Hydrodynamic forces during the operation of a model radial gate

Abstract

A 1:17 scale physical hydraulic model of a radial gate was employed to determine forces during the lifting and lowering of the gate with rates from 0.1 to 1.1 m/min for prototype (current operating rate is 0.1 m/min), and to determine the combinations of discharge, gate opening and tailwater level that cause instability of the gate. Forces were measured in trunnion bearing and in both hoists without restricting the movement of the model. Tailwater levels covered a wide range, representing the changed conditions after the completion of the downstream dam. The study indicated certain trends regarding the instability of the gate, and showed that the current rate of raising the gates could be significantly increased, providing safer operation of the whole system during some specific operating conditions.

Keywords:

• flume experiments
• hydraulic model
• hydrodynamic forces
• radial gate

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Notes on contributors

Gorazd Novak

Dr Gorazd Novak graduated in 2004 at University of Ljubljana, Faculty of Civil and Geodetic Engineering with a graduation thesis on hydraulic modelling of hydropower structures. He worked as a researcher at the Institute for Hydraulic Research, Ljubljana, from 2004 to 2010, and as an assistant at the Chair of Fluid Mechanics, Faculty of Civil and Geodetic Engineering, University of Ljubljana, from 2010 to 2012. In 2012, he obtained a Ph.D. degree with his doctoral thesis on determination of velocity field of water flow at model side weir using a visualization method. Since then he has been a researcher at the Institute for Hydraulic Research, focusing on physical and numerical (1d and 2d) models and various field measurements. He has authored or co-authored six scientific papers, several other publications and numerous reports of hydraulic studies.

Jure Mlačnik

Jure Mlačnik graduated in 1987 at the Hydraulics Division of the Faculty of Civil and Geodetic Engineering of the University of Ljubljana. He was a researcher and later the manager of the Institute for Hydraulic Research, where he now works as a development associate. His experience covers physical modelling, field measurements, hydrology and hydrographical surveys. He works on numerical modelling and contributed to the introduction of hybrid modelling approach into the Slovenian hydraulic research practice.

Martin Bombač

Dr Martin Bombač graduated in 2005 at the Hydraulics Division of the Faculty of Civil and Geodetic Engineering of the University of Ljubljana with a graduation thesis on hydraulic optimization of the intake part of the runoff-river power plants. He works as a researcher at the Institute for Hydraulic Research, where he focuses on combining mathematical and physical hydraulic modelling. In 2014, he obtained a Ph.D. degree with his doctoral thesis on turbulence models in the PCFLOW2D mathematical model, developed by the Chair of Fluid Mechanics, Faculty of Civil and Geodetic Engineering, University of Ljubljana.

Staša Vošnjak

Staša Vošnjak graduated in 2002 at the Hydraulics Division of the Faculty of Civil and Geodetic Engineering of the University of Ljubljana with the graduation thesis Laboratory measurements of the hydrodynamic parameters for the calibrations of the 2D mathematical models. She works as a researcher at the Institute for Hydraulic Research, where she focuses on mathematical modelling.