11 research outputs found
Investigation on Energy Distribution in Steady and Unsteady Flow Instabilities through a Bend Square Pipe
No full textIon-Slip Effects on Bingham Fluid Flowing Through an Oscillatory Porous Plate with Suction
No full textThis paper investigates the remarkable effects for introducing the Ion-slip characteristics in the magnetohydrodynamic phenomena on the drift of Bingham fluid when flowing through the inner territory of two porous parallel plates in correspondence with the suction case. The lower plate (L-plate) is as steady while the upper one (U-plate) is oscillatory, which oscillates in its own plane at time t>0. A magnetic field, which is uniform, is affixed perpendicular to the plates. The U-plate temperature oscillates while the L-plate temperature is constant. Numerical performance is presented by the MATLAB R2015a simulation tool with the explicit Finite difference Method (FDM) algorithm. To ensure the preciseness and convergence of the solutions, careful attention has been given on the criteria of stability and convergence of the FDM schemes. As an outcome, the converged solution is obtained for Pr ≥ 0.066, βi ≥ 2, Ha ≤ 20, h ≤ 8, S ≥ −10 and Re ≤ −0.017 with the arbitrary choice of βe = 0.10 and Ec = 0.01. The mesh sensibility test gives the competent mesh space at (m,n)=(60,60). The time sensibility test ensures that the solutions at dimensionless time, τ=2.0 will be steady-state. The exactitude of the current study is obtained by comparing with the published results. Finally, the physical influences of several governing parameters, including Ionslip on the fluid property like velocity, local shear stress, temperature and Nusselt number are discussed and decorated graphically
Analytical Investigation on the Underexpanded Jet Issuing from Circular and Elliptic Nozzles
No full textThe supersonic jet issuing from circular and elliptic exit of convergent-divergent nozzle has been investigated by rainbow schlieren deflectometry and modified linearized model. In experimentally, a design Mach number of 1.5 followed by a cylindrical duct with an inner diameter of 10 mm, and length of 50 mm are considered to measure the density, internal flow features of jet combing with the computed tomography. In theoretically, a modified vortex sheet model taking viscosity into account has been proposed. The properties of Bessel’s and Mathieu functions with the first Fourier mode of eigenvalues are executed for the individual exit geometry to evaluate the explicit solution of inviscid and viscous jet separately. The embodied results of density, shock-cell spacing, and size measuring have also been examined theoretically. In comparison, the accomplished yields are shown better agreement with published data due to the aspect ratios, nozzle pressure ratios and design Mach number arbitrarily
Analytical Investigation on the Underexpanded Jet Issuing from Circular and Elliptic Nozzles
No full text北九州市立大学博士(工学)The supersonic jet issuing from circular and elliptic exit of convergent-divergent nozzle has been investigated by rainbow schlieren deflectometry and modified linearized model. In experimentally, a design Mach number of 1.5 followed by a cylindrical duct with an inner diameter of 10 mm, and length of 50 mm are considered to measure the density, internal flow features of jet combing with the computed tomography. In theoretically, a modified vortex sheet model taking viscosity into account has been proposed. The properties of Bessel’s and Mathieu functions with the first Fourier mode of eigenvalues are executed for the individual exit geometry to evaluate the explicit solution of inviscid and viscous jet separately. The embodied results of density, shock-cell spacing, and size measuring have also been examined theoretically. In comparison, the accomplished yields are shown better agreement with published data due to the aspect ratios, nozzle pressure ratios and design Mach number arbitrarily.doctoral thesi
Unsteady Viscous Incompressible Bingham Fluid Flow through a Parallel Plate
No full textNumerical investigation for unsteady, viscous, incompressible Bingham fluid flow through parallel plates is studied. The upper plate drifts with a constant uniform velocity and the lower plate is stationary. Both plates are studied at different fixed temperatures. To obtain the dimensionless equations, the governing equations for this study have been transformed by usual transformations. The obtained dimensionless equations are solved numerically using the explicit finite difference method (FDM). The studio developer Fortran (SDF) 6.6a and MATLAB R2015a are both used for numerical simulations. The stability criteria have been established and the system is converged for Prandtl number P r ≥ 0.08 with Δ Y = 0.05 and Δ τ = 0.0001 as constants. As a key outcome, the steady-state solutions have been occurred for the dimensionless time τ = 4.00 The influence of parameters on the flow phenomena and on shear stress, including Nusselt number, are explained graphically. Finally, qualitative and quantitative comparison are shown
Fluid flow along the Riga plate with the influence of magnetic force in a rotating system
No full textEMHD radiating fluid flow along a vertical Riga plate with suction in a rotating system
No full textThis study is performed on the numerical investigation of electro-magnetohydrodynamic (EMHD) radiating fluid flow nature along an infinitely long vertical Riga plate with suction in a rotating system. The prevailing equations are generated from the Navier–Stokes’ and energy equations. A uniform suction velocity is introduced to control the flow. The prevailing boundary layer (BL) equations are the stuff to delineate the mechanical features of the flowing nature along with the electromagnetic device (Riga plate). Accordingly, the use of usual transformations on the equations transformed those into a coupled dimensionless system of non-linear partial differential equations (PDEs). After conversion, the elucidation of the set of equations is conducted numerically by an explicit finite difference method (FDM). The criteria for stable and converging solutions are constructed to find restrictions on various non-dimensional parameters. The retrieved restrictions are Pr≥0.19,Rd≥0.1,S≥ 1 , Ec=0.01 and 0 < R≤ 0.1. Furthermore, sensitivity tests on mesh and time as well as comparison within the literature have been demonstrated in graphical and tabular form. Finally, the important findings of the non-dimensional parameters influences have been portrayed in graphical manner by using the MATLAB R2015a tool. A substantial uprise is noted for both the velocities (secondary and primary) under the rising actions of the modified Hartmann number, whereas the suction parameter suppresses both the velocities.</p
Bifurcation structure and unsteady solutions through a curved square duct with bottom wall heating and cooling from the ceiling
No full text
Non-isothermal Bingham fluid flow between two horizontal parallel plates with Ion-slip and Hall currents
No full textThis study presents the numerical solution of velocity and temperature fields based on mass conservation, momentum and energy balances for the time-dependent Couette-Poiseuille flow of Bingham materials through channels. The channel flow of Bingham fluid concerns the flow of cement paste in the building industry and the mudflow in the drilling industry. The specific aim is to introduce the magnetohydrodynamic (MHD) phenomena specified by both Ion-slip and Hall currents into the non-isothermal channel flow in a theoretical approach. The Bingham constitutive equation is formulated by the generalized Newtonian fluid technique and solved by employing the explicit Finite Difference Method (FDM) using the MATLAB R2015a and Compaq Visual FORTRAN 6.6a both. For the exactness of numerical performance estimations, the criteria for stabilization and the convergence factor are analyzed. The velocity and temperature profiles are discussed individually at the moving and stationary walls of the channel. It is observed that magnetohydrodynamic phenomena accelerate the flow, and the temperature distributions reach the steady-state situation earlier than velocity distributions. Furthermore, the dominance of MHD parameters on the velocity distributions, shear stress, temperature distributions, and Nusselt number are discussed.</p
