Abstract: This paper deals with the influence of slip condition on a thin film flow of a third order fluid. We investigate the thin film flow of non-Newtonian fluid (i) when moves down an inclined plane and (ii) when moves on a moving belt with slip condition using the traditional perturbation technique and HPM. The results obtained using both techniques are compared. The expressions for volume...

The local asymptotic behaviour at the stick-slip singularity is determined for the Giesekus fluid in the presence of a solvent viscosity. In planar steady flow, the method of matched asymptotic expansions is used to show that it comprises a three region structure. Specifically, an outer or core region that links boundary layers at the rigid stick and free slip surfaces. In the outer region, the...

Polymer – surface interactions strongly influence many important industrial and rheological flows. In particular, polymer melts and solutions slip against the surface; this has long been associated with sharkskin and spurt in extrusion, and recent experimental observations suggest that slip also plays a role in the formation of enhanced concentration fluctuations in entangled polymer solutions....

This work provides analytical and numerical solutions for the linear, quadratic and exponential Phan–Thien–Tanner (PTT) viscoelastic models, for axial and helical annular fully-developed flows under no slip and slip boundary conditions, the latter given by the linear and nonlinear Navier slip laws. The rheology of the three PTT model functions is discussed together with the influence of the sli...

The flow of a compressible fluid with slip through a cylinder with an asymmetric local constriction has been considered both numerically, as well as analytically. For the numerical work, a particle-based method whose dynamics is governed by the multiparticle collision (MPC) rule has been used together with a generalized boundary condition that allows for slip at the wall. Since it is well known...

We investigate the statistical properties of single phase slip events observed in vortex nucleation experiments in He by the groups in Berkeley and Paris. From the cumulative distribution function of the events we calculate the slip rate as a function of flow velocity. The critical velocity is defined as the mean velocity and its statistical width as the standard deviation. From the slip rate a...

One of the more enigmatic features of the Earth’s style of mantle convection is plate tectonics itself, in particular the existence of strike-slip, or toroidal, motion. Toroidal motion is uncharacteristic of basic thermal convection, but necessarily forms through the interaction of convective flow and nonlinear rheological mechanisms. Recent studies have implied that the empirically determined ...

Rarefied gas slip microflow and heat transfer in rectangular microchannels and backward facing steps are numerically investigated. A control-volume based numerical method is used to solve the Navier–Stokes and energy equations with velocity-slip and temperature-jump conditions at the walls. The effects of Knudsen number (Kn ! 0.1), thermal creep, and viscous heating on the velocity and temperat...

Maxwell’s original slip boundary condition is widely misapplied in current rarefied gas flow calculations (e.g. in hypersonics, microfluidics). If its commonly-accepted form is applied in simulations of gas flows over curved or moving surfaces, crucial physics can be lost. We give examples of such cases. We also propose a new higher-order boundary condition which is based on Maxwell’s original ...