Smoothed Particle Dynamics Methods for the Simulation of Viscoelastic Fluids

Content Provider	Semantic Scholar
Author	Ellero, Marco
Copyright Year	2004
Abstract	gave me the possibility to join his group in Madrid and for having introduced me to the field of complex mesoscopic fluid dynamics. The time spent there has been for me an invaluable professional and human experience. I am also very grateful to Dr. Patrick Ilg and Dr. Jose Cifre Hernandez for the stimulating conversations and discussions which we had in the last years. Of course, the same acknowledgment goes to all the people in my group: Igor Stankovic, Haiko Steuer and Nana Sadowsky. I would like to thank specially Eloisa for her appreciable interest in listening to abstruse problems of fluid mechanics and of course for her love support. Another thank goes also to all the friends of 'Kinzo'. My remember of Berlin could not be separated from them. Finally, the most particular acknowledgment goes to my father Ennio and my mother Bruna. Without their constant love, presence and encourage I would not simply be here. 2 3 Abstract This thesis is devoted to analytical and numerical studies of viscoelastic fluids. In first instance, a numerical scheme based on the Smoothed Particle Hydrodynamics method (SPH) is developed. The viscoelasticity is introduced macroscopically by incorporating a corotational Maxwell model for the stress tensor into the hydrodynamics equations. Numerical results are presented for a channel and shear flows in simple bulk and complex geometries. Whenever possible, the results are compared with analytical solutions. Furthermore, a viscoelastic material interacting with a periodic structure of rigid non-rotating cylindrical inclusions is investigated. The analysis of the multi-inclusion problem, widely used to model composite materials characterised by an internal microstructure, shows that the effective shear viscosity exhibits an increase which is linearly proportional to the volume concentration of the inclusions. The second part is focused on the mesoscopic level of description. If the physical scales of the problem are smaller than a typical length, thermal fluctuations become relevant for the description of the system. As a numerical scheme at this level the Dissipative Particle Dynamics (DPD) is used. The mesoscopic model derived via DPD by ten Bosch for the study of polymer flows is generalised. The complex behaviour of polymeric fluids is captured by introducing an additional variable associated with each particle, thus collecting the elastic information about the fluid at scales " within " the dissipative particles. The ten Bosch model suffers from some conceptual shortcomings: it is not thermodynamically consistent, it is not …
File Format	PDF HTM / HTML
DOI	10.14279/depositonce-864
Alternate Webpage(s)	https://depositonce.tu-berlin.de/bitstream/11303/1161/1/Dokument_21.pdf
Alternate Webpage(s)	https://doi.org/10.14279/depositonce-864
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article