Axisymmetric Flow-induced Birefringence Measurements for the Flow of a Polystyrene Boger Fluid into an Abrupt Contraction-expansion
نویسندگان
چکیده
We study the creeping flow of a dilute, monodisperse polystyrene/oligomeric styrene Boger fluid through axisymmetric abrupt contraction-expansions of various contraction ratios and over a wide range of Deborah numbers. Measurements of the entry pressure drop for the polystyrene solution increase monotonically with Deborah number and are substantially larger than those observed for a similar Newtonian fluid. Axisymmetric flow-induced birefringence measurements upstream of the 4:1:4 contraction-expansion show a region of strong polymer chain extension which increases in strength and in size with Deborah number. Downstream measurements reveal a region of axial compression whose size and position are independent of Deborah number.
منابع مشابه
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