Showing papers on "Shell balance published in 2013"

Hydromagnetic Fluid Flow and Heat Transfer at a Stretching Sheet With Fluid-Particle Suspension and Variable Fluid Properties

Abstract: In this paper, we investigate the influence of temperature-dependent fluid properties on the flow and heat transfer characteristics of an electrically conducting dusty fluid over a stretching sheet. Temperature-dependent fluid properties are assumed to vary as a function of the temperature. The governing coupled nonlinear partial differential equations along with the appropriate boundary conditions are transformed into coupled, nonlinear ordinary differential equations by a similarity transformation. The resultant coupled highly nonlinear ordinary differential equations are solved numerically by a second order implicit finite difference scheme known as the Keller–Box method. The numerical solutions are compared with the approximate analytical solutions, obtained by a perturbation technique. The analysis reveals that even in the presence of variable fluid properties the transverse velocity of the fluid is to decrease with an increase in the fluid-particle interaction parameter. This observation holds even in the presence of magnetic field. Furthermore, the effects of the physical parameters on the fluid velocity, the velocity of the dust particle, the density of the dust particle, the fluid temperature, the dust-phase temperature, the skin friction, and the wall-temperature gradient are assessed through tables and graphs.

Model for fluid-solid interaction problem between a thin cylindrical shell and a transversal cross-flow

Abstract: For the fluid-solid interaction problem between an elastic thin cylindrical shell and a transversal cross-flow,United Lagrangian-Eulerian method is applied to build the model and theoretical equations,and the deformation and surface pressure coefficient of the shell of large bending are focused on.The results suggest that under the action of a transversal cross-flow,the round section of the shell is changed into approximate ellipse,besides,the deformation of the shell influences the surface pressure coefficient of the shell.By examples,the effects of parameters concerned on deformation and surface pressure coefficient of the shell are discussed.The research results can supply future reference when the interaction problems between a thin cylindrical shell and viscous fluid are being solved using United Lagrange-Euler method.

Approximate Solutions of Differential Equations of Non-Newtonian Fluids Flow Arising in the Study of Helical Screw Rheometer

Abstract: The thesis presents the theoretical analyses of extrusion process inside Helical Screw Rheometer (HSR).Efforts to obtain better insight into the process must be mainly theoretical rather than experimental. But the hope, of course, is that better insight than experimental so gained will provide practical benefits such as better control of the processing, optimize the processing process and improve the quality of production. The main objective of the study is to develop mathematical models in order to evaluate the velocity profiles, shear stresses and volume flow rates for isothermal flow of incompressible non-Newtonian fluids in HSR.The calculations of these values are of great importance during the production process.In this thesis, two types of geometries are considered. ² In first geometry the Cartesian co-ordinates system is used to study the flow of third-grade fluid, co-rotational Maxwell fluid, Eyring fluid, Eyring-Powell fluid and Oldroyd 8-constant fluid models in HSR.The geometry of the HSR is simplified by unwrapping or flattening the channel, lands and the outside rotating barrel.A shallow infinite channel is considered by assuming the width of the channel large as compared to the depth.We also assumed that the screw surface, the lower plate, is stationary and the barrel surface, the upper plate, is moving across the top of the channel with a velocity at an angle to the direction of the channel.The phenomena is same as, the barrel held stationary and the screw rotates. Solutions for velocity profiles, volume flow rates, average velocity, shear and normal stresses, shear stresses at barrel surface and shear forces exerted on the fluid are obtained using analytical techniques.Adomian decomposition method is used to obtain the solutions for third-grade fluid, Eyring-Powell fluid and Oldroyd 8-constant fluid and perturbation method for co-rotational Maxwell fluid, where exact solution is obtained for Eyring fluid model.The effects of the rheological parameters, pressure gradients and flight angle on the velocity distributions are investigated and discussed.The behavior of the shear stresses is also discussed with the help of graphs for different values of non-Newtonian parameters. ² For better analysis cylindrical co-ordinates system is taken in second geometry, assuming that the outer barrel of radius r2 is stationary and the screw of radius r1 rotates with angular velocity W.Here we have used third-grade fluid model with and without flight angle and co-rotational Maxwell fluid model with nonzero flight angle in HSR.The analytical expressions for the velocities, shear and normal stresses and the shear stresses exerted by the fluid on the screw, volume flow rates and average velocity are derived using analytical techniques and the outcomes have been presented with the help of graphs.The effects of the rheological parameters and pressure gradients on the velocity distribution are investigated