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VARIABLE TIME TRIBOLOGICAL BEHAVIOR OF A DEPOSIT METAL E316L-17
Wear and corrosion are the main problems of mechanical elements in mechanical contact, and this results in enormous economic losses. This work describes the tribological effects during the variation of the friction time (1h, 3h, 12h and 24h) and the electrochemical behavior of the substrate solder coating. E316L-17/25CD4 using electric arc welding process. The tribological tests studied such as resistance to wear and coefficient of friction were carried out by a ball test with a friction speed of 20mm/s. The polarization curves were used to evaluate the electrochemical behavior (corrosion resistance) of the upper part of the hard coating. It was found that the wear resistance of E316L-17 increased with hardness. The corrosion current density of the coatings was determined. Voir les détails
Mots clés : E 316L-17, 25CD4 steel substrate, Electrochemical behavior, Tribological properties
Multiyear Load Growth Based TechnoFinancial Li-ion Discharge and Corrosion Behaviors in a Microgrid Located in Algeria
The primary current-collector materials used in lithium-ion cells, aluminum and copper, are both susceptible to environmental degradation. Localized corrosion occurred on bare aluminum electrodes during simulated ambient-temperature cycling in an excess of electrolyte. The highly oxidizing potential associated with the positive electrode charge condition was the most important factor. In contrast to typical aqueous electrolyte pitting, each site was filled with a mixed metal/metal-oxide product, forming surface mounds or nodules. The status quo for relaying such confidence is economic and technical planning models, which are used to design microgrids and distributed energy resources DER. Long-term DER investments and short-term DER dispatch are typically determined by these models. This paper investigates the optimal cost analysis of a hybrid (photovoltaic-diesel) renewable energy system (HRES) in the Adrar region based on the Total Net Present Cost (TNPC). The Hybrid Optimization Model for Electric Renewable is used to perform the optimal cost analysis of HRES. Furthermore, the system is simulated for each time step for each year of the project's 20-year lifespan. The trade-off for this model, which captures battery storage levels from year to year, photovoltaic performance degradation, and diesel cost escalation above the inflation rate, is that the model is more precise, but the calculation takes longer. To begin, we ran the model without Multi-Year and used the Optimizer to find the best system design. The optimal system for the single-year model includes a Danvest generator with 760 kW, 200 kWh of recommended Li-ion storage, and a slightly lower COE of $0.309/kWh. Various scenarios have been simulated, taking into account variations in the power production of the gasified biomass generator, and various solutions to ensure the balance generation/consumption have been analyzed. Voir les détails
Mots clés : corrosion, Diesel, Financial planning optimization, Hybrid energy system (HES), Li-ion battery, Multi-year planning, Microgrid, Photovoltaic, Technical planning optimization, total net present cost
Prediction of Lifetime System Electric Performances Based on Battery Corrosion Effects Included in a Stand Alone Hybrid System- a Case Stud
The ideal system type of this paper work demonstrates that wind power does make sense in situations with high wind speeds and high gasoline prices. The suggested hybrid power system prevented 16.26 t/y of CO2 gas from being added to the village's local environment and saved 6176.15 liters of fossil fuel per year. Aluminum is prone to pitting corrosion and copper to environmentally aided cracking, which are the two main current-collector materials used in lithium-ion batteries. In the other hand. The corrosion process that happens at the interface between the active material and grid material of the positive plate of the lead-acid battery storage is discussed in this paper's technical performance implications. The system is modelled for each time step for each year of the project's 20-year lifespan. In order to discover the ideal system architecture, we first ran the model without Multi-Year and utilized the Optimizer. This study's objective is to carry out technical and financial optimization throughout the energy system's lifespan while taking into consideration the mixed storage system's corrosion-related deterioration as a key parameter. The best cost study for the HRES is completed with the assistance of the HOMER Pro MATLAB Link. Voir les détails
Mots clés : Battery, corrosion, Multi-year planning, planning optimization
Multiyear Load Growth Based Techno-Financial Li-ion Discharge and Corrosion Behaviors in a Microgrid Located in Algeria
