Heat transfer plays an important role in the handling and processing of non-Newtonian nanofluids. In this paper, the fully developed flowof an incompressible, thermodynamically compatible non-Newtonian third-grade nanofluid in coaxial cylinders is studied. Two illustrative models of variable viscosity, namely (i) Reynolds’ model and (ii) Vogel’s model, are considered. Analytic solutions of velo...

We show that rapidly rotating cylinders sliding on smooth surfaces can exhibit novel trajectories. The lateral deflection can be as large as the net displacement in the initial direction of motion. With a large enough initial angular speed, the cylinder can trace out a spiral trajectory having a large number of loops. An exact analytical result for large lateral deflection is also derived.

We investigate the stability of a fluid confined between two cylinders that rotate at same constant angular speed. In the case of infinite cylinders, or endwalls rotating with the cylinders, the flow is in solid-body rotation and hence linearly stable for any rotation speed. However, when the endwalls are stationary, a large-scale circulation is driven by radially inward boundary layer flow on ...

Ferrofluid spin-up flow has been studied in finite height cylinders and spheres subjected to a uniform rotating magnetic field. Ultrasound measurements in finite height cylinders with a free surface show the presence of surface driven flows as well as bulk flows. In finite height cylinders with a cover, only bulk flows exist. Ultrasound measurements in fully filled spheres of ferrofluid give ne...

Differential rotation occurs in conducting flows in accretion disks and planetary cores. In such systems, the magnetorotational instability can arise from coupling Lorentz and centrifugal forces to cause large radial angular momentum fluxes. We present the first experimental observation of the magnetorotational instability. Our system consists of liquid sodium between differentially rotating sp...

Experimental evidence proves that polymer-stabilized blue phase liquid crystal is not perfectly optically isotropic. The optical rotatory power (ORP) of double twist cylinders causes the polarization axis of the transmitted light to rotate a small angle, and leaks through the crossed polarizers. Rotating the analyzer by ~2 to correct this ORP can improve the contrast ratio by 3X. Author