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Modeling and Analysis of Composite Bonded Joints
Miller Park,
Kelly Frey,
Lion Simon
Issue:
Volume 2, Issue 1, January 2017
Pages:
1-7
Received:
29 October 2016
Accepted:
15 November 2016
Published:
16 December 2016
Abstract: The bonded joints in composite structures is a challenging point in both research study and industry application. Compared with homogeneous and isotropic material, there is higher chance of stress concentration and intrinsic weak for this anisotropic structures. It is most common source of failure in structural laminates. So it is important to model and analyze the composite bonded joint to get the mechanical response and estimate the damage evolution. In this review paper, composite bonded joint are categorized based on bonded methods, materials, loading methods and failure modes. Multiple widely used adhesive bonded joint models including cohesive zone element model (CZM), interface element model, multiple point constraint model, kinking crack model, and repeating RVE model are introduced and discussed. To estimate the damage evolution in the bonded joint, a series of damage criteria have been developed including displacement based, stress based, energy based and modulus based damage criteria. Those damage criteria of bonded joint are also discussed and compared. This review work is important for the development of modeling of composite bonded joint in future.
Abstract: The bonded joints in composite structures is a challenging point in both research study and industry application. Compared with homogeneous and isotropic material, there is higher chance of stress concentration and intrinsic weak for this anisotropic structures. It is most common source of failure in structural laminates. So it is important to mode...
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Hydrodynamic Study Using CFD Simulations in a Horizontal Two-Phase Flow Through Sudden Contraction
Ibtissem Belgacem,
Y. Salhi,
E-K. Si-Ahmed
Issue:
Volume 2, Issue 1, January 2017
Pages:
8-16
Received:
31 October 2016
Accepted:
29 November 2016
Published:
26 December 2016
Abstract: Two-phase flows are encountered in a wide range of industrial application. In the present work, two-phase computational fluid dynamics (CFD) calculations, using Eulerian–Eulerian model and commercial CFD package FLUENT 6.3, were employed to calculate pressure drops caused by abrupt flow area contraction in small circular pipes for two-phase flow of air and water mixtures at room temperature and near atmospheric pressure. The pressure drop is determined by extrapolating the computed pressure profiles upstream and downstream of the contraction. Variables studied include: gas and liquid velocities, and pipe contraction ratio. The numerical results were validated against experimental data from the literature and are found to be in good agreement. Our findings could be useful in designing pipeline.
Abstract: Two-phase flows are encountered in a wide range of industrial application. In the present work, two-phase computational fluid dynamics (CFD) calculations, using Eulerian–Eulerian model and commercial CFD package FLUENT 6.3, were employed to calculate pressure drops caused by abrupt flow area contraction in small circular pipes for two-phase flow of...
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Theoretical and Experimental Investigation of Hydromechanical Extrusion Process
Olesya Yurevna Agapitova,
Sergey Vasilievich Byvaltsev,
Alexander Georgievich Zalazinski
Issue:
Volume 2, Issue 1, January 2017
Pages:
17-23
Received:
26 October 2016
Accepted:
17 November 2016
Published:
29 December 2016
Abstract: The theoretical and experimental investigation of the process of hydromechanical extrusion (HE) of aluminum alloys Al 5056 was carried out. The aim is to determine the optimal parameters of this process. These parameters were determined to minimize the extrusion force and damage factor of a workpiece by using explicit finite elements method. The results were presented in a visual form and were shown that use of active friction forces reduces the extrusion force. Statistical processing of the experimental data gave regression equations for definition the damage factor and the value of the specific extrusion stress.
Abstract: The theoretical and experimental investigation of the process of hydromechanical extrusion (HE) of aluminum alloys Al 5056 was carried out. The aim is to determine the optimal parameters of this process. These parameters were determined to minimize the extrusion force and damage factor of a workpiece by using explicit finite elements method. The re...
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Effects of Thermal, Physical, and Chemical Properties of Biodiesel and Diesel Blends
Sayyed Siraj,
Renuka Kale,
Swapnil Deshmukh
Issue:
Volume 2, Issue 1, January 2017
Pages:
24-31
Received:
5 October 2016
Accepted:
28 October 2016
Published:
29 December 2016
Abstract: The biodiesels are the fuels composed of mono-alkyl esters of long chain fatty acids derived from the renewable energy sources, such as vegetable oil, animal fat, etc. The thermogravimetric analysis (TGA) from thermal, density and viscosity from physical and iodine value from the chemical properties has been considered for the study, by considering this objective the literature review was done through the research papers of last two decades. The conclusions drawn are as follows, the thermal property TGA is an important property which shows the distillation and decomposition, and it provides behavioural information of a substance are measured as a function of temperature. The density and viscosity from the physical properties for different biodiesel strongly affect the fuel consumptions of engine system and it has been seen that density and viscosity strongly dependent on the temperature. The iodine value from chemical properties, the iodine value for different biodiesel and diesel blends increases as the biodiesel fractions increases in the blends.
Abstract: The biodiesels are the fuels composed of mono-alkyl esters of long chain fatty acids derived from the renewable energy sources, such as vegetable oil, animal fat, etc. The thermogravimetric analysis (TGA) from thermal, density and viscosity from physical and iodine value from the chemical properties has been considered for the study, by considering...
