Portrait of Dr László Kollár Dr László Kollár

l.kollar@hud.ac.uk | 01484 473069



Biography

Dr. László E. Kollár received M.Sc. and Ph.D. in Mechanical Engineering from the Budapest University of Technology and Economics, Hungary, and M.Sc. in Mathematics from the University of Texas at Dallas, USA. Formerly, he was an academic at the University of Quebec at Chicoutimi, Canada. In 2012, he joined the School of Computing and Engineering of the University of Huddersfield as a Research Fellow.

Dr. Kollár has been involved in research activities within the broad areas of thermal and fluid sciences as well as dynamics and vibrations. He authored or co-authored more than 50 journal and conference papers and a book chapter. His teaching area includes fluid dynamics, heat transfer and continuum mechanics.

Research and Scholarship

Dr. Kollár’s research interest includes multiphase flows, flow measurement, and nonlinear vibrations. He has been involved in several research projects:

  • Development of an analytical method for reconstruction of velocity profiles using a multi-electrode electromagnetic flow meter
  • Optimal sizing of pipelines transporting multi-sized solid-liquid mixtures
  • Modelling of two-phase air/dispersed water flows considering droplet collision, evaporation and cooling, gravity, and turbulence dispersion; model validation by wind tunnel experiments
  • Variation of ice mass and shape on a cylindrical icing object in a low-speed icing wind tunnel with the angle between wind velocity and axis of cylinder
  • Numerical modeling of conductor vibration and bundle rotation following ice shedding from bundled conductors; model validation by small-scale laboratory experiments and by comparisons to full-scale observations
  • Simulation of wet snow shedding from overhead cables
  • Measurement of stresses developing in cable-ice structures and simulation of ice fracture during wind-induced conductor motion
  • Code development to find poles of retarded differential equations numerically, and to determine the stability of their equilibria; application for a model of the human respiratory control system
  • Modelling of human balancing with time delay on surfaces of unknown inclination
  • Dynamics of digitally controlled unstable piecewise linear systems

Dr. Kollár co-supervised 1 Ph.D. and 2 M.Sc. students, evaluated the research plans and the accomplishments of several graduate students, and reviewed several Ph.D. and M.Sc. theses. He reviewed research papers for AIAA Journal of Thermophysics and Heat Transfer, Cold Regions Science and Technology, IEEE Transactions on Power Delivery, International Journal of Heat and Fluid Flow, Journal of Flow Measurement and Instrumentation, Mathematics and Computers in Simulation, Mathematical Problems in Engineering, and for 4 international conferences.

Publications and Other Research Outputs

Article

Kollar, L., Lucas, G. and Meng, Y. (2015) ‘Reconstruction of velocity profiles in axisymmetric and asymmetric flows using an electromagnetic flow meterMeasurement Science and Technology , 26 (5). ISSN 0957-0233

Kollar, L., Lucas, G. and Zhang, Z. (2014) ‘Proposed method for reconstructing velocity profiles using a multi-electrode electromagnetic flow meterMeasurement Science and Technology , 25 (7), p. 075301. ISSN 0957-0233

Alghadhi, M., Ball, A., Kollar, L., Mishra, R. and Asim, T. (2014) ‘Fuel Consumption Tabulation in Laboratory ConditionsInternational Journal of Recent Development in Engineering and Technology , 2 (4), pp. 29-38. ISSN 2347-6435

Hefny, R., Kollar, L. and Farzaneh, M. (2014) ‘Modeling the influence of periodic loads on snow detachment from suspended cablesCold Regions Science and Technology , 101, pp. 31-39. ISSN 0165232X

Asim, T., Mishra, R., Kollar, L. and Pradhan, S. (2014) ‘Optimal sizing and life-cycle cost modelling of pipelines transporting multi-sized solid-liquid mixturesInternational Journal of Pressure Vessels and Piping , 113, pp. 40-48. ISSN 0308-0161

Kollar, L., Mishra, R. and Asim, T. (2013) ‘Particle size effects on optimal sizing and lifetime of pipelines transporting multi-sized solid-liquid mixturesProcedia CIRP: TESC 2013 - 2nd International Through-life Engineering Services Conference , 11, pp. 317-322. ISSN 2212 - 8271

