Numerical Study on Compressibility Effect on Dynamics of Two-dimensional Vortex Pair

The two-dimensional(2D) materials are highly promising candidates to realise elegant and e cient transistor. In the present letter, we conjecture a novel co-planar metal-insulator-semiconductor(MIS) device(capacitor) completely based on lateral 2D materials architecture and perform numerical study of the capacitor with a particular emphasis on its di erences with the conventional 3D MIS electrostatics. The space-charge density features a long charge-tail extending into the bulk of the semiconductor as opposed to the rapid decay in 3D capacitor. Equivalently, total space-charge and semiconductor capacitance densities are atleast an order of magnitude more in 2D semiconductor. In contrast to the bulk capacitor, expansion of maximum depletion width in 2D semiconductor is observed with increasing doping concentration due to lower electrostatic screening. The heuristic approach of performance analysis(2D vs 3D) for digital-logic transistor suggest higher ON-OFF current ratio in the long-channel limit even without third dimension and considerable room to maximise the performance of short-channel transistor. The present results could potentially trigger the exploration of new family of co-planar at transistors that could play a signi significant role in the future low-power and/or high performance electronics.<br>

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Numerical Study of Two-Dimensional Burger’s Equation: The Phenomenon of the Fall of Sediment Particles Using Incremental Differential Quadrature Method

Iranian Journal of Science and Technology Transactions of Civil Engineering ◽

10.1007/s40996-021-00657-0 ◽

2021 ◽

Author(s):

Mohammad Vaghefi ◽

Hossein Rahideh ◽

Sam Boveiri ◽

Iman Rezaei

Keyword(s):

Numerical Study ◽

Differential Quadrature Method ◽

Differential Quadrature ◽

Two Dimensional ◽

Quadrature Method ◽

Burger's Equation ◽

Burger’S Equation ◽

Sediment Particles

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Specific heat of ordered and isotopically disordered lattices

Canadian Journal of Physics ◽

10.1139/p78-182 ◽

1978 ◽

Vol 56 (10) ◽

pp. 1390-1394

Author(s):

K. P. Srivastava

Keyword(s):

Specific Heat ◽

Low Temperatures ◽

Numerical Study ◽

Three Dimensional ◽

Constant Volume ◽

Nearest Neighbour ◽

Two Dimensional ◽

Appreciable Difference ◽

Substantial Change ◽

Neighbour Interaction

An extensive numerical study on specific heat at constant volume (Cv) for ordered and isotopically disordered lattices has been made. Cv at various temperatures for ordered and disordered linear and two-dimensional lattices have been compared and no appreciable difference in Cv between these two structures has been observed. Effect of concentration of light atoms on Cv for three-dimensional isotopically disordered lattices has also been shown.In spite of taking next-nearest-neighbour interaction into account, no substantial change in Cv between the ordered and isotopically disordered linear lattices has been found. It is shown that the low lying modes contribute substantially at low temperatures.

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Numerical study of two-dimensional wet foam over a range of shear rates

Physical Review Fluids ◽

10.1103/physrevfluids.2.093303 ◽

2017 ◽

Vol 2 (9) ◽

Cited By ~ 1

Author(s):

T. Kähärä

Keyword(s):

Numerical Study ◽

Two Dimensional ◽

Shear Rates

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A numerical study of the descent of a vortex pair in a stably stratified atmosphere

Journal of Fluid Mechanics ◽

10.1017/s0022112075002406 ◽

1975 ◽

Vol 71 (1) ◽

pp. 1-13 ◽

Cited By ~ 30

Author(s):

F. M. Hill

Keyword(s):

Numerical Methods ◽

Numerical Study ◽

Vortex Pair ◽

Vortex Sheet ◽

Discrete Line

Numerical methods are used to investigate the motion of a horizontal vortex pair through a stably stratified atmosphere. The vortices carry with them a mass of fluid whose density differs from that of the air through which it descends, and the surface of this accompanying fluid becomes a vortex sheet, which is modelled by a set of discrete line vortices.It is shown that, at first, the vortex pair slows down with the shape of the envelope of the accompanying fluid remaining constant. Later, vorticity concentrates at the rear, initiating detrainment and causing a downward acceleration of the vortex pair. Throughout the motion, the vortices approach each other.

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A Numerical Study of Unsteady Natural Convection in a Rectangular Enclosure: The Effect of Compressibility

Heat Transfer, Volume 2 ◽

10.1115/imece2004-60294 ◽

2004 ◽

Author(s):

K. M. Akyuzlu ◽

Y. Pavri ◽

A. Antoniou

Keyword(s):

Mathematical Model ◽

Stokes Equations ◽

Numerical Study ◽

Vertical Wall ◽

Ideal Gas ◽

Working Fluid ◽

Two Dimensional ◽

Algebraic Equations ◽

Rectangular Enclosure ◽

Circulation Patterns

A two-dimensional, mathematical model is adopted to investigate the development of buoyancy driven circulation patterns and temperature contours inside a rectangular enclosure filled with a compressible fluid (Pr=1.0). One of the vertical walls of the enclosure is kept at a higher temperature then the opposing vertical wall. The top and the bottom of the enclosure are assumed insulated. The physics based mathematical model for this problem consists of conservation of mass, momentum (two-dimensional Navier-Stokes equations) and energy equations for the enclosed fluid subjected to appropriate boundary conditions. The working fluid is assumed to be compressible through a simple ideal gas relation. The governing equations are discretized using second order accurate central differencing for spatial derivatives and first order forward finite differencing for time derivatives where the computation domain is represented by a uniform orthogonal mesh. The resulting nonlinear equations are then linearized using Newton’s linearization method. The set of algebraic equations that result from this process are then put into a matrix form and solved using a Coupled Modified Strongly Implicit Procedure (CMSIP) for the unknowns (primitive variables) of the problem. A numerical experiment is carried out for a benchmark case (driven cavity flow) to verify the accuracy of the proposed solution procedure. Numerical experiments are then carried out using the proposed compressible flow model to simulate the development of the buoyancy driven circulation patterns for Rayleigh numbers between 103 and 105. Finally, an attempt is made to determine the effect of compressibility of the working fluid by comparing the results of the proposed model to that of models that use incompressible flow assumptions together with Boussinesq approximation.

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