Blömeling, FrankFrankBlömelingRichter, SteffenSteffenRichterSchlüter, MichaelMichaelSchlüter2021-10-082021-10-082015International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015. - Red Hook, NY. - Vol. 3 (2015): pp. 2020-2033 (2015)http://hdl.handle.net/11420/10481In many industrial applications, e.g. the emergency core cooling in nuclear power plants, the reliable operation of pumps is an indispensable requirement which can only be guaranteed when gas entrainment into the pumps is avoided. One of the main sources of gas entrainment are surface vortices which may develop at surfaces between a liquid and a gas if the liquid level is below a critical submergence of the pump intake. Thus, the determination of the critical submergence is a safety relevant matter for the design of pump intakes. Therefore, a test facility was built at the Hamburg University of Technology which provides experimental data on the shape of surface vortices in vertical vessels and strongly rotating flow. In this paper CFD results are presented concerning these experiments. The CFD simulations include a single phase approach as well as free surface simulations. To obtain the surface deformation in the single phase case the corresponding simulations are combined with an analytical vortex model whose applicability is discussed. The results from the single phase and the free surface simulations are then compared with each other and the experiment in order to assess the efficiency of the different strategies to compute the shape of surface vortices.enBurgers-rott modelCFD simulationsNecessary submergenceSurface deformationSurface vorticesPhysikTechnikIngenieurwissenschaftenConference PaperOther