Open Access
ARTICLE
J.R. Lin1, L.M. Chu2, T.L. Chou3, L.J. Liang3, P.Y. Wang3
FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.2, pp. 163-177, 2014, DOI:10.3970/fdmp.2014.010.163
Abstract We investigate the influence of non-Newtonian micropolar fluids on the dynamic characteristics of wide tapered-land slider bearings. The study is carried out on the basis of the micro-continuum theory originally developed by Eringen (1966). Analytical expressions for the linear dynamic coefficients are provided and compared with earlier results in the literature. In particular, direct comparison with the Newtonian fluid-lubricated tapered-land bearings by Lin et al. (2006) indicates that the use of non-Newtonian micropolar fluids can lead to a significant increase in the values of stiffness and damping coefficients. Such improvements are found to be even more pronounced for larger values… More >
Open Access
ARTICLE
Paras Ram1,2, Vikas Kumar3
FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.2, pp. 179-196, 2014, DOI:10.3970/fdmp.2014.010.179
Abstract The present study is carried out to examine the effects of temperature dependent variable viscosity on the three dimensional steady axi-symmetric Ferrohydrodynamic (FHD) boundary layer flow of an incompressible electrically nonconducting magnetic fluid in the presence of a rotating disk. The disk is subjected to an externally applied magnetic field and is maintained at a uniform temperature. The nonlinear coupled partial differential equations governing the boundary layer flow are non dimensionalized using similarity transformations and are reduced to a system of coupled ordinary differential equations. To study the effects of temperature dependent viscosity on velocity profiles and temperature distribution within… More >
Open Access
ARTICLE
V. Shevtsova1, Y. Gaponenko1, H.C. Kuhlmann2, M. Lappa3, M. Lukasser2, S. Matsumoto4, A. Mialdun1, J.M. Montanero5, K. Nishino6, I. Ueno7
FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.2, pp. 197-240, 2014, DOI:10.3970/fdmp.2014.010.197
Abstract Pure surface-tension-driven flow is a unique type of flow that can be controlled through external manipulation of thermal and/or mechanical boundary conditions at the free liquid surface where the entire driving force for the convection is generated. This unique feature has been exploited in recent studies for the active control of the flow instability. The use of forced coaxial gas streams has been proposed as a way to stabilize the Marangoni convection in liquid bridges in the planned space experiment JEREMI (Japanese and European Research Experiment on Marangoni Instabilities). It is aimed at understanding the mechanism of the instability and… More >
Open Access
ARTICLE
D. Benmouhoub1, A. Mataoui1
FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.2, pp. 241-260, 2014, DOI:10.3970/fdmp.2014.010.241
Abstract The present work is devoted to the numerical study of the interaction of an inclined plane turbulent jet with a moving horizontal isothermal hot wall. The inclination of the jet allows the control of the stagnation point location. Numerical predictions based on statistical modeling are obtained using a second order Reynolds stress turbulence model coupled to an enhanced wall treatment. For a given impinging distance H (H =8e), the considered problem parameters are: (a) jet exit Reynolds number (Re, based on the thickness "e" of the nozzle) in the range from 10000 to 25000, (b) surface-to-jet velocity ratio Rsj from… More >
Open Access
ARTICLE
M. Si Abdallah1, B. Zeghmati2
FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.2, pp. 261-277, 2014, DOI:10.3970/fdmp.2014.010.261
Abstract In the present work, a numerical analysis is performed of the combined effects of (opposing) thermal and solutal buoyancy in the presence of a wavy (vertical) surface. The boundary layer equations and related boundary conditions are discretized using a finite volume scheme and solved numerically using a Gauss-Seidel algorithm. The influence of the wavy geometry (in terms of related wavelength L and amplitude a) and the buoyancy ratio N on the local Nusselt and Sherwood numbers and on the skin-friction coefficient are studied in detail. Results show that when Pr < Sc, negative values of the buoyancy parameter, N tend… More >
Open Access
ARTICLE
Mustapha Faraji1, El Alami Mustapha, Najam Mostafa
FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.2, pp. 279-298, 2014, DOI:10.3970/fdmp.2014.010.279
Abstract A study is reported of heat transfer and melting in a fan-less thermal management system consisting of an insulated horizontal cavity filled with a phase change material (PCM) and heated from below by a conducting plate supporting three identical protruding heat sources. Such a PCM enclosure can be used as a heat sink for the cooling of electronic components. The advantage of this cooling strategy is that PCMs characterized by high energy storage density and small transition temperature interval, are able to store a high amount of heat (thereby providing efficient passive cooling). A two-dimensional simulation model is developed that… More >