In this paper, the flow due to a rotating disk non-symmetrically placed with respect to the height of the enclosing stationary cylinder is analyzed numerically. The full Navier-Stokes equations expressed in terms of stream function and vorticity are solved by successive over-relaxation for different disk radii, its distance from the bottom casing and rotational Reynolds numbers. It is observed that the flow pattern is strongly influenced by the size and the position of the disk. When the disk is very close to the top casing and small in radius, there are two regions of different scales and the vortices in the region of small scale are trapped between the disk and the top casing. Further, the variation of the moment coefficient is determined for different positions and sizes of the rotating disk. The calculations shows that the frictional torque increases rapidly, when the disk approaches the top casing. This finding is of importance for the design of vertical rotating disk reactors applied in chemical vapor deposition.

Flow induced by an asymmetrically placed disk rotating coaxially inside a cylindrical casing

The paper contains an analysis of the distribution of stress and couple stress in a semi-infinite elastic laminated body when the body is deformed on the first plate due to surface pressure. In this analysis, the boundary conditions at the surface of the arbitrary numbered plate have been given without application of shearing stress nor couple stress, and the material constantsG, v andl on the all plates are taken as the same values. The particular solution of this case is constructed by applying the method of V. H. Bufler's recurrence relations for a stress transfer function with the aid, of displacement continuity. The problem is numerically calculated with three different new material constants and Poisson's ratiov=0.3; and in the results, the reduction rate of σzz in comparison with the classical value and μzθ distributions are influenced by the materials to a large degree.

K. Yoshikawa

Papers

Stress analysis for a laminated half-body in couple stress theory