The primary current-collector materials used in lithium-ion cells, aluminum and copper, are both susceptible to environmental degradation. Localized corrosion occurred on bare aluminum electrodes during simulated ambient-temperature cycling in an excess of electrolyte. The highly oxidizing potential associated with the positive electrode charge condition was the most important factor. In contrast to typical aqueous electrolyte pitting, each site was filled with a mixed metal/metal-oxide product, forming surface mounds or nodules. The status quo for relaying such confidence is economic and technical planning models, which are used to design microgrids and distributed energy resources DER. Long-term DER investments and short-term DER dispatch are typically determined by these models. This paper investigates the optimal cost analysis of a hybrid (photovoltaic-diesel) renewable energy system (HRES) in the Adrar region based on the Total Net Present Cost (TNPC). The Hybrid Optimization Model for Electric Renewable is used to perform the optimal cost analysis of HRES. Furthermore, the system is simulated for each time step for each year of the project's 20-year lifespan. The trade-off for this model, which captures battery storage levels from year to year, photovoltaic performance degradation, and diesel cost escalation above the inflation rate, is that the model is more precise, but the calculation takes longer. To begin, we ran the model without MultiYear and used the Optimizer to find the best system design. The optimal system for the single-year model includes a Danvest generator with 760 kW, 200 kWh of recommended Li-ion storage, and a slightly lower COE of $0.309/kWh. Various scenarios have been simulated, taking into account variations in the power production of the gasified biomass generator, and various solutions to ensure the balance generation/consumption have been analyzed. Voir les détails
Mots clés : corrosion, Diesel, Financial planning optimization, Hybrid energy system (HES), Li-ion battery, Multi-year planning, Microgrid, Photovoltaic, Technical planning optimization, total net present cost
Economic Evaluation of Degradation by Corrosion of an On-Grid Battery Energy Storage System: A Case Study in Algeria Territory
Economic planning models, which are used to build microgrids and Distributed Energy Resources (DER), are the current norm for expressing such confidence. These models often decide both short-term DER dispatch and long-term DER investments. This research investigates the most cost-effective hybrid (photovoltaicdiesel) renewable energy system (HRES) based on Total Net Present Cost (TNPC) in an Algerian Saharan area, which has a high potential for solar irradiation and has a production capacity of 1 GW/h. Leadacid batteries have been around much longer and are easier to understand, but have limited storage capacity. Lithium-ion batteries last longer, are lighter, but generally more expensive. By combining the advantages of each chemistry, we produce cost-effective highcapacity battery banks that operate solely on AC coupling. The financial implications of this research describe the corrosion process that occurs at the interface between the active material and grid material of the positive plate of a lead-acid battery. The best cost study for the HRES is completed with the assistance of the HOMER Pro MATLAB Link. Additionally, during the course of the project's 20 years, the system is simulated for each time step. In this model, which takes into consideration decline in solar efficiency, changes in battery storage levels over time, and rises in fuel prices above the rate of inflation, the trade-off is that the model is more accurate, but the computation takes longer. We initially utilized the optimizer to run the model without multi-year in order to discover the best system architecture. The optimal system for the single-year scenario is the Danvest generator, which has 760 kW, 200 kWh of the necessary quantity of lead-acid storage, and a somewhat lower Cost Of Energy (COE) of $0.309/kWh. Different scenarios that account for fluctuations in the gasified biomass generator's production of electricity have been simulated, and various strategies to guarantee the balance between generation and consumption have been investigated. Voir les détails
Mots clés : Battery, corrosion, Diesel, Economic planning optimization, Hybrid energy system, HES, Lead-acid battery, Li-ion battery, Multi-year planning, Microgrid, price forecast, total net present cost, Wind
Fusion and heat affected zones damage during fatigue assessment assisted by digital image correlation
This work aims at following strain field expansion incurred in welded austenitic stainless steel during cyclic loading assisted by three dimensional Digital Image Correlation (3D DIC) method. The latter is an indicative device helping to distinguish the high stressed area from the low stressed one during fatigue test. 3D DIC monitoring of strain field and stress condensation in the studied area reveals the presence of simultaneous strain localization in two regions bordering between them an area with a reduced stress level. SEM-ECCI analysis of the hybrid zone supposes that the microstructural damage in the welded joint would be controlled by hardening and softening phenomena, caused by sub-grains formation and twins annihilation during loading Voir les détails
Mots clés : Cracks, Image processing, Strain mapping, Welded joint
Damage Analysis In Open Hole Composite Specimens By Acoustic Emission: Experimental Investigation
