On Fluid Resistance of Enclosed Rotating Rough Surface Disc

Polygons on a rotating fluid surface.

We report a novel and spectacular instability of a fluid surface in a rotating system. In a flow driven by rotating the bottom plate of a partially filled, stationary cylindrical container, the shape of the free surface can spontaneously break the axial symmetry and assume the form of a polygon rotating rigidly with a speed different from that of the plate. With water, we have observed polygons...

Boundary Layers and Heat Transfer on a Rotating Rough Disk

The study of flow and heat transfer over rotating circular disks is of great practical importance in understanding the cooling of rotatory machinery such as turbines, electric motors and design and manufacturing of computer disk drives. This paper presents an analysis of the flow and heat transfer over a heated infinite permeable rough disk. Boundary-layer approximation reduces the elliptic Nav...

Frictional torque on a rotating disc

Resistance to motion often includes a dry frictional term independent of the speed of an object and a fluid drag term varying linearly with speed in the viscous limit. (At higher speeds, quadratic drag can also occur.) Here, measurements are performed for an aluminium disc mounted on bearings that is given an initial twist and allowed to spin until it comes to a stop. It is found that a sum of ...

Flow transitions in the surface switching of rotating fluid

Magnetohydrodynamic Flow due to a Stretching Surface in Rotating Fluid

In this study, we investigate analytical treatment of three dimensional MHD viscous flow in a rotating frame. The flow is generated due to uniform stretching of a sheet in x direction. Analytic solution is obtained through peturbation method after transforming the governing partial differential equation to ordinary differential equation using suitable similarity transformations. Graphs are plot...