{"?xml":{"@version":"1.0"},"edm:RDF":{"@xmlns:dc":"http://purl.org/dc/elements/1.1/","@xmlns:edm":"http://www.europeana.eu/schemas/edm/","@xmlns:wgs84_pos":"http://www.w3.org/2003/01/geo/wgs84_pos","@xmlns:foaf":"http://xmlns.com/foaf/0.1/","@xmlns:rdaGr2":"http://rdvocab.info/ElementsGr2","@xmlns:oai":"http://www.openarchives.org/OAI/2.0/","@xmlns:owl":"http://www.w3.org/2002/07/owl#","@xmlns:rdf":"http://www.w3.org/1999/02/22-rdf-syntax-ns#","@xmlns:ore":"http://www.openarchives.org/ore/terms/","@xmlns:skos":"http://www.w3.org/2004/02/skos/core#","@xmlns:dcterms":"http://purl.org/dc/terms/","edm:WebResource":[{"@rdf:about":"http://www.dlib.si/stream/URN:NBN:SI:DOC-YOMNRSPJ/74829f6f-70c8-4c31-8a32-98972b2fca2d/PDF","dcterms:extent":"5303 KB"},{"@rdf:about":"http://www.dlib.si/stream/URN:NBN:SI:DOC-YOMNRSPJ/f658a76f-af7e-4999-bdfc-ba6b5997d253/TEXT","dcterms:extent":"42 KB"}],"edm:TimeSpan":{"@rdf:about":"1999-2025","edm:begin":{"@xml:lang":"en","#text":"1999"},"edm:end":{"@xml:lang":"en","#text":"2025"}},"edm:ProvidedCHO":{"@rdf:about":"URN:NBN:SI:DOC-YOMNRSPJ","dcterms:isPartOf":[{"@rdf:resource":"https://www.dlib.si/details/URN:NBN:SI:spr-6QOUKQ9A"},{"@xml:lang":"sl","#text":"Strojniški vestnik"}],"dcterms:issued":"2014","dc:creator":["Bergant, Anton","Bulatović, Vladimir","Karadžić, Uroš"],"dc:format":[{"@xml:lang":"sl","#text":"številka:11"},{"@xml:lang":"sl","#text":"letnik:60"},{"@xml:lang":"sl","#text":"str. 742-754, SI 139"}],"dc:identifier":["ISSN:0039-2480","COBISSID:13773595","URN:URN:NBN:SI:doc-YOMNRSPJ"],"dc:language":"en","dc:publisher":{"@xml:lang":"sl","#text":"Zveza strojnih inženirjev in tehnikov Slovenije et al."},"dc:subject":[{"@xml:lang":"sl","#text":"cevni sistemi"},{"@xml:lang":"sl","#text":"neustaljeno stensko trenje"},{"@xml:lang":"sl","#text":"preizkusna postaja"},{"@xml:lang":"sl","#text":"prekinitev kapljevinskega stebra"},{"@xml:lang":"sl","#text":"ventili"},{"@xml:lang":"sl","#text":"vodni udar"}],"dcterms:temporal":{"@rdf:resource":"1999-2025"},"dc:title":{"@xml:lang":"sl","#text":"Valve-induced water hammer and column separation in a pipeline apparatus|"},"dc:description":[{"@xml:lang":"sl","#text":"A flexible experimental apparatus for investigating water hammer and column separation in an unsteady friction-dominated pipelines has been developed and designed. The apparatus has been tested for steady and unsteady flow conditions. Transient cavitation and column separation phenomena have been observed in a number of experimental runs. Water hammer has been triggered by both the closing and opening of electro-pneumatic (EV) and hand-operated (HV) valves. The experimental data have been compared with results given from in-house numerical code written in Visual Fortran based on the method of the characteristics (MOC) with a convolution-based unsteady friction model (CBM) included. The column separation and transient cavitation phenomena are modelled via a discrete gas cavity model (DGCM). There is good agreement between the experimental and numerical results; the model is robust and, therefore, it is recommended for engineering practice. In addition, the influence of variations of the pressure wave speed and the uncertainty in flow rate measured by the electromagnetic flow meter are also investigated"},{"@xml:lang":"sl","#text":"Članek obravnava vodni udar in pretrganje kapljevinskega stebra inducirana z ventilom v preizkusni postaji postavljeni v laboratoriju Univerze Črne gore, Podgorica. Glavni cilj raziskave je bil verifikacija in validacija diskretnega plinskega kavitacijskega modela z upoštevanjem nestalnega kapljevinskega trenja za različne pretočne pogoje. Osnove modela so bile postavljene v SV-JME v letu 2005. Model bazira na enčbah neustaljenega kapljevinskega toka v ceveh. Transformacija postavljenih parcialnih diferencialnih enačb hiperboličnega tipa z uporabo metode karakteristik tvori osnovo algoritma za vodni udar. V deltoidno mrežo metode karakteristik je vgrajen kovolucijski model neustaljenega stenskega trenja z uporabo zmogljivih računalniških orodij. Vgradnja plinskih kavitacij v numerična vozlišča da diskretni plinski kavitacijski model. Eksperimentalna postaja je sestavljena iz horizontalnega cevovoda, ki je vgrajen med gorvodni tlačni kotel in dolvodni ventil z iztokom v atmosfero. Dolžina jeklenega cevovoda je 54,23 m, notranji premer je 18 mm, debelina stene cevi 2 mm. Tlačne spremembe zasledujemo s pomočjo štirih hitro odzivnih zaznaval, ki so vgrajeni vzdolž cevovoda. Prehodni pojav je induciran z zapiranjem ali odpiranjem kroglastega zasuna dolvodno, vzdolž cevi in gorvodno. Na ta način lahko raziskujemo prehode v cevovodih različnih dolžin"}],"edm:type":"TEXT","dc:type":[{"@xml:lang":"sl","#text":"znanstveno časopisje"},{"@xml:lang":"en","#text":"journals"},{"@rdf:resource":"http://www.wikidata.org/entity/Q361785"}]},"ore:Aggregation":{"@rdf:about":"http://www.dlib.si/?URN=URN:NBN:SI:DOC-YOMNRSPJ","edm:aggregatedCHO":{"@rdf:resource":"URN:NBN:SI:DOC-YOMNRSPJ"},"edm:isShownBy":{"@rdf:resource":"http://www.dlib.si/stream/URN:NBN:SI:DOC-YOMNRSPJ/74829f6f-70c8-4c31-8a32-98972b2fca2d/PDF"},"edm:rights":{"@rdf:resource":"http://rightsstatements.org/vocab/InC/1.0/"},"edm:provider":"Slovenian National E-content Aggregator","edm:intermediateProvider":{"@xml:lang":"en","#text":"National and University Library of Slovenia"},"edm:dataProvider":{"@xml:lang":"sl","#text":"Univerza v Ljubljani, Fakulteta za strojništvo"},"edm:object":{"@rdf:resource":"http://www.dlib.si/streamdb/URN:NBN:SI:DOC-YOMNRSPJ/maxi/edm"},"edm:isShownAt":{"@rdf:resource":"http://www.dlib.si/details/URN:NBN:SI:DOC-YOMNRSPJ"}}}}