| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 7625 |
| title | Model of particle-particle interaction for saltating grains in water |
| authors | Włodzimierz Czernuszenko |
| pages | 101 — 120 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem56str101.pdf |
| keywords | Lagrangian model, saltation, particle motion, dense flow, particle collision |
| affiliations | - Institute of Geophysics, Polish Academy of Sciences 01-452 Warszawa, Ks. Janusza 64, Poland, e-mail: wczer@igf.edu.pl
|
| abstracts | A model of particle-particle interaction for bed sediment-laden flows, based on impulse
equations, is presented. The model is applicable to dense flows in which particle motion is
dominated by collisions. The model takes into account the possibility of sliding during the
collision process. However, particle rotation is not considered in this model. The governing
equations do not incorporate dimension of angular momentum. To verify this model, calculation
of post-collision velocities was performed for several different collision simulations.
The term of particle-particle interaction is implemented into a general Lagrangian model
of trajectory of a sediment grain in a fluid flow. This general Lagrangian model is written
according to Newton’s second law; the rate of change of momentum of a particle is balanced
against the surface and body forces. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 7626 |
| title | Flood routing by the non-linear Muskingum model: conservation of mass and momentum |
| authors | Dariusz Gąsiorowski |
| pages | 121 — 137 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem56str121.pdf |
| keywords | flood routing, non-linear Muskingum equation, mass and momentum balance, conservative form |
| affiliations | - Faculty of Civil and Environmental Engineering, Gdańsk University of Technology, ul. Narutowicza 11/12, 80-233 Gdańsk, Poland, e-mail: gadar@pg.gda.pl
|
| abstracts | In this paper, the conservative properties of the Muskingum equation, commonly applied to
solve river flood routing, are analysed. The aim of this analysis is to explain the causes of
the mass balance error, which is observed in the numerical solutions of its non-linear form.
The linear Muskingum model has been considered as a semi-discrete form of the kinematic
wave equation and therefore it was possible to derive its two non-linear forms. Both forms
were derived directly from the kinematic wave equation. It appeared, that depending on the
assumed conservative form of the Muskingum equation, this model satisfies either the global
mass conservation law or the global momentum conservation law. Both laws are satisfied
simultaneously by the linear equation only. The mass balance error can be eliminated from
the numerical solution on condition that the non-linear Muskingum equation is written in
the proper conservative form. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|
| type | A |
| database id | 7627 |
| title | Numerical simulations of triaxial test with sand using DEM |
| authors | Łukasz Widuliński, Jan Kozicki, Jacek Tejchman |
| pages | 149 — 171 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem56str149.pdf |
| keywords | discrete element model, rolling resistance, sand, triaxial test |
| affiliations | - Faculty of Civil and Environmental Engineering, Gdańsk University of Technology, ul. Narutowicza 11/12, 80-233 Gdańsk, Poland, e-mails: lwidul@pg.gda.pl, jkozicki@pg.gda.pl, tejchmk@pg.gda.pl
|
| abstracts | Numerical simulations of the behaviour of cohesionless sand were carried out using a discrete
element method. A drained triaxial test of a homogeneous sand specimen under constant
lateral pressure was modelled. To simulate the behaviour of sand, a 3D spherical discrete
model YADE was used, enhanced by including rolling resistance in order to take into account
grain roughness. Numerical results were directly compared with corresponding laboratory
tests. The effects of lateral pressure, initial void ratio and micro-parameters on the global
behaviour of sand were investigated. |
| attributes | [reviewed] [scientific] |
| language | en |