Authors Tsamopoulos J., Dimakopoulos Y., Chatzidai N., Karapetsas G., Pavlidis M. Abstract We examine the buoyancy-driven rise of a bubble in a Newtonian or a viscoplastic fluid assuming axial symmetry and steady flow. Bubble pressure and rise velocity are determined, respectively, by requiring that its volume remains constant and its […]
2008
4 posts
Authors Housiadas K., Tsamopoulos J. Abstract The effect of the air jet, which is used to increase the process stability and cool the polymeric film which is produced by the widely-used Film Blowing Process (FBP) is presented. The air jet is supplied circumferentially and tangentially on the outside surface of […]
Authors Dimakopoulos Y., Pavlidis M., Tsamopoulos J. Abstract We examine the pressure-driven coating of a straight tube with a viscoelastic liquid using an advanced and stable finite element algorithm, which is based on an elliptic grid generator along with local refinement and reconstruction of the mesh wherever this is needed. […]
Authors Karapetsas G., Tsamopoulos J. Abstract The steady extrusion of viscoelastic materials from a straight, annular die is studied theoretically. The viscoelastic behavior is modelled using the affine Phan-Thien and Tanner (PTT) constitutive equation of the exponential form. For the numerical solution of the governing equations the mixed finite element […]