Search results for: recovery stress
608 Study on Rupture of Tube Type Crash Energy Absorber using Finite Element Method
Authors: Won Mok. Choi, Tae Su. Kwon, Hyun Sung. Jung, Jin Sung. Kim
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The aim of this paper is to confirm the effect of key design parameters, the punch radius and punch angle, on rupture of the expansion tube using a finite element analysis with a ductile damage model. The results of the finite element analysis indicated that the expansion ratio of the tube was mainly affected by the radius of the punch. However, the rupture was more affected by the punch angle than the radius of the punch. The existence of a specific punch angle, at which rupture did not occur, even if the radius of the punch was increased, was found.Keywords: Expansion tube, Ductile damage, Shear failure, Stress triaxiality.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1724607 Approximate Tension Buckling Capacity of Thin Edge-Cracked Web Plate Subjected to Pure Bending
Authors: Sebastian B. Mendes
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The presence of a vertical edge-crack within a web plate subjected to pure bending induces local compressive stresses about the crack which may cause tension buckling. Approximate theoretical expressions were derived for the critical far-field tensile stress and bending moment capacity of an edge-cracked web plate associated with tension buckling. These expressions were validated with finite element analyses and used to investigate the possibility of tension buckling in web-cracked trial girders. It was found that tension buckling is an unlikely occurrence unless the web is relatively thin or the crack is very long.Keywords: Fatigue crack, tension buckling, Rayleigh-Ritz, structural stability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2013606 Preparation and Characterization of Recycled PET/PP Blends from Automotive Textile Waste for Use in the Furniture Edge Banding Sector
Authors: Merve Ozer, Tolga Gokkurt, Yasemen Gokkurt, Ezgi Bozbey
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In this study, research has been conducted on the recovery of automotive textile waste, which has heavy use in the automotive sector and consists of PET/PP content, through the upcycling technique of post-product and post-consumer usage. The aim is to investigate the formulation and production methods that will enable the substitution of original PP raw materials, used in the production of plastic edge bands, with PP/PET alloys. The lamination structure of the mentioned waste makes it impossible to separate the incompatible PP and PET phases, thereby hindering the production of high-quality raw materials or products through recycling. In this study, a comprehensive process was examined through a two-step production process using different types of block and maleic-grafted copolymers to achieve compatibility between these two incompatible phases. The obtained plastic raw materials, referred to as PP/PET blends, were examined in detail, with a focus on their mechanical, thermal, and morphological properties, to discuss their substitutability for the original raw materials.
Keywords: Twin screw extruders, mechanical recycling, melt blending, plastic blends, polyethylene, polypropylene, recycling of plastics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 176605 Novel Security Strategy for Real Time Digital Videos
Authors: Prakash Devale, R. S. Prasad, Amol Dhumane, Pritesh Patil
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Now a days video data embedding approach is a very challenging and interesting task towards keeping real time video data secure. We can implement and use this technique with high-level applications. As the rate-distortion of any image is not confirmed, because the gain provided by accurate image frame segmentation are balanced by the inefficiency of coding objects of arbitrary shape, with a lot factors like losses that depend on both the coding scheme and the object structure. By using rate controller in association with the encoder one can dynamically adjust the target bitrate. This paper discusses about to keep secure videos by mixing signature data with negligible distortion in the original video, and to keep steganographic video as closely as possible to the quality of the original video. In this discussion we propose the method for embedding the signature data into separate video frames by the use of block Discrete Cosine Transform. These frames are then encoded by real time encoding H.264 scheme concepts. After processing, at receiver end recovery of original video and the signature data is proposed.
Keywords: Data Hiding, Digital Watermarking, video coding H.264, Rate Control, Block DCT.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1561604 Alteration of Bone Strength in Osteoporosis of Mouse Femora: Computational Study Based on Micro CT Images
Authors: Changsoo Chon, Sangkuy Han, Donghyun Seo, Jihyung Park, Bokku Kang, Hansung Kim, Keyoungjin Chun, Cheolwoong Ko
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The purpose of the study is to develop a finite element model based on 3D bone structural images of Micro-CT and to analyze the stress distribution for the osteoporosis mouse femora. In this study, results of finite element analysis show that the early osteoporosis of mouse model decreased a bone density in trabecular region; however, the bone density in cortical region increased.
