48 KB781 KB51 KB199920252001Jošt, DragicaŠkerget, Leopold13 straništevilka:2letnik:47str. 70-82ISSN:0039-2480COBISSID:4612123URN:URN:NBN:SI:doc-34NPRFRNenslAssociation of Mechanical Engineers and Technicians of Slovenia et al.Zveza strojnih inženirjev in tehnikov Slovenije et al.Strojniški vestnikanalize tokaFrancisove turbineizkoristek turbinmodelimodeli turbulentnitokovne razmereturbineturbine francisoveturbulentni tokNapoved izkoristka francisove turbine z numeričnim izračunom toka| Using numerical flow analysis to predict the efficiency of a Francis turbine|This paper presents a numerical analysis of flow in a Francis turbine. We concentrate on flow -energy losses and efficiency prediction. The results, obtained by a separate analysis of each turbine component, are compared with the results of a separate analysis of flow in a spiral casing end a simultaneous calculation of the flow through the other turbine parts. After this we analysed flow in a Francis turbine at several operating points, an efficiency hill-chart diagram was drawn and compared with the measured one. The some calculation was made for a case where no measured iniet conditions were available. The effect of the grid density and turbulence models on the results is also presentedV prispevku je predstavljena numerična analiza toka v francisovi turbini. Osredotočili smo se na napoved energijskih izgub v toku in napoved izkoristka turbine. Rezultate, dobljene z ločeno analizo toka v vsakem delu turbine, smo primerjali z rezultati ločenega izračuna toka v spirali in skupnega izračuna toka skozi preostalo turbino. Nato smo izračunali tok v francisovi turbini v večjem številu obratovalnih točk, narisali školjčni diagram izkoristka in ga primerjali z izmerjenim. Enak izračun je bil narejen še za primer, ko nimamo izmerjenih vztopnih podatkov. V prispevku je predstavljen tudi vpliv gostote mreže in izbire turbulentnega modela na rezultateTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaUniverza v Ljubljani, Fakulteta za strojništvo