Hasil untuk "Mechanical industries"

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DOAJ Open Access 2026
Foundation of self-powered carbon-neutral renewable polygeneration: Integrations into biomass gasification

Manish Meena, Nitin Dutt Chaturvedi

Biomass gasification converts solid biomass into a combustible syngas, enabling cleaner heat and energy than direct combustion. This suffers from efficiency and economic drawbacks due to inherent energy losses when deployed as a standalone technology. Centralised dependency for energy requirements has a major influence on annual operations and may disrupt over time. This study presents a novel self-powered polygeneration system that reduces carbon emissions by integrating processes to concurrently produce distinct products, overcoming the conventional drawbacks. The process was simulated in Aspen Plus, following the sensitivity analysis, heat integration, and economic analysis. The MATLAB simulation is conducted to analyse the integrated energy supply. This integrates biomass gasification to produce Methane, Biochar, Methanol, Dimethyl ether, Hydrogen, Power, and Heat. This maximises resource efficiency and economic effectiveness by diversifying product and revenue streams. This includes numerous integrations driven by distinct decision variables, which make experimental analysis challenging. Future research must be conducted to identify robust designs and operational sustainability.

Energy industries. Energy policy. Fuel trade, Renewable energy sources
DOAJ Open Access 2026
Optimizing electric vehicle fleets to develop smart charging infrastructure: a digital twin approach

Anubhav Kumar Pandey, Amitha B., Nandini K. Krishnamurthy

Abstract The accelerated shift to green transportation demands new ideas to perform effective management of charging systems for electric vehicles (EVs). This paper explores the approaches of digital twins (DTs) to manage smart charging powered by renewable energy along with grid supply integration to EV fleets. DTs create a virtual environment that enables energy flow, charging times, and grid connections by modelling various parameters of charging stations. The DT also supports forecasting techniques, enhanced usage of renewable energy, and battery storage handling to improve performance and reduce operational costs to promote environmental friendliness. The work also gives important insights into the necessity of DTs in smart charging, related operational constraints, and the relevance of DTs in community-based sustainable development. This paper similarly emphasizes the crucial role of DTs in improving the management and control of EV fleets, resulting in greater independence and shorter payback periods while establishing the foundation for future and scalable applications. DTs offer ample opportunities in this domain, and this research aims to open new avenues to enable future developments that aim to expand the DTs’ functionality for wider energy applications by refining optimization tools with greater energy efficiency. This work comprehensively highlights the potential of DTs and their crucial role in promoting future transportation along with a few limitations like data latency and cybersecurity-related issues to enable seamless integration of EVs with the virtual counterparts.

Renewable energy sources, Energy industries. Energy policy. Fuel trade
DOAJ Open Access 2025
Scalability analysis of heavy-duty gas turbines using data-driven machine learning

Shubhasmita Pati, Julian D. Osorio, Mayank Panwar et al.

With the increasing integration of variable renewable energy sources into power systems, the role of flexible power generation technologies like gas turbines (GT) in rapid grid balancing remains crucial. This sustained importance underscores the need for scaled and precise modeling of GT to ensure effective integration within evolving energy frameworks. While physics-driven GT models integrate thermodynamics, fluid dynamics, and combustion principles, they often rely on approximate mathematical representations to accommodate scaling that may not capture the actual complex dynamics for GTs and inertial effects associated to GTs with different ratings. In this study, a data-driven model is proposed using machine learning (ML) techniques to conduct GT scalability analysis and performance evaluation with high accuracy. The ML model, trained on data from various operating conditions and performance parameters, aims to uncover intricate relationships and patterns, resembling GT characteristics at different scales (ratings). The model is developed to capture complex system interaction and to adapt to changing operational scenarios at different capacities, providing valuable insights of power system dynamics. In this study, the real-time digital simulator platform was employed to generate training data for the ML model and assess its dynamic characteristics. The ultimate objective was to develop a detailed modeling framework based on governing equations and data-driven ML capable of predicting key performance indicators, in thermal systems such as GTs, including power output, speed, fuel consumption, and exhaust temperature under diverse operating conditions at different scales. The developed ML framework demonstrated high accuracy, with mean relative errors for GT power prediction, reference speed, exhaust temperature, and compressor pressure ratio (CPR) parameters consistently below 0.1% across typical load fluctuation scenarios. Maximum deviations were limited to approximately 0.5K for exhaust temperature and 0.009 for CPR, underscoring the model’s ability to replicating dynamic GT behavior with high precision. The adaptability of the ML model enables its application across diverse operational conditions and its extension to other thermal systems. By leveraging advanced ML techniques, this study presents a robust and scalable modeling framework that enhances GT simulation precision, facilitating improved integration into evolving power systems.

