Elongational properties of liquids in contraction flow

Flows through contraction geometries (contraction flows) are found in many fields involving fluids, but they poorly understood because have two inseparable aspects as a whole: shear flow and elongational flow. In this paper, we focus on the center line of where component vanishes symmetry field clarify properties liquids using data obtained to date. First, show images flows water dilute polymer solutions, then, continuity equation is used obtain expressions for center-line velocity. The represent either exponential (ECF) or linear (LCF) agree well with experimental results It suggested that Deborah number plays an important role deciding ECF LCF. For solutions polyethylene oxide polyacrylamide, ratio viscosity (μe) (μs) be high, order 104 103, respectively. On other hand, molten 5.0-wt. % polyisobutylene hydrocarbon tetradecane greatly different values μe μs, their μe/μs do not differ much from four. We propose novel relaxation velocity (RV) find exponent ai velocity-profile correlated log10RV water, polyethylene. Furthermore, wet spinning. spinning model solutions.