Small-amplitude oscillations of viscous, capillary bridges are characterized by their frequency and rate of damping. In turn, these depend on the surface tension and viscosity of the liquid, the dimensions of the bridge, the axial and azimuthal wavenumbers of each excited mode and the relative magnitude of gravity. Both analytical and numerical methods have been employed in studying these effects. Increasing the gravitational Bond number decreases the eigenvalues in addition to modifying the well-known Rayleigh stability limit for meniscus breakup. At high Reynolds numbers results from inviscid and boundary-layer theories are recovered. At very low Reynolds numbers oscillations become overdamped. The analysis is applicable in measuring properties of semiconductor and ceramic materials at high temperatures under well-controlled conditions. Such data are quite scarce.

Finite-amplitude, forced and free oscillations of capillary bridges are studied. They are characterized by a resonant frequency and a damping rate which, in turn, depend on fluid properties, dimensions of the bridge, gravitational force relative to surface tension and amplitude of the external disturbance. The Navier–Stokes equations are solved numerically using the Galerkin/finite-element methodology for discretization in space and implicit finite differences with adaptive time stepping for discretization in time. It is found that the resonant frequency decreases and the damping rate increases almost linearly with the oscillation amplitude. Their relative changes from their corresponding values at infinitesimal amplitude depend on fluid properties and dimensions of the bridge. Moreover, careful measurement of the resonant frequency and damping rate in a well-controlled experiment may provide quite accurate values for properties of the liquid over a wide range of modified Reynolds numbers.

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In this article, the kinetics of crystallization for semi-crystalline polymers has been successfully incorporated into a cavity flow simulation. The flow resistance, in terms of filling pressure, can be significantly underestimated if crystallization is neglected during the calculation. In addition, the filling behavior for nucleated semi-crystalline materials is quite different from that of its virgin counterpart. With this simulation, the crystallinity distribution and degree of crystallinity in the part can be predicted at any instant of processing time, and hence part quality can be predicted accordingly.

Owing to a printing error all the sizes of the arrows on figures 8,13, and 16 that indicate the scale for the velocity vectors have length equal to 3 mm. This is incorrect. The corrected lengths are listed in the following table.