Anastasia Bushueva, Olga Vlasova, Denis Polezhaev^*

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.4, pp. 847-857, 2024, DOI:10.32604/fdmp.2024.048271

Abstract The steady flow in a Hele-Shaw cell filled with fluids with a high viscosity contrast in the presence of fluid oscillations is experimentally studied. The control of oscillatory dynamics of multiphase systems with interfaces is a challenging technological problem. We consider miscible (water and glycerol) and immiscible (water and high-viscosity silicone oil PMS-1000) fluids under subsonic oscillations perpendicular to the interface. Observations show that the interface shape depends on the amplitude and frequency of oscillations. The interface is undisturbed only in the absence of oscillations. Under small amplitudes, the interface between water and glycerol widens due to mixing. When the… More >

Matthew R. Coburn¹, Charlie Young², Chris Smith², Graham Schultz², Miguel Robayo³, Zheng-Tong Xie^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.3, pp. 547-562, 2024, DOI:10.32604/fdmp.2023.028601

Abstract A prototype cleanroom for hazardous testing and handling of satellites prior to launcher encapsulation, satisfying the ISO8 standard has been designed and analyzed in terms of performances. Unsteady Reynolds Averaged Navier-Stokes (URANS) models have been used to study the related flow field and particulate matter (PM) dispersion. The outcomes of the URANS models have been validated through comparison with equivalent large-eddy simulations. Special attention has been paid to the location and shape of the air intakes and their orientation in space, in order to balance the PM convection and diffusion inside the cleanroom. Forming a cyclone-type flow pattern inside the… More >

Tapas Ray Mahapatra^a, Sumanta Sidui^b, Samir Kumar Nandy^c,*

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-15, 2014, DOI:10.5098/hmt.5.15

Abstract The effect of variable transverse magnetic field on steady two-dimensional indirect natural convection flow of an incompressible viscous fluid over a horizontal hot flat plate is theoretically studied. The governing partial differential equations are transformed into ordinary ones by similarity transformation and solved numerically using fourth order Runge-Kutta method with shooting technique. The results are obtained for the skin friction coefficient and the local Nusselt number as well as the dimensionless velocities, temperature for some values of the magnetic parameter (M) subject to either prescribed (constant or variable) surface temperature or prescribed (variable) heat flux. It is seen that the… More >

Junying Wei^*, Gang Li, Chenrui Zhang, Wenwen Chang, Jidai Wang

Frontiers in Heat and Mass Transfer, Vol.21, pp. 199-214, 2023, DOI:10.32604/fhmt.2023.041793

Abstract To study the complex internal flow field variation and output characteristics of a variable base radius scroll expander, this paper uses dynamic mesh techniques and computational fluid dynamics (CFD) methods to perform transient numerical simulations of a variable base radius scroll expander. Analysis of the flow field in the working cavity of a variable base radius scroll expander at different spindle angles and the effect of different profiles, speeds and pressures on the output characteristics of the scroll expander. The results of the study show that due to the periodic blocking of the inlet by the orbiting scroll, the fluid… More >

D. Lourdu Immaculate^a , R. Muthuraj^b,*, Anant Kant Shukla^c, S. Srinivas^d

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-14, 2016, DOI:10.5098/hmt.7.12

Abstract This article aims to examine the MHD unsteady flow of Williamson nanofluid in a vertical channel filled with a porous material and oscillating wall temperature. The modeling of this problem is transformed to ordinary differential equations by collecting the non-periodic and periodic terms and then series solutions are obtained by using a powerful method known as the homotopy analysis method (HAM). The influence of involved parameters on heat and mass transfer characteristics of the fluid flow is computed and presented graphically. Further, variations on volume flow rate, coefficient of skin friction, heat transfer rate and mass transfer rate are also… More >

Odelu Ojjela^*, K. Pravin Kashyap, N. Naresh Kuma, Samir Kumar Das

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-9, 2016, DOI:10.5098/hmt.7.32

Abstract This article presents an unsteady incompressible Upper Convected Maxwell (UCM) fluid flow with temperature dependent thermal conductivity between parallel porous plates which are maintained at different temperatures varying periodically with time. Assume that there is a periodic suction and injection at the upper and lower plates respectively. The governing partial differential equations are reduced to non linear ordinary differential equations by using similarity transformations and the solution is obtained using differential transform method. The effects of various fluid and geometric parameters on the velocity components, temperature distribution and skin friction are discussed in detail through graphs. More >

CH. Amanulla^a,b , N. Nagendra^a,1 , M. Surya Narayana Reddy^b , A. Subba Rao^a , O. Anwar Bég^c

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-13, 2017, DOI:10.5098/hmt.8.29

Abstract In this article, the heat, momentum and mass (species) transfer in external boundary layer flow of Casson nanofluid from an isothermal sphere surface is studied theoretically. The effects of Brownian motion and thermophoresis are incorporated in the model in the presence of both heat and nanoparticle mass transfer. The governing partial differential equations (PDEs) are transformed into highly nonlinear, coupled, multi-degree non-similar partial differential equations consisting of the momentum, energy and concentration equations via appropriate non-similarity transformations. These transformed conservation equations are solved subject to appropriate boundary conditions with a second order accurate finite difference method of the implicit type.… More >

N. Vijaya^a,*, Y. Hari Krishna^a , K. Kalyani^b, G.V.R. Reddy^a

Frontiers in Heat and Mass Transfer, Vol.11, pp. 1-11, 2018, DOI:10.5098/hmt.11.19

Abstract The present paper deals with the thermo physical properties of a Casson fluid through an oscillating vertical wall embedded through porous medium under the influence transverse magnetic field, radiation, constant heat source and first order chemical reaction. The radiative heat loss is modelled by using Rosseland approximation. Similarity variables were used to convert the partial differential equations into ordinary differential equation. The transformed ordinary differential equations are solved numerically using Runge - Kutta -Fehlberg method with shooting technique. In order to get perfect perception of the flow pattern we obtain the graphs of axial velocity, temperature and concentrations profiles for… More >

Elyazid Flilihi, Mohammed Sriti, Driss Achemlal

Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-10, 2019, DOI:10.5098/hmt.12.12

Abstract A numerical investigation is performed to analyze the transient laminar free convection over an isothermal inclined plate embedded in a saturated porous medium with the viscous dissipation effects. The flow in the porous medium is modeled with the Darcy-Brinkman- Forchheimer model, taking into account the convective term. The dimensionless nonlinear partial differential equations are solved numerically using an explicit finite difference method. The effects of different parameters: (1 ≤ Re ≤ 10 ; 10⁻² ≤ Da ≤ 10 ; 0 ≤ Gr ≤ 50 ; 0 ≤ F r ≤ 3 ; 0 ≤ Ec ≤ 1 ; 0 ≤… More >

Yan-Juan Zhao^a,*, Yu-Liang Zhang^b,† , Chen-Liang Zhang^b

Frontiers in Heat and Mass Transfer, Vol.17, pp. 1-7, 2021, DOI:10.5098/hmt.17.3

Abstract Vortex flowmeter adopts advanced micro processing technology, which has the advantages of strong function, wide flow range, simple operation and maintenance, convenient installation and use. It is widely used in petroleum, chemical industry, electric power, metallurgy, urban gas supply and other industries to measure various gas flows. In order to study the characteristics of the inner flow passage of the vortex flowmeter and reach the normal working standard of the vortex flowmeter, this paper uses CFX to calculate the turbulent kinetic energy, eddy viscosity and flow velocity of the inner flow passage of the vortex flowmeter and analyze their distribution,… More >