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 More >

Paras Ram^1,2, 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 More >

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 >

K. Lahmer¹, R. Bessaïh¹, A. Scipioni², M. El Ganaoui²

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.1, pp. 149-162, 2014, DOI:10.3970/fdmp.2014.010.149

Abstract This paper summarizes the outcomes of a numerical study about the phenomenon of hydrogen absorption in an axisymmetric tank geometry containing magnesium hydride heated to 300˚C and at moderate storage pressure 1 MPa. The governing equations are solved with a fully implicit finite volume numerical scheme (as implemented in the commercial software FLUENT). Different kinetic reaction equations modeling hydrogen absorption are considered and the related numerical simulations are compared with experimental results. Spatial and temporal profiles of temperature and concentration in hydride bed are plotted. More >

A. Abbassi^1,2, H. Ben Aissia¹

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.1, pp. 115-147, 2014, DOI:10.3970/fdmp.2014.010.115

Abstract This paper describes the transition from forced to mixed convection in a jet flow with variable properties. The classical laminar layer analysis is extended by taking into account the dependence of physical properties on temperature. The related model relies on the assumption that the variations of Prandtl number and specific heat at constant pressure are sufficiently small to be neglected. A second-order finite-difference numerical method based on a staggered grid is used to analyze transition, hydrodynamic and heat transfer phenomena in the jet. The dimensionless control parameter, Λ = T₀/T_∞, is limited to values less than More >

Imen Mejri^1,2, Ahmed Mahmoudi¹, Mohamed Ammar Abbassi¹, Ahmed Omri¹

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.1, pp. 83-114, 2014, DOI:10.3970/fdmp.2014.010.083

Abstract This study examines natural convection in a square enclosure filled with a water-Al₂O₃ nanofluid and subjected to a magnetic field. The side walls of the cavity have spatially varying sinusoidal temperature distributions. The horizontal walls are adiabatic. A Lattice Boltzmann method (LBM) is applied to solve the governing equations for fluid velocity and temperature. The following parameters and related ranges are considered: Rayleigh number of the base fluid, from Ra=10³ to 10⁶, Hartmann number from Ha=0 to 90, phase deviation (γ =0, π/4, π/2, 3π/4 and π) and solid volume fraction of the nanoparticles between ø = 0 and More >

Yan Shen¹, Hong Zhang^1,2,3, Hui Xu¹, Tong Bai¹, Ping Yu¹

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.1, pp. 63-81, 2014, DOI:10.3970/fdmp.2014.010.063

Abstract Single-unit and multi-unit models of porous media (metal felts) have been used to investigate thermal fluid-structure interaction phenomena in a liquid sodium system. Micro-scale aspects have been studied via numerical simulations. The permeability of metal felts has been measured experimentally to verify the reliability of the models used. This integrated approach has allowed a proper evaluation of the interdependencies among phenomena on different scales (including relevant information on skeleton deformation and pressure drop as a function of different parameters). Pressure drop generally increases with velocity and heat flux for both laminar and turbulent flows. The More >

Davood Kalantari¹, Cameron Tropea²

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.1, pp. 37-61, 2014, DOI:10.3970/fdmp.2014.010.037

Abstract This study presents a combined experimental and theoretical investigation on the formation and spreading of a liquid film on a flat and rigid wall due to spray impact. A dual-mode phase Doppler instrument is used to characterise the spray while the average film thickness is measured using a high-speed CCD camera. The experimental results are complemented with theoretical expressions derived under the assumption that the spray is stationary. A new model for the prediction of the average wall film thickness is formulated taking into account the mean Reynolds number of the impacting drops, the flux More >

H. C. Kuhlmann¹, M. Lappa², D. Melnikov³, R. Mukin¹,F. H. Muldoon¹, D. Pushkin⁴, V. Shevtsova², I. Ueno⁵

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.1, pp. 1-10, 2014, DOI:10.3970/fdmp.2014.010.001

Abstract The rapid accumulation of particles suspended in a thermocapillary liquid bridge is planned to be investigated during the JEREMI experiment on the International Space Station scheduled for 2016. An overview is given of the current status of experimental and numerical investigations of this phenomenon. More >

A. Ramach,ra Murthy^1,2, V. Ramesh Kumar¹, Smitha Gopinath¹, PrabhatRanjan Prem¹, Nagesh R. Iyer³, Reshmi Balakrishnan⁴

CMC-Computers, Materials & Continua, Vol.44, No.1, pp. 59-72, 2014, DOI:10.3970/cmc.2014.044.059

Abstract This paper investigates the flexural performance of a sandwich panel made up of ultra high strength concrete (UHSC) as top and bottom skin and cold formed steel as sandwich. A novel sandwich panel has been designed such a way that bottom skin of UHSC is of precast in nature and top skin of UHSC is cast-insitu and cold formed steel (profiled sheet) as sandwich. The connection between top skin of UHSC and cold formed steel is made with self tapping screws. Flexural performance of UHSC sandwich panel has been tested under flexural loading and it… More >