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Mixed convection in a lid-driven square enclosure with a rotating cylinder inside has been analyzed using non-Newtonian ferrofluid (Fe3O4-water). Left vertical wall is heated while the right vertical wall is kept cold. Bottom wall and cylinder surface are assumed to be adiabatic. Top wall has a moving lid with a constant velocity U0. Galerkin method of finite element analysis has been used to solve the governing equations. Numerical accuracy of solution is ensured by the grid independency test. A variety of Richardson number (Ri = 0.1 - 10) at a governing Reynolds number (Re = 100), power law index (n = 0.5 - 1.5), rotational speed (Ω = 0 - 15) and solid volume fraction of ferrous particles (φ = 0 - 0.05) are employed for this present problem. To illustrate flow and thermal field, streamline and isotherms are included. Average Nusselt number plots are shown to show overall heat transfer rate. It is observed that better heat transfer is achieved at higher rotational speed (Ω), Richardson number (Ri) and po...

Tungsten is a promising material and has potential use as battery anode. Tungsten nanowires are gaining attention from researchers all over the world for this wide field of application. In this paper, we investigated effect of temperature and geometric parameters (diameter and aspect ratio) on elastic properties of Tungsten nanowire. Aspect ratios (length to diameter ratio) considered are 8:1, 10:1, and 12:1 while diameter of the nanowire is varied from 1-4 nm. For 2 nm diameter sample (aspect ratio 10:1), temperature is varied (10K ~ 1500K) to observe elastic behavior of Tungsten nanowire under uniaxial tensile loading. EAM potential is used for molecular dynamic simulation. We applied constant strain rate of 109 s−1 to deform the nanowire. Elastic behavior is expressed through stress vs. strain plot. We also investigated the fracture mechanism of tungsten nanowire and radial distribution function. Investigation suggests peculiar behavior of Tungsten nanowire in nano-scale with double peaks in stress vs....

A lot of water resources which have some potential to meet the local power demand are wasted in Bangladesh. This paper encompasses a new concept to use the road side canal water flow potential and convert it in small scale (micro or mini) scale power generation which can meet the local power demand of Bangladesh. A numerical investigation has been done on the water flow rate and head of the canal water and in the light of this data total power is calculated. Power cost relation along with environmental feasibility also been showed to evident that this is a promising future technology for meet the power crisis in Bangladesh.

Stanene, a graphene like two dimensional honeycomb structure of tin has attractive features in electronics application. In this study, we performed molecular dynamics simulations using modified embedded atom method potential to investigate mechanical properties of stanene. We studied the effect of temperature and strain rate on mechanical properties of α-stanene for both uniaxial and biaxial loading conditions. Our study suggests that with the increasing temperature, both the fracture strength and strain of the stanene decrease. Uniaxial loading in zigzag direction shows higher fracture strength and strain compared to the armchair direction, while no noticeable variation in the mechanical properties is observed for biaxial loading. We also found at a higher loading rate, material exhibits higher fracture strength and strain. These results will aid further investigation of stanene as a potential nano-electronics substitute.

A numerical investigation has been carried out in this paper to study the effect of varying Lewis number on the nature of heat and mass transfer in a triangular solar collector at unsteady condition. The triangular solar collector consists of two inclined glass covers and an absorber plate. The situation studied here resembles heat transfer phenomena in solar collectors and hence a thorough study on the effect of different parameters dictating this kind of heat transfer is essential. Bottom corrugated wall is subjected to high temperature and high concentration. Finite element method was employed to solve the unsteady dimensionless governing equations of continuity, momentum, energy and concentration of the problem. Calculations were carried out for Raleigh number ranging from 104 to 106 and for dimensionless time parameter = 0.1, 0.5 and 1. For the conditions mentioned here the effect of varying local and overall Nusselt and Sherwood number at those conditions are discussed. A comprehensive explanation follows each result.