Abstract
The current study attempts to discuss the effects of viscosity and locality on a fiber-reinforced thermoelastic solid. The problem is solved analytically in the context of the three-phase-lag model as well as the GreenNaghdi theory without energy dissipation (G-N II). The method of normal mode analysis is used to obtain analytical expressions for the displacement, stress, and temperature distributions. Compute the physical fields with suitable boundary conditions and perform numerical calculations using MATLAB programming. Comparisons are carried out with the results in the absence and presence of locality as well as viscosity. The locality and viscosity have great effects on all considered physical fields since the amplitudes of these quantities are vary. This procedure remains valid when a nonlocal elastic solid is replaced with an elastic one.
Key Words
nonlocal fiber-reinforced; three-phase lag-model; visco-thermoelastic
Address
Department of Mathematics, Faculty of Science, Zagazig University, P.O. Box 44519,Zagazig, Egypt
Abstract
Biocompositesmade up of starch and jute fibres are biodegradable and environmentally friendly materials
for sustainable development. In this study, corn starch has been separately modified with 15% pine rosin and 40%
glutaraldehyde, and 30% glycerol is used as a plasticizer. The composites have been prepared for three different volume proportions of matrix and jute fibre such as 60:40, 70:30 and 80:20 by using a hot compression moulding machine. The effects of pine rosin and glutaraldehyde on mechanical properties have been studied. Pine rosin modified starch jute composites have shown higher tensile and flexural properties as compared with glutaraldehyde modified starch jute composite. The highest tensile strength and modulus are found at 60:40 matrix and jute fibre volume proportion of pine rosin modified starch jute composite which are 13.97 MPa and 782.94 MPa respectively. Similar trends were found in flexural strength and modulus for pine rosin modified starch jute composite having matrix to jute fibre proportion 60:40 which are 29.18 MPa and 1107.76 MPa respectively. But, in case of impact strength, glutaraldehyde modified starch jute composite having matrix to jute fibre proportion 80:20 have shown highest impact strength that is 59.05 KJ/m2. Starch-jute composite with glutaraldehyde shows 33% more water absorbency as compared to composite having pine rosin as cross linker. Highest FTIR graph indicates that the number of -OH group is much lower in case of pine rosin modified starch than glutatraldehyde modified starch which indicates that bonds formed by pine rosin are much stronger than the bonds formed by glutaraldehyde. The surface morphology of the composite was influenced by pine rosin and glutaraldehyde which is shown in the SEM image.
Key Words
biocomposite; corn; glutaraldehyde; jute fibre; pine rosin; starch
Address
Textile Manufactures Department, Veermata Jijabai Technological Institute, Mumbai, 400019, India
Abstract
The theory of nonlinear elastic wave propagation is important in multiple scientific and engineering fields.
In this study, we present a comprehensive examination of nonlinear elastic wave profiles through a contemporary
approach of successive approximation. This research is related to nonlinear elastic wave models along different types of nonlinearities. Murnaghan potential is used due to the assumption of the hyper-elastic materials. We explore the complication of the governing equations and go through the behaviors of nonlinear waves in one dimension. The comparative aspect of our study is a distinctive feature, as we evaluate and contrast the results obtained using successive approximation along different nonlinearities. Additionally, we present graphical representations of our findings, enhancing the visual comprehension of the wave profiles and their evolution. This study contributes to the nonlinear elastic wave analysis and comparison.
Key Words
Murnaghan's potential; nonlinear elasticity; second harmonic generation; successive approximation method
Address
Abdus Salam School of Mathematical Sciences, Government College University, Lahore-54000, Pakistan
Abstract
Due to higher strength-to-weight ratio of composite laminates, they find uses in many weight-sensitive applications like aerospace, automobile and marine structures. From a reliability point of view, accurate prediction of failure of these structures is important. Due to the complexities in the manufacturing processes of composite laminates, there is a variation in the material properties and geometric parameters. Hence stochastic aspects are important while designing the composite laminates. Many existing works of composite laminate failure analysis are based on the deterministic approach but it is important to consider the randomness in the material properties, geometry and loading to predict accurate failure loads. In this paper the statistics of the ultimate failure load of the [0/ϑ]s laminated composite plate (LCP) containing the edge crack and voids subjected to the tensile loading are presented in terms of the mean and coefficient of variance (COV). The objective is to better the efficacy of laminate failure by predicting the statistics of the ultimate failure load of LCP with random material, geometric and loading parameters. The stochastic analysis is done by using the extended finite element method (XFEM) combined with the second-order perturbation technique (SOPT). The ultimate failure load of the LCP is obtained by ply-by-ply failure analysis using the ply discount method combined with the Tsai-Wu failure criterion. The aim is to know the effect of the stacking sequence, crack length, crack angle, location of voids and number of voids on the mean and corresponding COV of the ultimate failure load of LCP is investigated. The results of the ultimate failure load obtained by the present method are in good agreement with the existing experimental and numerical results. It is observed that [0/ϑ]s LCPs are very sensitive to the randomness in the crack length, applied load, transverse tensile strength of the laminate and modulus of elasticity of the material, so precise control of these parameters is important. The novelty of the present study is, the stochastic implementation in XFEM for the failure prediction of LCPs containing crack and voids.
Key Words
coefficient of variance; crack; SOPT; stochastic; voids; XFEM
Address
Ashok B. Magar: Department of Mechanical Engineering, N.K.Orchid College of Engineering and Technology, Solapur 413002, India
Achchhe Lal: Department of Mechanical Engineering, S. V. National Institute of Technology, Surat 395007, India
Abstract
The paper is a study on the biothermoelastic analysis in viscoelastic biological tissues in the presence of thermal relaxation times. Using Laplace transforms and related methodologies, we explore how living tissue responds to an exponentially decaying pulse of heat flux at the boundary. The Laplace transformations are reversed using the numerical method. The Tzuo technique was used to measure the reversal. Temperature, displacement, and stress distributions are affected by single-phase and delay relaxation coefficients as well as volume rheological factors, are provided with numerical findings and graphically depicted. In addition, we carry out a parametric analysis to provide assistance in choosing the design variables that are the most successful, which finally results in an improvement in the
accuracy of hyperthermia treatments.