Keywords: Micro-CT, finite element analysis, osteoporosis, bone strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1701603 Mechanical Equation of State in an Al-Li Alloy
Authors: Jung-Ho Moon, Tae Kwon Ha
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Existence of plastic equation of state has been investigated by performing a series of load relaxation tests at various temperatures using an Al-Li alloy. A plastic equation of state is first developed from a simple kinetics consideration for a mechanical activation process of a leading dislocation piled up against grain boundaries. A series of load relaxation test has been conducted at temperatures ranging from 200 to 530oC to obtain the stress-strain rate curves. A plastic equation of state has been derived from a simple consideration of dislocation kinetics and confirmed by experimental results.
Keywords: Plastic equation of state, Dislocation kinetics, Load relaxation test, Al-Li alloy, Microstructure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1793602 Optimization of Multifunctional Battery Structures for Mars
Authors: James A Foster, Guglielmo S Aglietti
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Multifunctional structures are a potentially disruptive technology that allows for significant mass savings on spacecraft. The specific concept addressed herein is that of a multifunctional power structure. In this paper, a parametric optimisation of the design of such a structure that uses commercially available battery cells is presented. Using numerical modelling, it was found that there exists several trade-offs aboutthe conflict between the capacity of the panel and its mechanical properties. It was found that there is no universal optimal location for the cells. Placing them close to the mechanical interfaces increases loading in the mechanically weak cells whereas placing them at the centre of the panel increases the stress inthe panel and reduces the stiffness of the structure.Keywords: Design Optimization, Multifunctional Structures, Power Storage.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1634601 A Numerical Framework to Investigate Intake Aerodynamics Behavior in Icing Conditions
Authors: Ali Mirmohammadi, Arash Taheri, Meysam Mohammadi-Amin
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One of the major parts of a jet engine is air intake, which provides proper and required amount of air for the engine to operate. There are several aerodynamic parameters which should be considered in design, such as distortion, pressure recovery, etc. In this research, the effects of lip ice accretion on pitot intake performance are investigated. For ice accretion phenomenon, two supervised multilayer neural networks (ANN) are designed, one for ice shape prediction and another one for ice roughness estimation based on experimental data. The Fourier coefficients of transformed ice shape and parameters include velocity, liquid water content (LWC), median volumetric diameter (MVD), spray time and temperature are used in neural network training. Then, the subsonic intake flow field is simulated numerically using 2D Navier-Stokes equations and Finite Volume approach with Hybrid mesh includes structured and unstructured meshes. The results are obtained in different angles of attack and the variations of intake aerodynamic parameters due to icing phenomenon are discussed. The results show noticeable effects of ice accretion phenomenon on intake behavior.Keywords: Artificial Neural Network, Ice Accretion, IntakeAerodynamics, Design Parameters, Finite Volume Method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2203600 Determination of Small Shear Modulus of Clayey Sand Using Bender Element Test
Authors: R. Sadeghzadegan, S. A. Naeini, A. Mirzaii
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In this article, the results of a series of carefully conducted laboratory test program were represented to determine the small strain shear modulus of sand mixed with a range of kaolinite including zero to 30%. This was experimentally achieved using a triaxial cell equipped with bender element. Results indicate that small shear modulus tends to increase, while clay content decreases and effective confining pressure increases. The exponent of stress in the power model regression analysis was not sensitive to the amount of clay content for all sand clay mixtures, while coefficient A was directly affected by change in clay content.