Energy industries. Energy policy. Fuel trade, Renewable energy sources
DOAJ Open Access 2024
Impacts of T6 heat treatment on the microstructural, mechanical, and corrosion properties of thixoformed AA7075 alloy produced by cooling slope casting

Serhat Acar, Kerem Altug Guler

Research into semi-solid metal forming techniques has been ongoing for an extended period with the aim of producing near-net shape products from aluminum alloys. The primary focus has traditionally been on casting alloys seeking to offer an alternative to the other processes such as high pressure die casting. Over the past twenty years, wrought aluminum alloys have also been explored for thixoforming operations as an alternative to traditional plastic deformation techniques. This research investigated the impacts of T6 heat treatment on the microstructural, mechanical, and corrosion properties of AA7075 alloy samples produced through cooling slope casting and subsequent thixoforming with different reheating durations. The selected alloy was chosen due to its widespread use in various industries, attributed to its excellent strength-to-density ratio achieved after T6 heat treatment. Building on optimized cooling slope casting parameters from a prior study, the standard solution treatment procedure following thixoforming with extended reheating times was found to be inadequate. Hardness and tensile tests revealed that specimens reheated for 120 min exhibited significantly reduced response to T6 treatment. Despite achieving the targeted hardness value of 154 HB with samples reheated for 20 min prior to thixoforming and T6 heat treatment, especially the elongation at break values were unsatisfactory. Potentiodynamic polarization tests indicated that corrosion primarily involved grain dissolution, with longer reheating times decreasing corrosion resistance due to increased amount of secondary phases and grain isolation. These findings highlight that while AA7075 alloy can be processed into semi-solid formable materials via cooling slope casting, issues such as hot tearing, micro-shrinkage, and physical defects post-thixoforming hinder the achievement of desired tensile properties.

Materials of engineering and construction. Mechanics of materials, Chemical technology
DOAJ Open Access 2024
Applications of micro-nanobubble and its influence on concrete properties: An in-depth review

Tushmanlo Abolfazl Soleymani, Tushmanlo Hamid Soleymani, Asadollahfardi Gholamreza et al.

Micro-nanobubbles (MNBs) are tiny bubbles of water used in various industries. The production methods and properties of concrete containing MNBs and the applications of MNBs in different industries are reviewed. Then, the effect of MNBs on the properties of fresh and hardened concrete is described. Next, we assessed the advantages and disadvantages of using MNBs in different types of concretes, environmental and economic impact, and research gaps in the concrete containing MNBs. Even though the presence of MNBs in concrete has an undesirable effect on workability and rheology parameters, the results of workability are in the range of the European Guideline for Self-compacting Concrete regulations and the British Standard for conventional concrete. In contrast, using sulfo-aluminate cement instead of Portland cement and MNBs in concrete improves rheological characteristics. The review also shows that MNBs improve the mechanical properties of concrete by up to 31% for compressive strength, 10–20% for tensile, and 3–34% for flexural strength. Furthermore, concrete containing MNBs has performed better than conventional concrete in terms of durability properties such as electrical resistivity, ultrasonic pulse velocity, chloride penetration resistance, and resistance to freezing–thawing cycles (F-T cycle). MNBs in concrete reduce the porosity by 17% and decrease the size of the holes. Water absorption of MNB concrete at 28 days decreased by 20%, and chloride permeability reduced by 20%. MNBs in concrete help to develop the resistance of cement-based materials improve the elastic modulus at early ages and increase the ability to resist cracking, which can reduce the crack width. Still, it is necessary to carry out more experimental work for workability and durability, especially for SCC. Even though a few studies indicate a slight impact on the environment, environmental and economic effects, and production challenges need more investigations.