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Efficiency of a Coal Fired Boiler in a Typical Thermal Power Plant
Gudimella Tirumala Srinivas,
Doddapineni Rajeev Kumar,
Peruri Venkata Vithal Murali Mohan,
Boggarapu Nageswara Rao
Issue:
Volume 2, Issue 1, January 2017
Pages:
32-36
Received:
14 October 2016
Accepted:
21 November 2016
Published:
3 January 2017
Abstract: This paper presents briefly on the boiler efficiency evaluation procedures by direct and indirect methods useful in thermal power plants. In the direct method consideration is given to the amount of heat utilized while evaluating the efficiency of the boiler, whereas, indirect method accounts for various heat losses. The boiler efficiency evaluated by direct method is found to be lower than that evaluated by indirect method as per the ASME PTC-4.1 standards. However, the direct method helps the plant personnel to evaluate quickly the boiler efficiency with few parameters and less instrumentation.
Abstract: This paper presents briefly on the boiler efficiency evaluation procedures by direct and indirect methods useful in thermal power plants. In the direct method consideration is given to the amount of heat utilized while evaluating the efficiency of the boiler, whereas, indirect method accounts for various heat losses. The boiler efficiency evaluated...
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Stress Analysis of Traverse Beam Crane Hook Used in Steel Melting Shops of Steel Plant by ANSYS and CATIA
K. S. Raghu Ram,
D. Ajay Kumar
Issue:
Volume 2, Issue 1, January 2017
Pages:
37-40
Received:
14 September 2016
Accepted:
21 November 2016
Published:
3 January 2017
Abstract: The crane hook is fabricated with eight plates of 25 mm thickness and cut to the required size and dimensions as shown in the figure. The plates are riveted. Each crane hook carries 125 tones load. For this load the stress is found to be high and so high carbon steel with higher yield strength is suggested. After analyzing with different materials, a material is confirmed to be used for the manufacturing the crane hook. High Carbon Steel is suggested to be used as the material which is having high yield strength. A number of materials and designs are chosen for the use of crane hook, but from the different materials like Carbon steel, Cast Steel, SAE 1025Water quenched, SAE 1096 Oil Quenched steel and Stainless steel. Finally Carbon steel give the optimized results and the material is finalized for the fabrication purpose and the crane is working safely without any interruption since three years.
Abstract: The crane hook is fabricated with eight plates of 25 mm thickness and cut to the required size and dimensions as shown in the figure. The plates are riveted. Each crane hook carries 125 tones load. For this load the stress is found to be high and so high carbon steel with higher yield strength is suggested. After analyzing with different materials,...
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Effects of Surface Pre-treatment on the Nitrided Layers Properties
Mohamed Ali Terres,
Brahim Ben Fathallah,
Abdelkarim Ghanem
Issue:
Volume 2, Issue 1, January 2017
Pages:
41-47
Received:
12 August 2016
Accepted:
25 August 2016
Published:
4 January 2017
Abstract: In this work the 42CrMo4 steel ground surface integrity was evaluated at different grinding conditions before and after nitriding. An experimental study was carried out to investigate the influence of depth of cut on work piece surface integrity by grinding. Surface integrity was characterized by roughness, micro-hardness, residual stress distribution and ground surface morphology. These properties were compared to nitriding state. These improvements in grindability and in surface integrity are particularly favoured by low depth of cut values. It is also shown that these improvements are essentially due to the reduction of the grinding temperature, which decrease the tensile residual stresses and favours the material removal by shearing and limits the ground surface damage. The roughness of the ground work piece surfaces increases with the depth of cut, which was attributed to plastically deformed coatings on the work piece surface occurring with elevated temperature. The results presented in this study shows that the material history before nitriding does not have any influence on the residual stresses distribution after nitriding. This is due to that during the nitriding treatment, especially in the heating phase; the tensile stresses generated by grinding are cancelled under the temperature effect.
Abstract: In this work the 42CrMo4 steel ground surface integrity was evaluated at different grinding conditions before and after nitriding. An experimental study was carried out to investigate the influence of depth of cut on work piece surface integrity by grinding. Surface integrity was characterized by roughness, micro-hardness, residual stress distribut...
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Mathematical Modeling of Self-Oscillations in a Rijke’s Tube with Variable Heat Flow Power
Boris Basok,
Vladimir Gotsulenko
Issue:
Volume 2, Issue 1, January 2017
Pages:
48-53
Received:
19 September 2016
Accepted:
29 September 2016
Published:
12 January 2017
Abstract: In this paper the mathematical model of self - oscillation in Rijke's tube is found. We introduce the characteristic of the pressure of the heat supply. Using the energy equation in the form of the first law of thermodynamics to flow defined mechanisms of thermoacoustic instability in this problem. Using the pressure characteristic of the supply of heat and the classical Lyapunov’s theory of stability defines the conditions for self-excitation of oscillation. It was found that when the increasing combustion delay the harmonic self-oscillations of the "singing" flame are converted to the relaxation oscillations.
Abstract: In this paper the mathematical model of self - oscillation in Rijke's tube is found. We introduce the characteristic of the pressure of the heat supply. Using the energy equation in the form of the first law of thermodynamics to flow defined mechanisms of thermoacoustic instability in this problem. Using the pressure characteristic of the supply of...
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