European Journal of Mechanics B-fluids 

About: European Journal of Mechanics B-fluids is an academic journal published by Elsevier BV. The journal publishes majorly in the area(s): Reynolds number & Turbulence. It has an ISSN identifier of 0997-7546. Over the lifetime, 2565 publications have been published receiving 56952 citations. The journal is also known as: European journal of mechanics. Fluids & EJM. B, Fluids.

Physical Mechanisms of the Rogue Wave Phenomenon

Abstract: A review of physical mechanisms of the rogue wave phenomenon is given. The data of marine observations as well as laboratory experiments are briefly discussed. They demonstrate that freak waves may appear in deep and shallow waters. Simple statistical analysis of the rogue wave probability based on the assumption of a Gaussian wave field is reproduced. In the context of water wave theories the probabilistic approach shows that numerical simulations of freak waves should be made for very long times on large spatial domains and large number of realizations. As linear models of freak waves the following mechanisms are considered: dispersion enhancement of transient wave groups, geometrical focusing in basins of variable depth, and wave-current interaction. Taking into account nonlinearity of the water waves, these mechanisms remain valid but should be modified. Also, the influence of the nonlinear modulational instability (Benjamin–Feir instability) on the rogue wave occurence is discussed. Specific numerical simulations were performed in the framework of classical nonlinear evolution equations: the nonlinear Schrodinger equation, the Davey–Stewartson system, the Korteweg–de Vries equation, the Kadomtsev–Petviashvili equation, the Zakharov equation, and the fully nonlinear potential equations. Their results show the main features of the physical mechanisms of rogue wave phenomenon.

Natural convection cooling of a localised heat source at the bottom of a nanofluid-filled enclosure

Abstract: This article presents a numerical study of natural convection cooling of a heat source embedded on the bottom wall of an enclosure filled with nanofluids. The top and vertical walls of the enclosure are maintained at a relatively low temperature. The transport equations for a Newtonian fluid are solved numerically with a finite volume approach using the SIMPLE algorithm. The influence of pertinent parameters such as Rayleigh number, location and geometry of the heat source, the type of nanofluid and solid volume fraction of nanoparticles on the cooling performance is studied. The results indicate that adding nanoparticles into pure water improves its cooling performance especially at low Rayleigh numbers. The type of nanoparticles and the length and location of the heat source proved to significantly affect the heat source maximum temperature.

Exact solutions for self-similar boundary-layer flows induced by permeable stretching walls

Abstract: The self-similar two-dimensional steady boundary-layer flow induced by a permeable surface stretching with velocity Uw(x)=A·xm in a quiescent fluid in the presence of suction or injection with velocity Vw(x)=a·x(m−1)/2 is considered for A>0 and m>−1. The exact analytic solutions of this problem are given for m=−1/3 and m=−1/2 and the mechanical characteristics of the corresponding flows are discussed in detail. Boundary layers of the same thickness corresponding to different lateral mass fluxes are described. It is shown that to the smallest entrainment velocity, there corresponds a vanishing skin friction, i.e. a `dragless motion' of the fluid. The exact results are also compared with the results of the analytical approximations reported recently by other authors (in a physically different but mathematically identical context) in this journal.