Technology, Chemical technology
DOAJ Open Access 2024
Heat recovery analysis of a fixed plate energy recovery ventilator

Adams Moro, Patricia Kwakye-Boateng

Abstract As building becomes more leak-tight, air refreshment to improve indoor air quality is needed for healthy living standards. In the quest to ensure comfortable indoor climatic conditions, energy recovery ventilators (ERV) are used to provide air refreshment and thermal comfort. In this study, a fixed plate air-to-air ERV was analysed to determine its effectivity in terms of energy recovery during air refreshment. A customized test bench was built and used to acquire the instantaneous surface temperatures of the heat exchanger plates contained in the ERV during air refreshment. Also, a numerical model of the ERV was developed and validated by comparing its output from simulation with experiment results under the same conditions. The model consisted of a single heat exchanger plate and the air across the plate surface. To capture the effect of heat transfer between the air and the heat exchanger plate in 3D, the model was discretized into numerous cells. From the experiment and simulation results, the air-to-air ERVs were more effective in recovering thermal energy at low flow velocity than at high flow velocity. At lower flow velocity, it will take a longer time duration before any significant impact is made on the thermal conditions of the building, comparatively. The prediction of the model was within acceptable margins and could be used to provide insight on the ERVs performance improvement.

Renewable energy sources, Energy industries. Energy policy. Fuel trade
DOAJ Open Access 2024
A perspective on mechanoluminescence and multipiezo in ferroelectric materials

Tomoki Uchiyama, Xu-Guang Zheng, Chao-Nan Xu

The discovery of innovative mechanoluminescence materials of SrAl2O4 and ZnS, which emit repeatable light [repeatable mechanoluminescence (ML), hereafter simply ML] even by soft touch, has trigged intense research interest in material/device/system development for applications across various fields. This perspective presents an overview of the crystal structures, mechanisms, and ML behaviors of most promising systems, namely, SrAl2O4-, ZnS-, LiNbO3-, and Sr3Sn2O7-based ferroelectric materials. These multipiezo materials, which simultaneously exhibit intrinsic piezoluminescence (true elastic deformation induced ML and no friction effect) and piezoelectricity, show distinct and valuable characteristics by integrating mechanical force, electric field, and light for stress sensing and other applications. Recent studies indicated the critical role of crystal structure, doping, and piezoelectric properties in achieving robust and reliable ML performance. These findings suggest that ML materials hold substantial promise for applications in stress/force sensing, structural health monitoring, mechanically activated lighting, and advanced imaging techniques. Further investigation and advancement of multipiezo materials could yield breakthroughs, further augmenting their usefulness across various industries and scientific domains. Exploring ferroelectric ML materials offer new prospects for developing advanced materials with unique electro-mechano-optical properties.

Biotechnology, Physics
DOAJ Open Access 2024
Experimental analysis of low-velocity impact behaviour on flax-balsa biobased sandwich

Zouhaier Jendli, Mondher Haggui, Arthur Monti et al.

This article deals with a detailed experimental study dedicated to the evaluation of the overall mechanical behaviour of a bio-based composite structure used in transportation industries. The sandwich structure is designed to increase the lightening, vibration damping, and composite recyclability. The considered materials consist of a Flax/Elium® laminate composite for skins associated with a balsa core. The sandwich structure was obtained using a one-shot liquid resin infusion process. Low-velocity impact tests were carried out on different sandwich configurations with the aim of characterizing the effects of the stacking sequence and the density and thickness of the core. Furthermore, an experimental comparative analysis was conducted involving two composite laminate types: Glass/Elium and Flax/Elium to enhance the specific behaviour of flax fibre composite to be used as skins in the sandwich structures. The impact tests were carried out at low velocities and at different levels of impact energy using a drop-weight test bench. Notable damage mechanisms have been identified, and a chronological sequence of their development has been suggested. Ultrasonic analyses using C-Scan imaging were applied to the opposite side of the impacted specimen. The research proves the efficient energy-absorbing capability of the biobased sandwich structure during impact. Finally, this study enables a deeper understanding of various parameters that influence the behaviour of sandwiches during low-velocity impacts, thereby facilitating more informed material selection for practical applications.

Materials of engineering and construction. Mechanics of materials
DOAJ Open Access 2024
Development and construction of a mechanized moving platform for human service

Volodymyr Rashkivskyi, Mykola Prystailo, Bohdan Fedyshyn et al.