In the present work, an experimental study is carried out using acoustic emission and DIC techniques to analyze the damage of open hole woven composite carbon/epoxy under solicitations. Damage mechanisms were identified based on acoustic emission parameters such as amplitude, energy, and cumulative account and rise time. The findings of the AE measurement were successfully identified by digital image correlation (DIC) measurements. The evolution value of bolt angle inclination during tensile tests was studied and analyzed. Consequently, the relationship between the bolts inclinations angles during tensile tests associated with failure modes of composite materials fastened joints is determined. Moreover, there is an interaction between laminate pattern, laminate thickness, fastener size and type, surface strain concentrations, and out-of-plane displacement. Conclusions are supported by microscopic visualizations of the composite specimen. Voir les détails
Mots clés : damage analysis, composite specimens, acoustic emission
Characterization of an ultrasound reception chain based of a PVDF membrane hydrophone
Ultrasound is commonly used in different applications such as the defects detection in materials, underwater detection, medical and biological applications. In all this applications, it is necessary to have a system allowing the emission of ultrasonic waves and their reception. In general, this system is essentially composed of an electric generator, a transmitter transducer, a receiver transducer and a display or recording system. The purpose of this work is the functioning characterization of a measurement chain comprising a receiver transducer with PVDF membrane connected by means of a coaxial cable to an oscilloscope. This theoretical model proposed, allows the determination of the impulse response in the temporal domain or the transfer function in the frequency domain of the entire reception measurement chain. In this study, special attention is given to the receiving transducer as the main element of the receiving chain. Voir les détails
Mots clés : PVDF membrane, ultrasound reception chain, transfer function, impulse response, transfer Matrix
Modeling Cracks Using Digital Images Correlation and Phase-Field FE Analysis Techniques
In this work, the recently developed phase field fracture along with digital images correlation DIC techniques are used to study mode I crack behavior, an elastic brittle phase field model which is well implemented in some finite elements codes is used, in this model the damage evolution is driven only by elastic strains and is governed by the classical brittle phase-field law, the opensource digital images correlation Ncorr code is used to extract full displacement and strain field from experiments, this open-source DIC code can treats cracks in structure by taking into account discontinuities through the sub-sets, the discontinuities in the displacement field are well captured and used in the out-puts to compute the size of crack by tracking and locating the position of the crack tip, the best results are obtained by finding the smallest DIC parameters (sub-sets size and radius) which gives results without noise. Results are expressed in term of plots of displacement vs reaction-force, contour plots of displacement and strain field components, crack tip opening displacement and fracture path tracking. Results from both approaches are presented and then a discussed is conducted to show the capabilities of both methods to study and track crack evolution in structures under mode I loading. Voir les détails
Mots clés : Cracks, Finite Element Analysis, Phase Field Fracture, Digital Images Correlation, Ncorr
Finite element investigation of the elasto-plastic behavior of AA6005 using the Hansel-Spittel rheological model and the Cockcroft and Latham fracture model
Understanding the behavior of materials requires accurate and expensive mechanical tests at different temperatures and stresses. The current trend toward numerical simulation has become an essential engineering tool. Therefore, researchers have made efforts in this area by building mathematical models based on experimental data. These models include data regarding the actual physical behavior of the material, such as its temperature sensitivity, strain rate sensitivity, and strain sensitivity. The constitutive equations of Hensel and Spittel (H-S) [1] have been frequently used (FES), due to their ease of numerical implementation, the inclusion of stress and strain history, and the calibration of parameters from tests. The objective of this work is to determine the mechanical characteristics of the aluminum alloy (AA 6005), taking into account the effect of work hardening. This behavior is then tested using finite element analysis tools to model it. The experimental results showed that the work-hardening behavior of the alloy (AA 6005) at room temperature is similar to all quasi-static strain rates studied in this work. In addition, in the range of strain rates investigated in this study, the finite element results correlate well with the experimental results. The simulated results can be really reliable only when a good constitutive equation is employed. Voir les détails
Mots clés : tensile test, rheological behavior Hasel-Spittel, Ductile Damage Fracture criterion