-The unsteady similarity equations have been obtained for a disk rotating in a viscous fluid that decelerates with angular velocity proportional to time. The resulting ordinary differential equations have been solved numerically using an easy numerical technique for range 0 100    s of the non-dimensional parameter s which measures unsteadiness. The calculations have been carried out using t...

A class of exact general relativistic rotating thick disks surrounded by rotating dust is constructed by applying the “displace, cut, fill and reflect” method on the van Stockum class of metrics. Two particular solutions are considered in detail. We find that the disks have annular regions with negative energy density and heat flow is present in most of the radial extension of the disk. It is s...

The roles of chemical kinetics and mass transfer in two types of bioreactors (packed-column reactors and rotating disk bioreactors), used with continuous-flow sample/ reagent(s) processing, are discussed in detail. A normalized quantitative comparison between these types of reactors clearly shows that rotating disk reactors afford a significantly more efficient utilization of immobilized active...

The two known exact solutions of Einstein’s field equations describing rotating objects of physical significance – a black hole and a rigidly rotating disk of dust – are discussed using a single mathematical framework related to Jacobi’s inversion problem. Both solutions can be represented in such a form that they differ in the choice of a complex parameter and a real solution of the axisymmetr...

A theoretical investigation into the vortex-speed selection within the rotating-disk boundary layer is conducted. Two methods are used which are different to previous investigations in the literature and enable analysis of a particular vortex speed with respect to the rotating surface. Using these methods (together with arguments based on critical Reynolds numbers, unstable parameter ranges and...

Previous studies demonstrated an aftereffect of walking on a rotating treadmill, involving inadvertent circular navigation with eyes closed [podokinetic after-rotation (PKAR)]. We compared PKAR following unilateral and bilateral podokinetic (PK) stimulation to determine whether the left and right legs could be independently adapted. Each subject performed two sessions of PK stimulation, steppin...