hydraulic turbines to be continued by the experimental and analytical approaches on the axial fans pressure side. The complexity of 3-D, non-homogeneous, anisotropic turbulent velocity fields required complex experimental and theoretical approach, associated with the complex numerical procedures. Analytical approaches, complex statistical analyses and experimental methods and afterwards CFD employed in the research are presented in this paper. The 150 scientific papers, numerous diploma works, several master of science (magister) theses, six Ph. D. theses and two in progress, 40 researchers, national and international projects are the facts about the School. Scientific references are chronologically presented. Numerous abstracts from scientific conferences, presentations, projects with industry and lectures are not given here.Many researchers of the School of the turbulent swirling flow at the Faculty of Mechanical Engineering, University of Belgrade (FME UB) carried on and contributed to the research of the turbulent swirling flows . Vušković (1912Vušković ( -2005 published his first paper [1] in 1941, where he studied the problem of generation and stability of the vortex core in turbomachines, specifically behind the hydraulic turbine runners. Vušković continued his research and afterwards published paper [2], and Vušković and Velenšek [4].Obradović [3] discussed vortex hydrodynamic stability with constant circulation in the cylindrical pipes.Determination of the dead water diameter behind the axial fan without guide vanes was done by Protić [5]. Also, he was the first to introduce the idea of investigating the turbulent swirling flow behind the axial fan in the pipe. Further investigations are conducted at the Chair for hydraulic machinery and energy systems and at the Chair for fluid mechanics FME UB.Experimental investigations of the turbulent swirling flow in the long lined straight pipes behind the axial fan without guide vanes started at the FME UB in 1972, when experimental test rig was built and measurement equipment was designed by Benišek. First results from this test rig were published in [6,7,9,13]. Čantrak S. [19] was the first to commence investigations of turbulence at the FME UB and implemented turbulence statistics in the turbulent swirling flow.These investigations are ongoing getting deeper into the turbulent swirling flow phenomenology. The defended theses and published papers are part of this review and are listed in references. Chronologically are presented almost all scientific papers, a number of master of science (magister) theses and six Ph. D. theses that belong to the School. Two Ph. D. theses in this field are in progress. Numerous diploma works were defended at the Chair for hydraulic machinery and energy systems and at the Chair for fluid mechanics FME UB in this field. Forty researchers from Serbia, and from abroad as well, are members of this School. National and international projects, numerous abstracts from scientific conferences, presentations, projects for industry and le...

Numerical flow simulations in a small bulb turbine by the use of Ansys

This paper presents research regarding the influence of turbulent kinetic energy (TKE) level on accuracy of Reynolds averaged Navier-Stokes (RANS) based turbulence models. A theoretical analysis of influence TKE level on accuracy of the RANS turbulence models has been performed according to the Boussinesq hypothesis definition. After that, this theoretical analysis has been investigated by comparison of numerically and experimentally obtained results on the test case of a steady-state incompressible swirl-free flow in a straight conical diffuser named Azad diffuser. Numerical calculations have been performed using the OpenFOAM CFD software and first and secondorder closure turbulence models. TKE level, velocity profiles and Reynolds stresses have been calculated downstream in four different cross sections of the diffuser. Certain conclusions about modeling turbulent flows by − and LRR turbulence models have been made by comparing the velocity profiles, TKE distribution and Reynolds stresses on the selected cross sections.2010 Mathematics Subject Classification: 76F10.