Motilal Nehru National Institute of Technology Allahabad

About: Motilal Nehru National Institute of Technology Allahabad is a education organization based out in Allahabad, Uttar Pradesh, India. It is known for research contribution in the topics: Computer science & Control theory. The organization has 2475 authors who have published 5067 publications receiving 61891 citations. The organization is also known as: NIT Allahabad & Motilal Nehru Regional Engineering College.

Unsteady Flow of a Nanofluid over a Sphere with Nonlinear Boussinesq Approximation

Abstract: A theoretical study is presented of transient mixed convection boundary layer flow of a nanofluid in the forward stagnation region of a heated sphere which is rotating with time dependent angular velocity. The effect of the non-linear Boussinesq approximation is taken into account. The nanofluid is treated as a two-component mixture i.e. nano-particles distributed homogenously in a base fluid (water or gas). The effects of the Brownian motion and thermophoresis are included for the nanofluid and constant wall temperature is imposed at the sphere surface. The first and second laws of thermodynamics are employed in order to study thermophysics as well as heat and mass transfer phenomena. By introducing appropriate similarity variables the governing equations are transformed into a system of dimensionless, nonlinear, coupled, ordinary differential equations which are solved numerically by applying the second-order accurate implicit finite difference Keller box method. The reliability and efficiency of the obtained numerical results are validated via comparison with the previously published results for special cases. The effects of various parameters on primary and secondary velocities, temperature, nanofluid volume fraction (concentration), primary and secondary shear stress functions, Nusselt number function (wall heat transfer rate) and Sherwood number function (wall nanoparticle mass transfer rate) are visualized. Furthermore the influence of non-linear temperature parameter, Brinkman parameter (ratio of Brinkman number to dimensionless temperature ratio), local Reynolds number and unsteadiness parameter on entropy generation number is computed. A strong elevation in entropy generation number is computed with both increasing Brinkman parameter and unsteadiness parameter. Primary and secondary surface shear stresses, Nusselt number and Sherwood number also increase with unsteadiness and rotation parameters. Primary shear stress is boosted with increasing mixed convection parameter and Brownian motion effect whereas secondary shear stress is depressed. Temperatures are suppressed with increasing nonlinear temperature parameter whereas nano-particle concentrations are elevated. Increasing thermophoresis parameter enhances both temperatures and nano-particle concentration values. The simulations find applications in rotating chemical engineering mixing systems and nano-coating transport phenomena.

Processing of curved profiles on Ni-rich nickel–titanium shape memory alloy by WEDM

Abstract: In wire electrical discharge machining (WEDM) process, to the machine, sharp corner without error is an extremely challenging issue which is vital for precision machining. Owing to the presence of ...

Entanglement dynamics in two-parameter qubit---qutrit states under Dzyaloshinskii---Moriya interaction

Abstract: We study entanglement dynamics in two-parameter qubit---qutrit states under the influence of Dzyaloshisnhkii---Moriya (DM) interaction. Our system consists of a qubit---qutrit pair as a closed system initially in two-parameter class of states, and one environmental qubit interacts with the qutrit of the closed system via DM interaction. We divide our analysis into two cases. In the first case, we study the entanglement dynamics in separable region, and in the second case we study the same in non-separable region. The DM interaction produces the entanglement in separable region with entanglement sudden death (ESD) and some states in this region remain unaffected by the same. In non-separable region, all the states are affected by DM interaction. The DM interaction excites the entanglement but does not produce ESD in this region. We observed that probability amplitude of environmental qubit does not affect the entanglement in two-parameter qubit---qutrit states in both the regions.

Kano integrated robust design approach for aesthetical product design: a case study of a car profile

Abstract: Visual shape parameters and aesthetic aspects of a product are one of the crucial factors for the success of a product in the market. The type and the value of the shape parameters plays an important role in visual appearance of a product and designers tends to be critical while deciding these parameters. The aesthetic aspect of a product has been matter of concern for researchers with its electromechanical design. The Kano model has been found to be a useful tool to establish the relationship between performance criteria and customer satisfaction. To achieve the desired customer satisfaction weight of each product criteria is determined by using Kano model. This study presents an integrative design approach combining the Kano model, Taguchi method and grey relation analysis to obtain the optimal combination of shape parameters and aesthetic aspects. Prioritized criteria of aesthetic attributes have been abstracted through proposed methodology. A case study has been presented to evolve a profile of a car.

Multiresponse Optimization of Electro-Discharge Diamond Face Grinding Process Using Robust Design of Experiments

Abstract: This article presents an investigation of the machining parameters design for electro-discharge diamond face grinding (EDDFG). The setup for EDDFG was developed, and experiments were conducted on tungsten carbide cobalt (WC-10wt%Co) composite workpiece. The input machining parameters used in the present study were wheel speed, current, pulse on time, and duty factor. The settings of machining parameters were determined by using Taguchi's robust design approach. The machining parameters were optimized with multiresponse characteristics of material removal rate (MRR), wheel wear rate (WWR), and average surface roughness (ASR). Multiresponse signal-to-noise (MSNR) ratio was applied to measure the performance characteristics deviating from the actual value. Analysis of variance (ANOVA) was employed to identify the level of importance of the machining parameters on the multiple performance characteristics considered. Finally, experimental confirmation was carried out to identify the effectiveness of this propo...