Location: Reactor Engineering Division - R4 > Staff > Ivo Kljenak {en} Si

Dr. Ivo Kljenak
Research Associate
Reactor Engineering Division
Jozef Stefan Institute
Jamova cesta 39

SI-1000 Ljubljana

Phone: (+386) 1 5885 332
Fax: (+386) 1 5885 377
Email: ivo.kljenak@ijs.si

More about the Institute
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More about physicist Jozef Stefan


Biographical sketch

Born in 1961 in Moscow (Russia).
Spent childhood in Sofia (Bulgaria), Tunis (Tunisia) and Belgrade (Yugoslavia) and adolescence in Paris (France).
Since 1980 lives in Ljubljana.

Current research interests

Dispersed gas-liquid two-phase flow
  • Subcooled nucleate boiling flow
  • Transition from bubbly to slug flow in vertical channels
Severe accidents in nuclear power plants
  • Atmosphere mixing and stratification in containment (experiments TOSQAN, MISTRA, THAI and PANDA)
  • Hydrogen combustion in containment (experiments ENACCEF and THAI)
  • Simulation of severe accidents with system codes (ASTEC and CONTAIN)
Modelling of gas flow in nanotubes

Current participation in international projects

7th EU FP Severe Accident Research Network of Excellence (SARNET)
OECD SETH-2: experiments on atmosphere mixing in MISTRA and PANDA facilities
OECD International Standard Problem No.49 "Hydrogen combustion"
PHEBUS Circuit and Containment Aerosol Interpretation Circle


Alma mater : Faculty of Mechanical Engineering, University of Ljubljana
    B.Sc. (1984), M.Sc. (1988), Ph.D. (1992)
High school : Lycee J-B Say Paris, France


Since 1995 at Jozef Stefan Institute
From 1984 to 1994 research and teaching assistant at Faculty of Mechanical Engineering, University of Ljubljana

Other interests

Travelling (especially in the East)
Reading (Marques, Gide, Proust, Rushdie, gave up Joyce)
Sixties' and early seventies' rock music
Marathon running Ljubljana 2007  Radenci 2008  Ljubljana 2008  Radenci 2009  Logarska 2009

Selected journal papers

M.Babić, I.Kljenak, B.Mavko, 2009, Simulations of TOSQAN Containment Spray Tests with Combined Eulerian CFD and Droplet-Tracking Modelling, Nuclear Engineering and Design, vol.239, pp.708-721.

M.Babić, I.Kljenak, B.Mavko, 2008, Prediction of Light Gas Distribution in Experimental Containment Facilities using the CFX4 Code, Nuclear Engineering and Design, vol.238, pp.538-550.

I.Kljenak, M.Babić, B.Mavko, I.Bajsić, 2006, Modeling of Containment Atmosphere Mixing and Stratification Experiment using a CFD Approach, Nuclear Engineering and Design, vol.236, pp.1682-1692.

I.Kljenak, B.Mavko, 2006, Simulation of Void Fraction Profile Evolution in Subcooled Nucleate Boiling Flow in a Vertical Annulus Using a Bubble-Tracking Approach, Heat and Mass Transfer, vol.42, pp.552-561.

B.Končar, I.Kljenak, B.Mavko, 2004, Modelling of Local Two-Phase Flow Parameters in Upward Subcooled Flow Boiling at Low Pressure, International Journal of Heat and Mass Transfer, vol.47, pp.1499-1513.

R.Jordan Cizelj, B.Mavko, I.Kljenak, 2001, Component Reliability Assessment Using Quantitative and Qualitative Data, Reliability Engineering and System Safety, vol.71, pp.81-95.

A.Horvat, I.Kljenak, J.Marn, 2001, Two-Dimensional Large-Eddy Simulation of Turbulent Natural Convection due to Internal Heat Generation, International Journal of Heat and Mass Transfer, vol.44, pp.3985-3995.

I.Žun, I.Kljenak, S.Može, 1993, Space-Time Evolution of the Nonhomogeneous Bubble Distribution in Upward Flow, International Journal of Multiphase Flow, vol.19, pp.151-172.

Jozef Stefan Institute, Reactor Engineering Division (R4), Jamova cesta 39, SI-1000 Ljubljana, Slovenia
Phone: (+386) 1 588 54 50, Fax: (+386) 1 588 53 77