Flows of viscoplastic materials: Models and computations

Papanastasiou, TC; Boudouvis, AG

dc.contributor.author	Papanastasiou, TC	en
dc.contributor.author	Boudouvis, AG	en
dc.date.accessioned	2014-03-01T01:12:56Z
dc.date.available	2014-03-01T01:12:56Z
dc.date.issued	1997	en
dc.identifier.issn	0045-7949	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/12284
dc.subject	Finite Element	en
dc.subject	Finite Element Method	en
dc.subject	Material Model	en
dc.subject	Newton Iteration	en
dc.subject.classification	Computer Science, Interdisciplinary Applications	en
dc.subject.classification	Engineering, Civil	en
dc.subject.other	Computer simulation	en
dc.subject.other	Finite element method	en
dc.subject.other	Flow of solids	en
dc.subject.other	Iterative methods	en
dc.subject.other	Galerkin method	en
dc.subject.other	Viscoplasticity	en
dc.title	Flows of viscoplastic materials: Models and computations	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0045-7949(96)00167-8	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0045-7949(96)00167-8	en
heal.language	English	en
heal.publicationDate	1997	en
heal.abstract	Flows of materials with yield are analysed by using a continuous viscoplastic equation (CVE) that eliminates the necessity of tracking material yield surfaces. These flows are computed by means of the Galerkin/finite element method and global Newton iteration. Numerical difficulties stemming from the sigmoidal form of the CVE are avoided by appropriate selection of the initial estimation to the Newton iteration, or by solution continuation in the space of the exponential material parameter of the CVE. Simultaneously with the determination of the unknown velocity and pressure fields, the finite element scheme locates the characteristic material lines, such as interfaces and yield surfaces. Results are presented for two-dimensional flows over generalized flow conduits at driving gradients below and above yielding. It is shown that a general viscoplastic held consists of truly unyielding plug regions (UPR) carried by yielded flowing films (YFF) in contact with solid boundaries or intervening apparent unyielded regions (AUR). (C) 1997 Civil-Comp Ltd and Elsevier Science Ltd.	en
heal.publisher	PERGAMON-ELSEVIER SCIENCE LTD	en
heal.journalName	Computers and Structures	en
dc.identifier.doi	10.1016/S0045-7949(96)00167-8	en
dc.identifier.isi	ISI:A1997XG83100053	en
dc.identifier.volume	64	en
dc.identifier.issue	1-4	en
dc.identifier.spage	677	en
dc.identifier.epage	694	en