Keywords: Small shear modulus, bender element test, plastic fines, sand.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1129599 Creep Transition in a Thin Rotating Disc Having Variable Density with Inclusion
Authors: Pankaj, Sonia R. Bansal
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Creep stresses and strain rates have been obtained for a thin rotating disc having variable density with inclusion by using Seth-s transition theory. The density of the disc is assumed to vary radially, i.e. ( ) 0 ¤ü ¤ü r/b m - = ; ¤ü 0 and m being real positive constants. It has been observed that a disc, whose density increases radially, rotates at higher angular speed, thus decreasing the possibility of a fracture at the bore, whereas for a disc whose density decreases radially, the possibility of a fracture at the bore increases.Keywords: Elastic-Plastic, Inclusion, Rotating disc, Stress, Strain rates, Transition, variable density.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1739598 The Ongoing Impact of Secondary Stressors on Businesses in Northern Ireland Affected by Flood Events
Authors: Jill Stephenson, Marie Vaganay, Robert Cameron, Caoimhe McGurk, Neil Hewitt
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Purpose: The key aim of the research was to identify the secondary stressors experienced by businesses affected by single or repeated flooding and to determine to what extent businesses were affected by these stressors, along with any resulting impact on health. Additionally the research aimed to establish the likelihood of businesses being re-exposed to the secondary stressors through assessing awareness of flood risk, implementation of property protection measures and level of community resilience. Design/methodology/approach: The chosen research method involved the distribution of a questionnaire survey to businesses affected by either single or repeated flood events. The questionnaire included the Impact of Event Scale (a 15-item self-report measure which assesses subjective distress caused by traumatic events). Findings: 55 completed questionnaires were returned by flood impacted businesses. 89% of the businesses had sustained internal flooding, while 11% had experienced external flooding. The results established that the key secondary stressors experienced by businesses, in order of priority, were: flood damage, fear of reoccurring flooding, prevention of access to the premise/closure, loss of income, repair works, length of closure and insurance issues. There was a lack of preparedness for potential future floods and consequent vulnerability to the emergence of secondary stressors among flood affected businesses, as flood resistance or flood resilience measures had only been implemented by 11% and 13% respectively. In relation to the psychological repercussions, the Impact of Event scores suggested that potential prevalence of posttraumatic stress disorder (PTSD) was noted among 8 out of 55 respondents (l5%). Originality/value: The results improve understanding of the enduring repercussions of flood events on businesses, indicating that not only residents may be susceptible to the detrimental health impacts of flood events and single flood events may be just as likely as reoccurring flooding to contribute to ongoing stress. Lack of financial resources is a possible explanation for the lack of implementation of property protection measures among businesses, despite 49% experiencing flooding on multiple occasions. Therefore it is recommended that policymakers should consider potential sources of financial support or grants towards flood defences for flood impacted businesses. Any form of assistance should be made available to businesses at the earliest opportunity as there was no significant association between the time of the last flood event and the likelihood of experiencing PTSD symptoms.
Keywords: Flood event, flood resilience, flood resistance, PTSD, secondary stressors.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1784597 Non-Circular Carbon Fiber Reinforced Polymers Chainring Failure Analysis
Authors: A. Elmikaty, Z. Thanawarothon, L. Mezeix
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This paper presents a finite element model to simulate the teeth failure of non-circular composite chainring. Model consists of the chainring and a part of the chain. To reduce the size of the model, only the first 11 rollers are simulated. In order to validate the model, it is firstly applied to a circular aluminum chainring and evolution of the stress in the teeth is compared with the literature. Then, effect of the non-circular shape is studied through three different loading positions. Strength of non-circular composite chainring and failure scenario is investigated. Moreover, two composite lay-ups are proposed to observe the influence of the stacking. Results show that composite material can be used but the lay-up has a large influence on the strength. Finally, loading position does not have influence on the first composite failure that always occurs in the first tooth.
Keywords: CFRP, composite failure, FEA, non-circular chainring.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1169596 An Approach for the Prediction of Cardiovascular Diseases
Authors: Nebi Gedik
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Regardless of age or gender, cardiovascular illnesses are a serious health concern because of things like poor eating habits, stress, a sedentary lifestyle, hard work schedules, alcohol use, and weight. It tends to happen suddenly and has a high rate of recurrence. Machine learning models can be implemented to assist healthcare systems in the accurate detection and diagnosis of cardiovascular disease (CVD) in patients. Improved heart failure prediction is one of the primary goals of researchers using the heart disease dataset. The purpose of this study is to identify the feature or features that offer the best classification prediction for CVD detection. The support vector machine classifier is used to compare each feature's performance. It has been determined which feature produces the best results.
