research in convective heat transfer using suspensions of nanometer-sized solid particles in base liquids started only over the past decade. recent investigations on nanofluid, as such suspensions are often called, indicate that the suspended nanoparticles remarkably change the transport properties and heat transfer characteristics of the suspension. bending walls can also improve heat transfer...

An experimental and numerical study of free convection heat transfer from a channel consisting of a vertical sinusoidal wavy surface and a vertical flat plate has been carried out. The vertical wavy surface was maintained at a constant temperature, while the flat plate is adiabatic. A Mach-Zehnder Interferometer was used to determine the local heat transfer coefficients of sinusoidal wavy surfa...

The shape of the interface between two superimposed layers in a two-dimensional channel confined between a planar and a corrugated or indented wall is investigated in the limit of Stokes flow. A perturbation analysis for walls with small-amplitude sinusoidal corrugations reveals that an insoluble surfactant amplifies the deformation of the interface and causes a negative drift in the phase shif...

In this paper the effect of wall waviness of side walls in a two-dimensional wavy enclosure is numerically investigated. Two vertical wavy walls and straight top wall are kept isothermal and the bottom wall temperature is higher and spatially varying with cosinusoidal temperature distribution. A computational code based on Finite-volume approach is used to solve governing equations and SIMPLE m...

A numerical model is developed to quantify the effects of hydrodynamics on heat and mass transfer during an absorption, for a laminar film flowing over a wavy wall column. First of all, the modelling is written for a single wave of the wall shape. Then, an experimental set up, composed of a CCD video camera, validates this model. Finally, the model is extended to an entire column. The results i...

In this paper, natural convection heat transfer of CuO-water Nanofluid within a wavy-walled cavity and subjected to a uniform magnetic field is examined by adopting the lattice Boltzmann model. The left wavy wall is heated sinusoidal, while the right flat wall is maintained at the constant temperature of Tc. The top and the bottom horizontal walls are smooth and insulated against heat and mass....

This paper concerns laminar countercurrent gas–liquid ow over a wavy wall column, in the case of a falling liquid lm. The modelling concerns the coupling of hydrodynamic and heat and mass transfer for an absorption as an example of application. The falling liquid lm interacts, through the free interface, with the gas phase. The wavy surface generates particular hydrodynamic conditions with the ...

The effects of orientation on flow boiling critical heat flux (CHF) were investigated using high-speed video and microphotographic techniques. Interfacial features were measured just prior to CHF and statistically analyzed. A dominant wavy vapor layer regime was observed for all relatively high-velocities and most orientations, while several other regimes were encountered at low velocities, in ...

Amagnetohydrodynamic flow of a viscous, incompressible and slightly conducting fluid is developed between a parallel flat wall and a wavy wall whereas at the same time fluid is continuously sucked through the flat wall with a constant suction velocity. The velocity and temperature distribution are determined alongwith the pressure gradient and co-efficient of skin friction.

We report on the isogeometric residual-based variational multiscale (VMS) Large Eddy Simulation of a fully developed turbulent flow over a wavy wall. To assess the predictive capability of the VMS modeling framework, we compare its predictions against the results from direct numerical simulation (DNS) and, when available, against experimental measurements. We use C quadratic B-spline basis func...