U radu je dan opis pojave oscilacija vodnih masa na sustavu akumulacija - dovodni cjevovod – vodna komora, kao i opis pojave hidrauličkog udara koja nastaje uslijed naglog zatvaranja zatvarača na danom sustavu. U svrhu dobivanja mjerodavne hidrodinamičke analize oscilacija vodnih masa u cilindričnoj vodnoj komori provedena su eksperimentalna mjerenja na fizikalnom modelu GUNT HM156 koji predstavlja sastavni dio mjernog instrumentarija hidrotehničkog laboratorija Građevinskog fakulteta Sveučilišta u Rijeci. Hidrodinamička analiza je provedena na temelju više eksperimentalnih pokusa u kojima su kao ulazne vrijednosti uzete promjenjiva razina gornje vode u akumulaciji te različiti dotok vode (protok) u cilindričnu vodnu komoru koji je reguliran putem kuglastog ventila. Hidrodinamička analiza se bazira na dva odvojena dijela. U prvom dijelu je razmatrana isključivo promjena oscilacija vodnih masa u vodnoj komori kod naglog zatvaranja solenoidnog ventila, dok je drugi dio analize vezan za pojavu hidrauličkog udara i definiranje brzine širenja tlačnih poremećaja u vodi. Za potrebe istraživanja na fizikalnom modelu korištena je sofisticirana mjerna tehnika kao i primjena osciloskopa. This paper presents a description of the water mass oscillation on the accumulation system – inlet pipe - water chamber, as well as a description of the occurrence of a water hammer due to the sudden closure of the shutter on a given system. For the purpose of obtaining the relevant hydrodynamic analysis of the water mass oscillation in the cylindrical water chamber, experimental measurements were carried out on the physical model GUNT HM156, which is an integral part of the measuring instrument of the hydro technical laboratory of the Faculty of Civil Engineering of the University of Rijeka. The hydrodynamic analysis was carried out based on more experimental trials, in which the input water values were the changeable upper water level in the accumulation and the different water influx (flow) in the cylindrical water chamber regulated by the ball valve. The hydrodynamic analysis is based on two separate parts. In the first part, only the water mass oscillation in the water chamber at the sudden closing of the solenoid valve has been considered, while the second part of the analysis is related to the occurrence of a water hammer, and the defining of the velocity propagation of pressure disorders in the water. For the purposes of the research on the physical model, sophisticated measurement technique as well as the oscilloscope were used.