Keywords: Cardiovascular disease, feature extraction, supervised learning, support vector machine.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 170595 Practices in Planning, Design and Construction of Head Race Tunnel of a Hydroelectric Project
Authors: M. S. Thakur, Mohit Shukla
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A channel/tunnel, which carries the water to the penstock/pressure shaft is called headrace tunnel (HRT). It is necessary to know the general topography, geology of the area, state of stress and other mechanical properties of the strata. For this certain topographical and geological investigations, in-situ and laboratory tests, and observations are required to be done. These investigations play an important role in a tunnel design as these help in deciding the optimum layout, shape and size and support requirements of the tunnel. The paper includes inputs from Nathpa Jhakri Hydeoelectric project which is India’s highest capacity (1500 MW) operating hydroelectric project. The paper would help the design engineers with various new concepts and preparedness against geological surprises.Keywords: Tunnelling, geology, head race tunnel, rockmass.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3760594 Behavior Fatigue Life of Wind Turbine Rotor with Longitudinal Crack Growth
Authors: S. Lecheb, A. Nour, A. Chellil, H. Mechakra, N. Hamad, H. Kebir
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This study concerned the dynamic behavior of the wind turbine rotor. Before all we have studied the loads applied to the rotor, which allows the knowledge their effect on the fatigue, also studied the rotor with longitudinal crack in order to determine stress, strain and displacement. Firstly we compared the first six modes shapes between cracking and uncracking of HAWT rotor. Secondly we show show evolution of first six natural frequencies with longitudinal crack propagation. Finally we conclude that the residual change in the natural frequencies can be used as in shaft crack diagnosis predictive maintenance.
Keywords: Wind turbine rotor, natural frequencies, longitudinal crack growth, life time.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2197593 Determining a Suitable Maintenance Measure for Gentelligent Components Using Case-Based Reasoning
Authors: M. Winkens, P. Nyhuis
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Components with sensory properties such as gentelligent components developed at the Collaborative Research Centre 653 offer a new angle in terms of the full utilization of the remaining service life as well as preventive maintenance. The developed methodology of component status driven maintenance analyzes the stress data obtained during the component's useful life and on the basis of this knowledge assesses the type of maintenance required in this case. The procedure is derived from the case-based reasoning method and will be explained in detail. The method's functionality is demonstrated with real-life data obtained during test runs of a racing car prototype.
Keywords: Gentelligent Components, Preventive Maintenance, Case based Reasoning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1905592 Effect of Mineral Ion Addition on Yeast Performance during Very High Gravity Wort Fermentation
Authors: H. O. Udeh, T. E. Kgatla, A. I. O. Jideani
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The effect of Zn2+, Mg2+, and Ba2+ on Saccharomyces pastorianus performance was evaluated in this study at independent and three variable combinations. After 96 h of fermentation, high wort fermentability (%F) = 29.53 was obtained in medium containing 900:4 ppm Mg2+ + Ba2+. Increased ethanol yield 7.35 %(v/v) and 7.13 %(v/v) were obtained in media containing 900:4 ppm Mg2+ + Ba2+ and 12:900 ppm Zn2+ + Mg2+. Decrease %F = 22.54 and ethanol yield 6.18 % (v/v) was obtained in medium containing 12:4 ppm Zn2+ + Ba2+. In media containing the individual ions, increased %F = 27.94 and 26.03 were recorded for media containing 700 ppm Mg2+ and 2 ppm Ba2+ , with ethanol yield of 7.88% (v/v) and 7.62% (v/v) respectively. Reduced %F and ethanol yield was observed for 10 ppm Zn2+ and 4 ppm Ba2+ media. The impact of Ba2+ at 1 and 2 ppm was significant.
Keywords: Ethanol yield, fermentability, mineral ions, yeast stress, very high gravity fermentation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3017591 Developing a Coronavirus Academic Paper Sorting Application
Authors: Christina A. van Hal, Xiaoqian Jiang, Luyao Chen, Yan Chu, Robert D. Jolly, Yaobin Lin, Jitian Zhao, Kang Lin Hsieh
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The COVID-19 Literature Summary App, now live on the university website, was created for the primary purpose of enabling academicians and clinicians to quickly sort through the vast array of recent coronavirus publications by topics of interest. Multiple methods of summarizing and sorting the manuscripts were created. A summary page introduces the application function and capabilities, while an interactive map provides daily updates on infection, death, and recovery rates. A page with a pivot table allows publication sorting by topic, with an interactive data table that allows sorting topics by columns, as wells as the capability to view abstracts. Additionally, publications may be sorted by the medical topics they cover. We used the CORD-19 database to compile lists of publications. The data table can sort binary variables, allowing the user to pick desired publication topics, such as papers that describe COVID-19 symptoms. The application is primarily designed for use by researchers but can be used by anybody who wants a faster and more efficient means of locating papers of interest.
