Home > Search Results: 999C1a:GA103/09/2066
Search:
Search Tips :: Advanced Search
Search collections:
Sort by: Display results: Output format:
National Repository of Grey Literature 4 records found  Search took 0.00 seconds. 
A note to the simplification in description of some molecular-based polymer models
 Kharlamov, Alexander ; Filip, Petr
One type of integral is frequently met in various description of behaviour of polymer materials through molecular-based models starting with the classical Doi-Edwards one. The integrand in this integral for which an integrated region represents a solid angle is formed by a product of a unit vector (pointed at an element of this region) with a deformation gradient tensor. This product is raised to an exponent that is not usually an integer. The aim of this contribution is to derive substantially simplified expression for this integral respecting high accuracy of an approximation.
Detailed record
A note to the tube theory
 Kharlamov, Alexander ; Filip, Petr ; Švrčinová, Petra
The classical Doi-Edwards (DE) model represents a basic issue for tube theories. The model describes dynamics of polymer strands between entanglements and predicts stress in linear polymers. In this contribution there is considered the dynamics of the whole molecules within the same tube picture. When the molecule end-to-end vector is considered as a Hookean spring the damping function shows weaker thinning. The presented model describes one of the possible mechanisms leading to weaker damping exhibited by branched polymers.
Detailed record
Určení objemového průtoku vazkoplastických kapalin mezikružím za pomoci aditivní metody
 Filip, Petr ; David, Jiří
An additive method enabling a direct determination of axial flow rate for viscous (power-law model) and viscoplastic (Vočadlo model) fluids in concentric annuli is presented. Flow rate through the actual concentric annulus is possible to express as a sum of axial flow rates through individual partial concentric annuli forming the whole annulus. The resulting relation for axial flow rate is possible to express in analytical forms without necessity of otherwise complicated derivations. The only numerical calculation consists in a determination of location of a zero shear stress for the original whole concentric annulus.
Detailed record
Poznámka k reptační teorii
 Kharlamov, Alexander ; Filip, Petr ; Švrčinová, Petra
Avoiding the Independent Alignment (IA) approximation in the classical Doi-Edwards model causes the computation extremely time and hardware consuming. Nevertheless some flow situations cannot be modelled with the IA approximation. This contribution presents a probabilistic approach not taking into account the IA approximation.
Detailed record

Interested in being notified about new results for this query?
Subscribe to the RSS feed.
Digital Repository :: Search :: Submit :: Personalize :: Help
Powered by Invenio v1.1.2
Maintained by admin.invenio@techlib.cz
This site is also available in the following languages:
Česky  English