This technical brief presents a numerical study regarding the required development length ðL 1⁄4 Lfd=HÞ to reach fully developed flow conditions at the entrance of a planar channel for Newtonian fluids under the influence of slip boundary conditions. The linear Navier slip law is used with the dimensionless slip coefficient kl 1⁄4 kl l=H ð Þ, varying in the range 0 < kl 1. The simulations were ...

The combined effects of magnetic field, Navier slip and convective heating on the entropy generation in a flow of a viscous incompressible electrically conducting fluid between two infinite horizontal parallel plates under a constant pressure gradient have been examined. Both the lower and upper plates of the channel are subjected to asymmetric convective heat exchange with the ambient fluid. T...

The electroviscous effect has been widely studied to investigate the effect of surface charge-induced electric double layers (EDL) on the pressure-driven flow in a micro/nano channel. EDL has been reported to reduce the velocity of fluid flow and increase the fluid drag. Nevertheless, the study on the combined effect of EDL with large zeta potential up to several hundred millivolts and surface ...

We consider the lubrication model for a thin film driven by competing gravitational forces and thermal gradients on an inclined plane. We are interested in the general traveling wave problem when the Navier slip boundary condition is used. We contrast (1) gravity dominated flow, (2) Marangoni dominated flow, and (3) flow in which the two driving effects balance. For a “singular slip” model we s...

The barotropic compressible Navier–Stokes system subject to the Navier-slip boundary conditions in a general two-dimensional bounded simply connected domain is considered. For initial density allowed vanish, global existence of strong and weak solutions established when shear viscosity positive constant bulk one proportional power with bigger than third. It should be mentioned that this result ...

We present a straightforward method to solve gas damping problems for perforated structures in two dimensions (2D) utilising a Perforation Profile Reynolds (PPR) solver. The PPR equation is an extended Reynolds equation that includes additional terms modelling the leakage flow through the perforations, and variable diffusivity and compressibility profiles. The solution method consists of two ph...

We used atomic force microscopy to study dynamic forces between a rigid silica sphere (radius approximately 45 microm) and a silica nano-particle super-hydrophobic surface (SNP-SHS) in aqueous electrolyte, in the presence and absence of surfactant. Characterization of the SNP-SHS surface in air showed a surface roughness of up to two microns. When in contact with an aqueous phase, the SNP-SHS t...

A domain in R3 that touches the x3 axis at one point is found with following property. For any initial value a C2 class, axially symmetric Navier Stokes equations slip boundary condition have finite energy solution stays bounded for given time, i.e. no time blow up of fluid velocity occurs. The result seems to be first case where Navier-Stokes regularity problem solved beyond dimension 2.

The quasi-neutral limit of the Navier-Stokes-Poisson system modeling a viscous plasma with vanishing viscosity coefficients in half-space $$\mathbb{R}_+^3$$ is rigorously proved under Navier-slip boundary condition for velocity and Dirichlet electric potential. This achieved by establishing nonlinear stability approximation solutions involving strong layer density potential, which comes from br...