Keywords: COVID-19, literature summary, information retrieval, snorkel
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 469590 Frictionless Contact Problem Between Two Orthotropic Elastic Layers
Authors: V. Kahya, A. Birinci, R. Erdol
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A frictionless contact problem for a two-layer orthotropic elastic medium loaded through a rigid flat stamp is considered. It is assumed that tensile tractions are not allowed and only compressive tractions can be transmitted across the interface. In the solution, effect of gravity is taken into consideration. If the external load on the rigid stamp is less than or equal to a critical value, continuous contact between the layers is maintained. The problem is expressed in terms of a singular integral equation by using the theory of elasticity and the Fourier transforms. Numerical results for initial separation point, critical separation load and contact stress distribution are presented.Keywords: Frictionless contact, Initial separation, Orthotropicmaterial, Singular integral equation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1812589 The Effects of the Inference Process in Reading Texts in Arabic
Authors: May George
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Inference plays an important role in the learning process and it can lead to a rapid acquisition of a second language. When learning a non-native language i.e., a critical language like Arabic, the students depend on the teacher’s support most of the time to learn new concepts. The students focus on memorizing the new vocabulary and stress on learning all the grammatical rules. Hence, the students became mechanical and cannot produce the language easily. As a result, they are unable to predicate the meaning of words in the context by relying heavily on the teacher, in that they cannot link their prior knowledge or even identify the meaning of the words without the support of the teacher. This study explores how the teacher guides students learning during the inference process and what are the processes of learning that can direct student’s inference.Keywords: Inference, Reading, Arabic, and Language Acquisition.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2052588 Exploring the Challenges to Usage of Building and Construction Cost Indices in Ghana
Authors: J. J. Gyimah, E. Kissi, S. Osei-Tutu, C. D. Adobor, T. Adjei-Kumi, E. Osei-Tutu
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Price fluctuation contract is imperative and of paramount essence in the construction industry as it provides adequate relief and cushioning for changes in the prices of input resources during construction. As a result, several methods have been devised to better help in arriving at fair recompense in the event of price changes. However, stakeholders often appear not to be satisfied with the existing methods of fluctuation evaluation, ostensibly because of the challenges associated with them. The aim of this study was to identify the challenges to usage of building construction cost indices in Ghana. Data were gathered from contractors and quantity surveying firms. The study utilized survey questionnaire approach to elicit responses from the contractors and the consultants. Data gathered were analyzed scientifically, using the Relative Importance Index (RII) to rank the problems associated with the existing methods. The findings revealed the following among others: late release of data; inadequate recovery of costs; and work items of interest not included in the published indices as the main challenges of the existing methods. Findings provided useful lessons for policy makers and practitioners in decision making towards the usage and improvement of available indices.
Keywords: Building construction cost indices, challenges, usage, Ghana.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 625587 Three-Dimensional Generalized Thermoelasticity with Variable Thermal Conductivity
Authors: Hamdy M. Youssef, Mowffaq Oreijah, Hunaydi S. Alsharif
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In this paper, a three-dimensional model of the generalized thermoelasticity with one relaxation time and variable thermal conductivity has been constructed. The resulting non-dimensional governing equations together with the Laplace and double Fourier transforms techniques have been applied to a three-dimensional half-space subjected to thermal loading with rectangular pulse and traction free in the directions of the principle co-ordinates. The inverses of double Fourier transforms, and Laplace transforms have been obtained numerically. Numerical results for the temperature increment, the invariant stress, the invariant strain, and the displacement are represented graphically. The variability of the thermal conductivity has significant effects on the thermal and the mechanical waves.
