S. Chattopadhyay

Bio: S. Chattopadhyay is an academic researcher from Villanova University. The author has contributed to research in topics: Dynamometer & Magneto. The author has an hindex of 1, co-authored 1 publications receiving 315 citations.

Materialistic suitability analysis for cutting dynamometers

Abstract: Suitability of material comes forth in deciding for the right material together with the shape and size of the dynamometer to support the cutting load. Role of material strength with the size of dynamometer came into decision when fixing the maximum cutting load on the assembly parts in the same way as role of shape of deforming element came into decision when setting up the maximum permissible deformation taken up by the dynamometer. Present work aims at verifying the selection of the size, shape and material under a target cutting load that are used by various researchers in designing the cutting dynamometers successfully. Research has been done to devise cutting dynamometers with varying shapes and sizes of deforming elements made with different materials. SOLIDWORKS is employed to model the material deformation and study is conducted to compare the values obtained for the maximum deflection, strain and total von-Mises stress developed at the most heavily stressed point through SOLIDWORKS with the corresponding theoretical or experimental values obtained by the researchers.

Solid-state welding and its applications: A methodological review

Abstract: Solid-state welding refers to the joining of similar and dissimilar materials below their melting temperature. In this process, the weld formation occurs due to the intermolecular diffusion in which the interface molecules of workpieces flow from higher concentration regions to lower concentration regions due to applied pressure. The joints assembled by solid-state processes have been considered free from solidification defects, including gas porosity, hot cracking, and non-metallic inclusion. The solid-state welding process is also called state bonding. It covers various strategies such as ultrasonic welding, forges welding, diffusion welding, friction welding, explosion welding, hot welding, roll welding, and pressure welding, etc. In these, the relationship has been captured through the methods such as distortion and propagation at certain heat with mechanical energy, thermal energy, and electrical energy, etc. Solid-state welding is used in various mechanical industries. It is mostly used in the aerospace and marine field to produce weldments and is also used in the space industry, automobile industry, and aeronautic industries, etc. The present manuscript aims to discuss the process of solid-state welding and its applications with a detailed review.

Damage caused by magnetic pressure at high trapped field in quasi-permanent magnets composed of melt-textured YBaCuO superconductor

Abstract: Quasi-permanent magnets made of melt-textured YBa2Cu3O7 - delta (MT-YBCO) superconductor can now trap multi-tesla fields, B sub t. The interaction of the trapped field and the critical current causes an outward pressure, proportional to B sub t (2), which can crack the magnet. The authors have done an experiment to observe such cracking in a mini-magnet fabricated from four MT-YBCO discs activated at 49 K using an applied field of 14 T. They have compared the results to existing theories which describe magnetic pressure in a trapped-field magnet (TFM) previously activated. They find that a modification is needed to describe magnetic pressure during the process of activation. They present the experimental results and the expanded theory, based on the simple Bean model. Theory and experiment show good agreement. The authors find that cracking is more likely during activation, and conclude that 10 T is achievable in TFM`s composed of present materials. Cracking is most probable at the center of a TFM, with the cracks running radially outward.

Analysis of effective resistance and eddy-current losses in multiturn winding of high-frequency magnetic components

Abstract: This paper develops a numerical model for calculation of eddy-current losses in a multiturn winding of a high-frequency transformer. The model assumes periodic arrangement of conductors, and uses the repeat elementary cell concept. The paper proposes analytical expressions and graphic dependences to determine effective frequency-dependent resistance of the winding. It computes the leakage field in the transformer window, taking into consideration the effective magnetic permeability of the multiturn winding as a heterogeneous medium. Finally, it analyzes the values of the resistance at various frequencies for two types of winding (solid conductor winding and Litz wire winding) by numerical and experimental methods.

Permanent Magnet Applications

Abstract: This chapter provides an overview of permanent magnet applications Permanent magnets are used in audio/video equipment, personal computers, and in printers Permanent magnets have several advantages over conventional (current-driven) electromagnets The fundamental advantage is that they can provide a relatively strong magnetic field over an extended spatial region for an indefinite period of time with no expenditure of energy The chapter discusses various permanent magnet applications It considers applications in which a magnet is used alone as a passive field source or in conjunction with other magnets as part of a functional device Specifically, it discusses bias magnet structures, high field structures, latching magnets, magnetic suspensions, and magnetic gears and couplings Further discusses various miscellaneous applications that utilize magnets including magnetic resonance imaging (MRI), magnetooptical recording, electrophotography and free-electron lasers