The location of the gas-melt interface resulting from gas injection is then approximated by the isovel of an appropriately defined mean velocity on a plane perpendicular to the principal flow direction.
The contour of fictitious concentration [psi] = 0.5 represents the interface location prediction by the full analysis, and the isovel contour v/[bar.v] = 1 the short cut prediction.
This is probably because it results in an adjustment to the isovel position over the whole channel cross section, whereas a more localized correction is needed in this case.
The approach is based on steady-state flow analysis for a single fluid (polymer melt) and the identification of an appropriately chosen isovel of the flow.
Variations in wall shear rate are reflected in the location of isovels of the developed flow on the channel cross section.
8) Non-rotating nip walls with [[a.sup.f].sub.2,n6], which is assumed to be a curve formed on the melt surface along the isovel of [V.sub.yz]/[V.sub.bz] = 0.5 according to the authors 
Dl, the non-rotating nip wall with [[a.sup.fc].sub.2,n6] was assumed to be formed along the isovel of [V.sub.yz]/[V.sub.bz] = 0.5 according to the authors (5), and a width element dl at x is
The variation in near-surface wind flow isovels was drawn for each cross profile of the coast.
On the basis of the variations in wind velocity at different heights it is estimated that, from the middle point of the beach towards the foredune toe, the wind velocity within the 0.2-1.0 m layer decreased as a result of changes in topography and the presence of marram grass, but increased (convergence in upper isovels of the wind flow) above that level (1.5-2.0 m) (Fig.
On the brink of the cliff crest, because of the generated streams ascending along the steep slope (58[degrees]) as well as the appearing grass cover, the wind velocity decreased dramatically at the height of 0.2 m, while at a higher level (0.5-2.0 m) it increased significantly (convergence in isovels of the wind flow; Fig.
Up the slope, the wind velocity at 0.2 m continued to decrease due to the occurrence of marram grass, while in the higher layers it increased because of the convergence of isovels over the incipient dune crest (Fig.
However, [U.sup.*] increases at the stoss slope of a foredune where wind isovels become compressed, reaching 0.44-1.28 m [s.sup.-1].