Keywords: Thermoelasticity, three-dimensional, Laplace transforms, Fourier transforms, thermal conductivity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 749586 Treatment of Wastewater from Wet Scrubbers in Secondary Lead Smelters for Recycling and Lead Recovery
Authors: Mahmoud A. Rabah
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The present study shows a method to recover lead metal from wastewater of wet scrubber in secondary lead smelter. The wastewater is loaded with 42,000 ppm of insoluble lead compounds (TSP) submicron in diameter. The technical background benefits the use of cationic polyfloc solution to flocculate these colloidal solids before press filtration. The polymer solution is injected in the wastewater stream in a countercurrent flow design. The study demonstrates the effect of polymer dose, temperature, pH, flow velocity of the wastewater and different filtration media on the filtration extent. Results indicated that filtration rate (¦r), quality of purified water, purifying efficiency (¦e) and floc diameter decrease regularly with increase in mass flow rate and velocity up to turbulence of 0.5 m.sec-1. Laminar flow is in favor of flocculation. Polyfloc concentration of 0.75 – 1.25 g/m3 wastewater is convenient. Increasing temperature of the wastewater and pneumatic pressure of filtration enhances ¦r. High pH value deforms floc formation and assists degradation of the filtration fabric. The overall efficiency of the method amounts to 93.2 %. Lead metal was recovered from the filtrate cake using carbon as a reducing agent at 900°C.
Keywords: Wastewater, wet scrubbers, filtration, secondary lead.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3443585 The Estimation of Semi Elliptical Surface Cracks Advancement via Fuzzy Logic
Authors: Gürol Önal, Ahmet Avcı
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This paper presented the results of an experimental investigation into the axial fatigue behavior of a 5086 aluminum alloy which have several notch-aspect ratios a0/c0 and notch thickness ratio a/t with semi-elliptical surface cracks. Tests were conducted in la b air for stress levels of 50 % of their yield strength. Experiments were carried out for various notch to thickness ratios. Crack growth rates of test specimens both in surface and depth directions were determined by using die penetration method. Fuzzy Logic method was used to predict the deep direction crack growth because the dept of the crack is considerably difficult to measure.Keywords: Axial fatigue, Crack growth rate, surface crack, Al-Mg alloy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1682584 Finite Difference Method of the Seismic Analysis of Earth Dam
Authors: Alaoua Bouaicha, Fahim Kahlouche, Abdelhamid Benouali
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Many embankment dams have suffered failures during earthquakes due to the increase of pore water pressure under seismic loading. After analyzing of the behavior of embankment dams under severe earthquakes, major advances have been attained in the understanding of the seismic action on dams. The present study concerns numerical analysis of the seismic response of earth dams. The procedure uses a nonlinear stress-strain relation incorporated into the code FLAC2D based on the finite difference method. This analysis provides the variation of the pore water pressure and horizontal displacement.Keywords: Earthquake, numerical analysis, FLAC2D, displacement, Embankment Dam, pore water pressure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2451583 A New Strategy for Minimizing Precipitations during ASP Flooding in Carbonate Reservoirs
Authors: Khaled Abdalla Elraies, Shuaib Ahmed
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A large quantity of world-s oil reserves exists in carbonate reservoirs. Carbonate reservoirs are very sensitive to chemical enhanced oil recovery process because of containing large amount of calcite, dolomite and calcium sulfate minerals. These minerals cause major obstacles during alkali-surfactant-polymer (ASP) flooding. Alkali reacts with these minerals and form undesired precipitations which plug effective porous openings, reduce permeability and cause scale occurrence at the wellbore. In this paper, a new chemical combination consists of acrylic acid and alkali was used to minimize precipitation problem during ASP flooding. A series of fluid-fluid compatibility tests were performed using acrylic acid and different concentrations of alkaline. Two types of alkalis namely; sodium carbonate and sodium metaborate were screened. As a result, the combination of acrylic acid and sodium carbonate was not effective in preventing calcium and magnesium precipitations. However, acrylic acid and sodium metaborate showed promising results for keeping all solutions without any precipitations. The ratio of acrylic acid to sodium metaborate of 0.7:1.0 was found to be optimum for achieving a compatible solution for 30 days at 80oC.Keywords: Fluid-fluid compatibility test, Carbonate reservoirs, Precipitations and ASP flooding.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2752582 Design of Stainless Steel Implant for Fractured Distal Femur
Authors: Abhishek Soni, Bhagat Singh
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Perfect restoration of fractured distal femur has been a challenging task for the medical practitioners. In the present study, model of a fractured bone has been created using the scan data of the damaged bone. Thereafter, customized implant of Stainless Steel (SS-316L) for this fractured femur bone is modeled using the reverse engineering approach. Clinical set-up is prepared by assembling all the models together. Stress and deformation analysis of this clinical set-up has been performed in order to check the load bearing capacity and intactness of the joint. From this analysis, it has been inferred that the stresses and deformation developed due to the static load of the person is within the permissible limits.
