FINITE ELEMENT ANALYSIS OF THE FREE EXTRUSION FLOWS OF BOGER FLUIDS

The stream-line finite element method proposed by Luo and Tanner has been improvedand used to simulate the extrudate swell of the so called Boger fluid.The element withdiscontinuous pressure proves to be a successful choice and superior to that with continuous pressureIt is revealed that the visccsity of Newtonian solvent of the Boger fluid has a great influence on thecalculated swelling.The Weissenberg number is suggested to take the place of recoverable shear strainin Tanner′s formula to estimate the swelling of the Boger or Oldroyd-B fluids.     

非牛顿流体流动的数值模拟及落球的实验研究

研究了圆球在Oldroyd-B流体及半浓纤维Oldroyd-B流体悬浮液中的流动。计算了落球的阻力系数和应力场。同时讨论了几种非牛顿流体流动的数值模拟中的有限元格式。