Specific features of thermal deforming of composite inductors during magnetic-pulse processing of materials

The problem of taking into account a non-stationary inhomogeneous temperature field in the analysis of the stress-strain state of inductor systems for magnetic-pulse processing of materials is considered. It follows from the analysis of open information sources that the problem of analyzing a non-stationary temperature field arising from the presence of a non-uniform electromagnetic field and its effect on deformation has been sufficiently studied in relation to induction heating. At the same time, during other operations of magnetic-pulse processing of materials, heating of equipment can cause additional deformations of a significant magnitude, which, in turn, can lead to a loss of equipment performance due to destruction or irreversible deformation. A general approach to the analysis of such problems is proposed, which involves the determination of the spatial-temporal distributions of the quantitative characteristics of the electromagnetic field, temperature field and stress-strain state. The necessity of using numerical methods for carrying out such an analysis has been substantiated. The most effective numerical method is the finite element method, which makes it possible to analyze the unsteady electromagnetic field, temperature field, and stress-strain state within the same calculation scheme. In this case, within the framework of the finite element method, iterative schemes can be created that allow taking into account nonlinear effects. Here, nonlinear effects can be due to the dependence of the mechanical and electro-physical properties of the material on temperature, the plastic nature of deformation, and the need to take into account contact phenomena. The results of complex analysis for a composite single-turn inductor with a dielectric band are presented. The features of contact interaction were taken into account by introducing layers of contact finite elements. The stress-strain state of the inductor is estimated for two variants of the materials used: copper and non-magnetic steel.

Endosulfan insecticide removal planning with bioaugmentation-landfarming bioremediation method

Endosulfan is a toxic organochlorine insecticide and is persistent in the environment. Endosulfan residue can be accumulated underground and lower soil quality, pollute water sources, and create bioaugmentation. This research aims to gather required information and study the potential of bacteria consortium consists of Bordetella sp., Bordetella petrii, and Achromobactery xylosoxidans to remediate endosulfan polluted soil. Bioremediation on laboratory scale conducted in a soil reactor, the pH level of 7, 20% humidity, and adjusted temperature to field temperature. Endosulfan was added into a reactor with a concentration of 2mg/g. The bacteria consortium utilized endosulfan as a nutrient source to decently grow up until this research was finished on the 30th day. Maximum removal occurred on upper layer soil with 99% of alpha-endosulfan and beta-endosulfan removal rates. Pilot-scale removal can be implemented with landfarming bioremediation. Two (2) processing beds were prepared with 15m of length, 7.5m of width, and 0.5m of height. This method was able to remove 99% of endosulfan in just 457.75 hours. This research can be implemented to remediate endosulfan polluted soil through the bioremediation method by utilizing bacteria consortium.

A 2D Numerical Simulation of Binary Alloy Solidification: Effect of Mesh Resolution on Formation of Channel Segregates

Mesh refinement is crucial for capturing the complex phenomena that governs the formation of channel segregates during binary alloy solidification. In this article, the influence of mesh size on the formation of channel segregates during the solidification of Sn-5wt%Pb alloy is numerically investigated. A solver is developed in OpenFOAM for solving the coupled transport equations of mass, momentum, energy and species. Subsequently, the simulations are performed for different mesh sizes to predict the flow field, temperature, species and solid fraction distribution including the morphology of channel segregates. From this study, it is observed that the mesh size significantly affects the morphology and the strength of channel segregates. For very fine mesh size, having sufficient number of grid point along their width, the formed channels are more continuous and the flow inside channels is resolved.

Boundary Layer Flow and Heat Transfer Analysis by Using the Correlation Coefficient and Regression Model Over a Stretching Bullet-Shaped Object

The boundary layer theory is important when fluid flows over a solid surface that is moving or stationary. In presence of the boundary layer, the effective shape of the body may change leading to changes in pressure distribution, as a result, the overall lift and drag forces change. Therefore, the Boundary layer theory helps in designing aerofoil’s, to compute the lift and drag forces for the aerospace and automobile designers, to control the heat transfer rate from the device, etc. So, the present problem will help design the various types of bullet-shaped objects in the field of automobile engineering. Therefore, the current problem has focused on the two-dimensional axisymmetric BL flow over a stretching bullet-shaped object for the effect of magnetic field strength (M), linear stretching parameter (M), and surface thickness parameter (s). Therefore, the main goal of this work is to determine the relation by applying the correlation coefficient among the physical parameters and velocity field, temperature field, shear stress (τw), Nusselt number (Nux). Hence, the novelty of the current paper is to develop the relationship among the dependent and independent parameters by the correlation coefficient and also developed the numerical method to solve these highly nonlinear equations. The numerical results are discussed for the three different values of the stretching ratio parameter and two values of the surface thickness parameter. The velocity and temperature distribution equations are compressed into a system of ODEs with similarity transformations. These ODEs are then solved using a spectral quasi-linearization method (SQLM) by applying Taylor series expansions that can be used to linearize the non-linear terms in the equations. These resulting linearized systems of equations are determined by the spectral collocation method. The convergence of the numerical solutions was performed by using the residual error of the PDEs. The error analysis is established for the validity of the present model. This error norm is applied to establish the validity and convergence of the numerical solution. The outcome of the mentioned dimensionless parameters over the fluid velocity field, temperature field, skin friction coefficient (Cf), and Nusselt number (Nux) are displayed graphically. It is observed that the parameters M and M are positively correlated with fluid velocity distribution within the BL but the surface thickness parameter(s) are negatively correlated. The rate of temperature increases for the parameter M and Pr but decreases for M and s. Therefore, the boundary layer thickness reduces for increasing the values of M and M but increases for increasing the values of s. The velocity of the fluid is about 80% higher in the case of a thinner surface (s = 0.2) than the thicker surface (s = 2.0) and the heat transfer rate is also igher in the case of a thinner surface comparatively thicker surface. The innovation of this present problem lies in the unification of more physical parameters into the governing equations and an attempt to give a thorough analysis of how the flow properties are affected by these parameters.