organizzazione dell'evento (scientifica, logistica ecc.)

organizzazione dell'evento (scientifica, logistica, ecc.)

A recent approach to generate a zero divergence velocity field by operating directly on the discretized Navier-Stokes equations is used to obtain the decoupling of the pressure from the velocity field. By following the methodology suggested by Amit, Hall, and Porsching the feasibility of treating three dimensional flows and multiply connected domains is analyzed. The present model keeps the main features of the classical vector potential method in that it generates a divergence-free velocity field through an algebraic manipulation of the discrete equations. At the same time the boundary conditions are still imposed on the discrete values of the primitive variables. The accuracy of the method is tested against the exact solution for a recirculating unsteady flow both in simply and doubly connected domains. Several applications to flow fields in three-dimensional enclosures or in multiply connected domains are presented and discussed in terms of accuracy and efficiency of the method. © 1991.

The non-inertial flow of a shear thinning fluid between intersecting planes is studied using a multi-parameter continuation technique. Unlike the classical linearly viscous fluid, it is found that boundary layers develop even in the case of non-inertial flows in both converging and diverging flow. The boundary layers develop due to the non-linearities in the equation which reflect the fact that the fluid can shear thin. © 1991.

The effects of transverse gravity on steady flow past a split plate are investigated, by adopting the wake model proposed in the preceding paper (I). The existence and uniqueness of the solution as well as the convergence of an iteration process involving the free streamlines are proved for large Froude numbers by means of the Banach contraction mapping principle using Lipschitz norms. © 1986 Birkhäuser Verlag.