A purely irrotational theory of the effect of viscosity on the decay of free gravity waves is derived and shown to be in excellent agreement with Lamb’s (1932) exact solution. The agreement is achieved for all waves numbers k excluding a small interval around a critical k=kc where progressive waves change to monotonic decay. Very detailed comparisons are made between the purely irrotational and...

We demonstrate a family of two-dimensional steady viscous flows which have singular continuous (fractal) Fourier spectra. Such flows represent a novel intermediate stage between order and Lagrangian chaos: The motion of individual fluid particles in them is neither entirely correlated nor completely disordered. In the considered setup these flows are presented by the exact solutions of the Navi...

Abstract: This paper reports about progress in the development of numerical tools for adaptive aerodynamic configuration design. We try to illustrate the use of new software components allowing for the parameterized modelling of boundary conditions and the simulation of compressible steady and unsteady viscous flows including a computational flow control model. A coupling of these tools and the...

This paper presents a robust and automated approach to generate unstructured hybrid grids comprised of prismatic and tetrahedral elements for viscous flow computations. The hybrid mesh generation starts from a triangulated surface mesh. The prismatic elements are extruded based on the weak solutions of the Eikonal equation to generate anisotropic elements at boundaries, and finally the isotropi...

This article presents the heat and mass transfer characteristics of unsteady MHD flow of a viscous, incompressible and electrically conducting micropolar fluid in the presence of viscous dissipation and radiation over a porous stretching sheet with chemical reaction. The governing partial differential equations (PDEs) are reduced to ordinary differential equations (ODEs) by applying suitable si...

The present numerical attempt deals the sway to transfer of heat and mass characteristics on the time-dependent hydromagnetic boundary layer flow of a viscous fluid over an exponentially inclined preamble stretching. Furthermore, the role of viscous heating, thermal radiation, uneven energy gain or loss, velocity slip, thermal slip and solutal slips are depicted. The prevailing time-dependent P...

The flow characterized by a linear longitudinal velocity field ux(x,t) = a(t)x, where a(t) = a0/(1+a0t), a uniform density n(t) ∝ a(t), and a uniform temperature T (t) is analyzed for dilute granular gases by means of a BGK-like model kinetic equation in d dimensions. For a given value of the coefficient of normal restitution α , the relevant control parameter of the problem is the reduced defo...