By means of He's homotopy perturbation method (HPM) an approximate solution of velocity eld is derived for the ow in straight pipes of non-Newtonian uid obeying the Sisko model. The nonlinear equations governing the ow in pipe are for- mulated and analyzed, using homotopy perturbation method due to He. Furthermore, the obtained solutions for velocity eld is graphically sketched...

by means of he's homotopy perturbation method (hpm) an approximate solution of velocity eld is derived for the ow in straight pipes of non-newtonian uid obeying the sisko model. the nonlinear equations governing the ow in pipe are for- mulated and analyzed, using homotopy perturbation method due to he. furthermore, the obtained solutions for velocity eld is graphically sketched and compared w...

A fully Lagrangian nite element method for the analysis of Newtonian ows is developed. The approach furnishes, in e ect, a Lagrangian implementation of the compressible Navier–Stokes equations. As the ow proceeds, the mesh is maintained undistorted through continuous and adaptive remeshing of the uid mass. The principal advantage of the present approach lies in the treatment of boundary conditi...

A general purpose package in Mathematica environment for the automatic computation of non-newtonian ow equations is developed and presented. The software allows the user to choose among three coordinate systems and four diierent uid models. Changing of variables, scaling and other formal manipulation of the equations are also possible.

The vortex ow which follows intense sound propagating in a bubbly liquid, is considered. The reasons for acoustic streaming are both nonlinearity and dispersion. That makes streaming especial as compared with that in a Newtonian uid. Conclusions concern the vortex ow induced in a half-space by initially harmonic or impulse Gaussian beam. The vortex ow recalls a turbulent ow with increasing in t...

All spacetimes for an irrotational collisionless uid with a purely electric Weyl tensor, with spacetime curvature determined by the exact Einstein eld equations, are shown to be integrable. These solutions include the relativistic generalisations of the Zeldovich solutions of Newtonian theory. Thus our result shows the consistency of various studies of "silent" universes (where such consistency...

The system of equations describing a nonstationary ow of a quasi-newtonian uid, with temperature dependent viscosity and with the viscous heating, is considered. Existence of at least one weak solution is proved, i.e. we get existence of at least one velocity eld having nite energy and existence of a nonnegative temperature eld. Its regularity is a consequence of the L 1-forcing term generated ...

A numerical method for simulating the extensional dynamics of elongating ®laments of non-Newtonian ̄uids in a ®lament stretching rheometer is presented. The boundary element method, in conjunction with either the Oldroyd-B or the generalized multimode Upper-Convected Maxwell constitutive model, is used to calculate the transient evolution of the liquid interface, the applied force on the station...

The non{linear dynamics of self{gravitating collisionless matter with vanishing vorticity is studied in a general relativistic framework, using synchronous and comoving (i.e. Lagrangian) coordinates. Writing the equations in terms of the metric tensor of the spatial sections orthogonal to the uid ow allows an unambiguous expansion in inverse powers of the speed of light. The Newtonian and post{...

Awell-established numerical approach to solve the Navier–Stokes equations for incompressible žuids is Chorin’s projection method [1], whereby the žuid velocity is explicitly updated, and then an elliptic problem for the pressure is solved, which is used to orthogonally project the velocity eld to maintain the incompressibility constraint. In this paper, we develop a mathematical correspondence...