1 kW h of energy for this method with full use of thermal energy is 5 times lower compared to existing designs. Key words: electrical energy, photovoltaic solar panels, temperature coefficient, hybrid collector, thermal energy, panel heating, insolation area

Study on photovoltaic characteristics of bifacial solar panels

In the work optimum angles of orientation of solar panels with bifacial silicon solar cell, essentially different from traditional solar panels with simple silicon solar cells are experimentally defined. Are shown optimum distance from a back vertical wall and height from horizon, and also color of a horizontal surface reflecting them for achievement of high efficiency of solar panels with bifacial solar cells. Temperature factors of the main basic photovoltaic parameters of power stations with simple and bifacial silicon solar cells shown. Advantage of use of photovoltaic power stations with bifacial silicon solar cells in the hot climate conditions is revealed.

Uncertainty Quantification of the Crack Propagation Behavior in Welded Stiffened Panels Using a Hybrid Framework Integrating Artificial Neural Networks and Finite Element Analysis

Predicting the crack propagation behavior in welded stiffened panels often used in marine, civil, and aerospace structures, has been challenging. The presence of welded stiffeners creates complex stress conditions that need to be properly considered while predicting the crack growth. Another challenge is the presence of significant uncertainties related to the variability in the geometric parameters. In this context, the proper consideration of the uncertainties associated with these parameters is crucial for the accurate prediction of the fatigue service life and for ensuring structural integrity and operational reliability throughout the service life. This paper conducts a sensitivity analysis to evaluate the effect of relevant input parameters, covering the characteristics of the main panel and stiffener characteristics, on the crack propagation behavior. A 3D finite element analysis, an artificial neural network, and an elastic-plastic crack growth model are integrated to predict crack propagation under cyclic loading. The sensitivity assessment approach is illustrated on stiffened panels with T- and L-shape stiffeners subjected to axial tensile fatigue loading. The proposed approach is validated using experimental test data reported in literature.

Annual Forecast of Photovoltaic Power Generation Based on MLP Artificial Neural Networks

The intermittency of solar energy resources presents a significant challenge in balancing power generation and load demand. To enhance system consistency, forecasting photovoltaic solar energy is crucial. Among numerous techniques, Artificial Neural Network (ANN) is an efficient tool that can help simplify this problem and predict photovoltaic power generation based on various inputs such as weather data and panel characteristics. In this paper, we present the results of an annual forecast of photovoltaic power generation based on Multilayer Perceptrons (MLP), which provides valuable insights into the potential of MLP ANN for accurate and reliable prediction of photovoltaic power generation, thereby improving the efficiency and reliability of photovoltaic systems. The results were obtained based on data collected over a year and validated with data from the following year. Mean Squared Error (MSE) was utilized to quantify the error between the predicted and measured photovoltaic solar energy generation. The analysis demonstrated that this annual forecast of photovoltaic power generation is highly accurate.

Structural and Mechanical Characteristics of Sustainable Concrete Composite Panels Reinforced with Pre-Treated Recycled Tire Rubber

Structural and Mechanical Characteristics of Sustainable Concrete Composite Panels Reinforced with Pre-Treated Recycled Tire Rubber

A Method for Extracting Photovoltaic Panels from High-Resolution Optical Remote Sensing Images Guided by Prior Knowledge

The extraction of photovoltaic (PV) panels from remote sensing images is of great significance for estimating the power generation of solar photovoltaic systems and informing government decisions. The implementation of existing methods often struggles with complex background interference and confusion between the background and the PV panels. As a result, the completeness and edge clarity of PV panel extraction results are compromised. Moreover, most previous studies have overlooked the unique color characteristics of PV panels. To alleviate these deficiencies and limitations, a method for extracting photovoltaic panels from high-resolution optical remote sensing images guided by prior knowledge (PKGPVN) is proposed. Firstly, aiming to address the problems related to missed extractions and background misjudgments, a Photovoltaic Index (PVI) based on visible images in the three-band is constructed to serve as prior knowledge to differentiate between PV panels and non-PV panels. Secondly, in order to strengthen information interaction between shallow features and deep features and enhance the accuracy and integrity of results, a Residual Convolution Hybrid Attention Module (RCHAM) is introduced into the skip-connection of the encoding–decoding structure. Finally, for the purpose of reducing the phenomenon of blurred edges, a multilevel Feature Loss (FL) function is designed to monitor the prediction results at different scales. Comparative experiments are conducted with seven methods, including U-Net, on publicly available datasets. The experimental results show that our PKGPVN achieves superior performance in terms of evaluation metrics such as IoU (above 82%), Precision (above 91%), Recall (above 89%), and F1-score (above 90%) on the AIR-PV dataset. Additionally, the ablation experiments illustrate the effectiveness of our key parts. The proposed method reduces the phenomena of missed extractions and background misjudgments effectively while producing highly accurate results with clear boundaries.

Development low-cost processor for photovoltaic simulator

The power generated by a PV array is affected by several factors such as the intensity of solar radiation, the temperature, and the shade cast by solar radiation on the solar panels’ surface. In order to provide the maximum electrical power, it is important to understand the characteristics of a PV system. In this paper, a simulator to observe the characteristics of solar panels is modeled and designed by utilizing tungsten-halogen lamps as a lighting source. The use of halogen lamps ensures that the solar panels’ output signal does not have a large ripple. It differs from other lamps, such as LEDs, which can generate greater ripples in solar panel output signals. Voltage sensors and current sensors are used to obtain the desired values of voltage and current parameters. The characteristics of solar panels with different combinations of lighting can be observed using a Personal Computer (PC) both in the form of tables and graphics with the help of the Parallax Data Acquisition tool (PLX-DAQ). According to the results of the test, the simulator can operate properly, and the measured parameter value can be monitored in realtime in the form of current and voltage graphs.

Effect of Small Concaves Surface on the Acoustical Characteristics of Chicken Feather Panel

This study aims to determine the impact of small concave surfaces on the acoustic characteristics of chicken feather panels. Based on the feather-glue ratio reference, the researchers applied a mixture of 70% feather and 30% PVAc for the production of the specimens. In the first stage, the absorption coefficient of the specimen on a small concave surface (CS) was measured using an impedance tube type B&K 4602 with two microphones and a set of computer FFT analyzers. The measurement results were then compared with the absorption coefficient of similar test objects with flat surfaces (FS). The acoustic characteristics of the two types of surfaces (FS and CS) in the specimen panel showed the maximum absorption coefficient (α) value of 0.52 and 0.63 for FS and CS, respectively. These results indicate that specimens with a small concave surface (CS) have a relatively higher absorption coefficient than those with a flat surface (FS). However, further studies are needed to identify other characteristics of these acoustic panels, including their resistance to environmental influences.