STUDY ON THE SHEAR STRESS AND NORMAL STRESS DIFFERENCE OF FOAMS

A theoretical stress tensor model that includes surface tension forces and viscous forces is developed by considering the three-dimensional spatially periodic cells of dodecahedron. Meanwhile, the shear stress and normal stress difference under various shear rates are calculated by computer.The rheological properties of foam have been measured by RMS-605 Rheameter, Rotary Viscositymeter-2 (Rv-2) and Capillary Rheometer. The theoretical results are close to the experimental data when the effect of slip at vi...