The purpose of the proposed article is the development and construction of a mechanized mobile platform for serving people, which is caused by the need to increase the safety of the operation of such technical means, in particular, in the case of the need for mass customer service. The methodology is based on search, research and creative approaches. The methods of development analysis, patent search, synthesis of technical solutions, simulation modelling was used. Scientific novelty. The study of the features of various approaches to the creation of effective mechanized moving platforms, the analysis of solutions and the dynamics of patenting made it possible to substantiate the directions of development of technical solutions and the prospects of developments. The authors proposed constructive solutions for mobile platforms, developed approaches to the technical implementation of increasing the safety of their operation, proposed energy-saving approaches aimed at reducing the energy consumption of mechanized means, which is especially relevant in the mass implementation of platforms for serving people. Research results. The article solves important safety issues of human service, in particular in the entertainment industry through the development of structural parts, drives and rules for the operation of mechanized moving platforms. Synthesized constructive solutions obtained in the course of patent research, analysis of modern technical solutions, rational technical design, and expert evaluation are presented. It was determined that the safety of the operation of mechanized moving platforms, which are intended for the transport of people in the field of tourism, depends on effective approaches to the design and components of the technical system in the form of a moving platform, its structural components, elements of its mechanism and the drive system as a whole, which with the optimization of technical indicators the stability of the overall system, the smoothness of movement and braking of the platform, the optimization of the materiality of the structure in total allow to have a qualitative effect on improving the safety of human operation.

Technological innovations. Automation, Mechanical industries
DOAJ Open Access 2023
Tailoring the microstructure and mechanical properties of Cu–Fe alloy by varying the rolling path and rolling temperature

Jing Xu, Bo Guan, Rui Fu et al.

Cu–Fe alloys are expected to be extensively used in electronics, transportation and machinery industries due to the extraordinary mechanical properties and functional properties. To optimize rolling process and the final properties of Cu–Fe plates. The effect of rolling path, rolling temperature and thickness reduction on microstructure evolution, mechanical and electrical properties of Cu–Fe alloy are carefully investigated. The results shown that the thickness reduction has a significant effect on mechanical properties of Cu–Fe alloy. The yield strength of Cu–Fe plates with 20% thickness reduction is more than 2 times higher than that of homogenized ingot. While the yield strength increases gradually as further increasing the thickness reduction. Rolling temperature is an important parameter determining the strength-ductility balance. The strength of plate rolled with 80% thickness reduction at 400 °C is similar to that of the plates in cold-rolled state, and the ductility is higher than that for the plates in the cold-rolled state. Further investigation reveals that the formation of heterogeneous structure characterized with recrystallized-fine grains embedded in deformed-coarse grains is responsible for the observed extraordinary mechanical properties. Rolling path could also affect the microstructure evolution and formability of the plates. For plate rolled with route 1 (unidirectional rolling), a stronger Copper-type texture with two Brass-type textures are observed. For plate rolled with route 2, where the rolled plate is rotated to 90° with respect to previous rolling direction between adjacent rolling passes, only Brass-type texture is generated. A rolling-path dependent edge-crack behavior is observed during rolling. Edge cracks are generated during rolling with route 2, while the edge cracks are not observed for plates rolled with route 1. Factors affecting the edge-cracks behavior are also discussed.

Mining engineering. Metallurgy
DOAJ Open Access 2022
Probing into the properties of B4C reinforced nickel phosphorus-based nanocomposite coating

Osama Fayyaz, Moinuddin M. Yusuf, Sara Bagherifard et al.

Nickel-based coatings are well known for their good corrosion resistance performance. However, these materials suffer from inferior mechanical properties that limit their wider application. This work investigates the synthesis, and performs an exhaustive characterization, of Ni–P–B4C nanocomposite coatings developed through conventional electrodeposition using a modified Watts bath. The study examines the effect of an increase in the concentration of boron carbide nanoparticles (BCNPs) on the structural, morphological, topographical, mechanical and electrochemical properties of the nanocomposite coating. Vickers microhardness tester and nanoindentation technique were utilized to elucidate the role of BCNPs in modifying the mechanical response of nanocomposite coatings. Furthermore, corrosion resistance of the nanocomposite coatings was investigated through d.c potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Comparison of the properties of the developed coatings revealed the remarkable improvement in the properties of Ni–P–B4C nanocomposite coatings when compared to the bare mild steel substrate and the Ni–P coatings. The enhanced corrosion resistance and superior mechanical properties of Ni–P–B4C nanocomposite coatings make them attractive for many industries. Based upon the experimental findings, a possible mechanism for the synthesis and improved corrosion resistance of Ni–P–B4C nanocomposite coatings was also proposed.

Mining engineering. Metallurgy

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