Open Access

ARTICLE

Sayavur I. Bakhtiyarov¹, Dennis A. Siginer²
FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.1, pp. 1-22, 2009, DOI:10.3970/fdmp.2009.005.001
Abstract Strong inhomogeneous magnetic fields are necessary to generate a finite levitation force in ground based electromagnetic levitation techniques. External forces such as magnetic and gravitational forces influence the oscillation spectrum and counteract the surface movement resulting in a frequency shift, and making the use of electromagnetic levitation techniques in microgravity an attractive alternative to measure thermophysical properties of liquid metals. Under microgravity conditions the magnetic field strength around a liquid droplet is significantly lower than that required to position the same specimen against earth gravity. Hence, a low magnetic field strength results in a low More >

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1571

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ARTICLE

M. El Alami¹, E. A. Semma^2,3, M. Najam¹, R. Boutarfa²
FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.1, pp. 23-36, 2009, DOI:10.3970/fdmp.2009.005.023
Abstract This study is devoted to the investigation of natural convection in a two dimensional horizontal channel with rectangular heated blocks at the bottom. The aspect ratio of the channel is A = L'/H' = 5. The blocks are heated with a constant temperature while the upper plane of the channel is cold. The governing equations are solved using a finite volumes method and the SIMPLEC algorithm is used for the treatment of the pressure-velocity coupling. Special emphasis is given to detail the effect of the Rayleigh number and blocks height on the heat transfer and the More >

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1334

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ARTICLE

Edoardo Bucchignani¹
FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.1, pp. 37-60, 2009, DOI:10.3970/fdmp.2009.005.037
Abstract This article describes an implicit method for the solution of time dependent Navier-Stokes equations written in terms of vorticity and velocity. The field equations are discretized using a finite volume technique over quadrilateral meshes.
The numerical code has been applied to the classical window cavity test, employing a fine stretched non-uniform grid, in order to provide an accurate steady solution for a high value of the Rayleigh number (10⁸). It has also been performed a simulation for a value of Rayleigh larger than the critical value, in order to show the capabilities of the proposed More >

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1542

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1290

Open Access

ARTICLE

Lassig, J.¹, Montes, G., Quiroga, J.
FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.1, pp. 61-80, 2009, DOI:10.3970/fdmp.2009.005.061
Abstract This paper presents a description of the design and ensuing development of an automated liquid droplet generator and related utilization aboard the space shuttle, a) as a fluid positioning system for materials processing (attached droplet method), and b) as a means to measure surface oscillation of droplets under microgravity for determining their surface tension. More >

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1156

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ARTICLE

Davood Kalantari¹
FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.1, pp. 81-92, 2009, DOI:10.3970/fdmp.2009.005.081
Abstract In this paper a theoretical approach is elaborated for modelling the impact and ensuing spreading behaviour of a liquid droplet after its collision with a flat and rigid surface. The major outcomes of such a study can be summarized as follows: 1) The propagating-shock-wave velocity associated with the droplet is not a constant value but depends on the impact velocity and the physical and geometrical properties of the droplet. 2) The initial radial ejection velocity of the lamella is proportional to the shock-wave velocity (ua) and the impact velocity (0) according to the expression (a-u0)1/2. More >

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1593

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1090

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ARTICLE

K.V. Pagalthivarthi¹, P.K. Gupta²
FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.1, pp. 93-122, 2009, DOI:10.3970/fdmp.2009.005.093
Abstract The objective of the present work is to predict erosive wear in multisize dense slurry flow in a rotating channel. The methodology comprises numerical prediction of two-phase flow which is accomplished using the Galerkin finite element method. The wear models for both sliding wear and impact wear mechanisms account for the particle size dependence. The effect of various operating parameters such as rotation rate, solids concentration, flow rate, particle size distribution and so forth has been studied. Results indicate that wear rate in general increases along the pressure-side of the channel with rotation rate, overall More >

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