Keywords: Biomechanical evaluations, customized implant, reverse engineering, stainless steel alloy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 811581 Gas Lift Optimization to Improve Well Performance
Authors: Mohamed A. G. H. Abdalsadig, Amir Nourian, G. G. Nasr, Meisam Babaie
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Gas lift optimization is becoming more important now a day in petroleum industry. A proper lift optimization can reduce the operating cost, increase the net present value (NPV) and maximize the recovery from the asset. A widely accepted definition of gas lift optimization is to obtain the maximum output under specified operating conditions. In addition, gas lift, a costly and indispensable means to recover oil from high depth reservoir entails solving the gas lift optimization problems. Gas lift optimization is a continuous process; there are two levels of production optimization. The total field optimization involves optimizing the surface facilities and the injection rate that can be achieved by standard tools softwares. Well level optimization can be achieved by optimizing the well parameters such as point of injection, injection rate, and injection pressure. All these aspects have been investigated and presented in this study by using experimental data and PROSPER simulation program. The results show that the well head pressure has a large influence on the gas lift performance and also proved that smart gas lift valve can be used to improve gas lift performance by controlling gas injection from down hole. Obtaining the optimum gas injection rate is important because excessive gas injection reduces production rate and consequently increases the operation cost.
Keywords: Optimization, production rate, reservoir pressure effect, gas injection rate effect, gas injection pressure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6800580 Anisotropic Constitutive Model and its Application in Simulation of Thermal Shock Wave Propagation for Cylinder Shell Composite
Authors: Xia Huang, Wenhui Tang, Banghai Jiang, Xianwen Ran
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In this paper, a plane-strain orthotropic elasto-plastic dynamic constitutive model is established, and with this constitutive model, the thermal shock wave induced by intense pulsed X-ray radiation in cylinder shell composite is simulated by the finite element code, then the properties of thermal shock wave propagation are discussed. The results show that the thermal shock wave exhibit different shapes under the radiation of soft and hard X-ray, and while the composite is radiated along different principal axes, great differences exist in some aspects, such as attenuation of the peak stress value, spallation and so on.Keywords: anisotropic constitutive model, thermal shock wave, X-ray, cylinder shell composite.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1756579 Effect of Fractional Flow Curves on the Heavy Oil and Light Oil Recoveries in Petroleum Reservoirs
Authors: Abdul Jamil Nazari, Shigeo Honma
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This paper evaluates and compares the effect of fractional flow curves on the heavy oil and light oil recoveries in a petroleum reservoir. Fingering of flowing water is one of the serious problems of the oil displacement by water and another problem is the estimation of the amount of recover oil from a petroleum reservoir. To address these problems, the fractional flow of heavy oil and light oil are investigated. The fractional flow approach treats the multi-phases flow rate as a total mixed fluid and then describes the individual phases as fractional of the total flow. Laboratory experiments are implemented for two different types of oils, heavy oil, and light oil, to experimentally obtain relative permeability and fractional flow curves. Application of the light oil fractional curve, which exhibits a regular S-shape, to the water flooding method showed that a large amount of mobile oil in the reservoir is displaced by water injection. In contrast, the fractional flow curve of heavy oil does not display an S-shape because of its high viscosity. Although the advance of the injected waterfront is faster than in light oil reservoirs, a significant amount of mobile oil remains behind the waterfront.
Keywords: Fractional flow curve, oil recovery, relative permeability, water fingering.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1473