939 KB35 KB199920252019Četina, MatjažDomínguez, José M.Novak, GorazdTafuni, AngelŽagar, Dušanletnik:32številka:57str. 107-119ISSN:1581-0267COBISSID_HOST:17264643URN:URN:NBN:SI:doc-W2I7JJGKslFakulteta za gradbeništvo in geodezijoActa hydrotechnica3-D modelCFDDualSPHysicsforceFSIgradbeništvohidrodinamikahidrotehnikahydrodynamicspotopljeno telosileSPHsubmerged bodyDoločitev koeficienta upora potopljenega telesa z uporabo metode SPH| Evaluation of the drag coefficient of a fully submerged body using SPH|The open-source software DualSPHysics was used so set up a three-dimensional model of a free-surface water flow in a narrow horizontal open channel with a rectangular cross section, and to determine the forces acting on various submerged fixed objects. Simulations included a sphere, a cube, and a composite capsule-like object made out of three basic bodies. Objects were located in the channel's central axis at various distances from the channel bed, and were exposed to various flow velocities. Calculating the hydrodynamic forces acting upon the objects resulted in longitudinal forces increasing with the square of the velocity, transverse forces equal to zero, and constant vertical forces. The calibrated and validated model was used to evaluate the drag coefficient of the submerged composite capsule-like object. This research reveals certain limitations of DualSPHysics and facilitates future improvements of the code and the upgrade of studies related to vertical slot fishwaysOdprtokodno programsko opremo DualSPHysics smo uporabili za trodimenzijsko modeliranje vodnega toka s prosto gladino v ozkem vodoravnem odprtem kanalu pravokotnega prečnega prereza z namenom določitve sil, ki delujejo na različne mirujoče potopljene objekte. Simulacije so obravnavale obtekanje mirujoče krogle, kocke in kapsuli podobnega telesa, sestavljenega iz treh osnovnih geometrijskih teles. Obravnavali smo različne globine potopitve in različne hitrosti vodnega toka. Izračunane vzdolžne sile naraščajo s kvadratom hitrosti, prečne so enake nič, navpične pa konstantne. Z umerjenim in verificiranim modelom smo izračunali koeficient upora za potopljeno sestavljeno telo. Raziskava je pokazala na nekatere omejitve pri uporabi orodja DualSPHysics in bo pripomogla k nadaljnjemu razvoju kode in nadgradnji raziskav toka v ribji stezi z vertikalnimi prekatiTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaUniverza v Ljubljani, Fakulteta za gradbeništvo in geodezijo