LARGE AND SMALL FORCE LIMITS FOR SPINNING WITH FENE DUMBBELL MODELS

Theoretical results for spinning in the limiting cases of very small a nd very large applied force are obtained. The small force limit shows how the Deborah number dependence of the 'spinning viscosity', predict ed for the FENE dumbbell model at low rates of strain, is due to the d ecay of initial stresses rather than to the extensional flow. The larg e force limit is consistent with expected Newtonian behaviour for full y extended dumbbells. The merit of using physically relevant quantitie s in the mathematical manipulation is discussed.