Banitalebi Dehkordi, H., Farzaneh, M., Van Dyke, P. and Kollar, L. (2013) ‘The effect of droplet size and liquid water content on ice accretion and aerodynamic coefficients of tower legsAtmospheric Research , 132-3, pp. 362-374. ISSN 0169-8095

Kermani, M., Farzaneh, M. and Kollar, L. (2013) ‘The Effects of Wind Induced Conductor Motion on Accreted Atmospheric IceIEEE Transactions on Power Delivery , 28 (2), pp. 540-548. ISSN 0885-8977

Kollar, L., Farzaneh, M. and Van Dyke, P. (2013) ‘Modeling Ice Shedding Propagation on Transmission Lines with or without Interphase SpacersIEEE Transactions on Power Delivery , 28 (1), pp. 261-267. ISSN 0885-8977

Kollar, L. and Farzaneh, M. (2012) ‘Modeling Sudden Ice Shedding from Conductor BundlesIEEE Transactions on Power Delivery , 28 (2), pp. 604-611. ISSN 0885-8977

Asim, T., Mishra, R. and Kollar, L. (2012) ‘Optimisation of a Horizontal Capsule Transporting Pipeline carrying Cylindrical CapsulesJournal of Physics: Conference Series , 364 (1), p. 012071. ISSN 1742-6596

Hefny, R., Kollar, L. and Farzaneh, M. (2012) ‘Simulation of Snow Adhesion on Real-Scale LinesInternational Journal of Mechanical Engineering and Mechatronics , 1 (1), pp. 102-108. ISSN 1929-2724

Farzaneh, M., Hefny, R. and Kollar, L. (2012) ‘Experimental Investigation of Dynamic Force on The Performance of Wet Snow SheddingInternational Journal of Mechanical Engineering and Mechatronics , 1 (1), pp. 72-79. ISSN 1929-2724

Kermani, M., Farzaneh, M. and Kollar, L. (2010) ‘Estimation of stresses in atmospheric ice during aeolian vibration of power transmission linesJournal of Wind Engineering and Industrial Aerodynamics , 98 (10-11), pp. 592-599. ISSN 0167-6105

Kollar, L. and Farzaneh, M. (2010) ‘Wind-tunnel investigation of icing of an inclined cylinderInternational Journal of Heat and Mass Transfer , 53 (5-6), pp. 849-861. ISSN 0017-9310

Kollar, L., Olqma, O. and Farzaneh, M. (2010) ‘Natural wet-snow shedding from overhead cablesCold Regions Science and Technology , 60 (1), pp. 40-50. ISSN 0165-232X

Kollar, L. and Farzaneh, M. (2009) ‘Modeling the dynamic effects of ice shedding on spacer dampersCold Regions Science and Technology , 57 (2-3), pp. 91-98. ISSN 0165-232X

Kollar, L. and Farzaneh, M. (2009) ‘Spray characteristics of artificial aerosol clouds in a low-speed icing wind tunnelAtomization and Sprays , 19 (4), pp. 387-405. ISSN 1046-5111

Kollar, L. and Farzaneh, M. (2008) ‘Vibration of Bundled Conductors Following Ice SheddingIEEE Transactions on Power Delivery , 23 (2), pp. 1097-1104. ISSN 0885-8977

Kollar, L. and Farzaneh, M. (2007) ‘Modeling the evolution of droplet size distribution in two-phase flowsInternational Journal of Multiphase Flow , 33 (11), pp. 1255-1270. ISSN 0301-9322

Karev, A., Farzaneh, M. and Kollar, L. (2007) ‘Measuring temperature of the ice surface during its formation by using infrared instrumentationInternational Journal of Heat and Mass Transfer , 50 (3-4), pp. 566-579. ISSN 0017-9310

Kollar, L., Farzaneh, M. and Karev, A. (2006) ‘Modeling droplet size distribution near a nozzle outlet in an icing wind tunnelAtomization and Sprays , 16 (6), pp. 673-686. ISSN 1045-5110

Kollar, L., Farzaneh, M. and Karev, A. (2005) ‘Modeling droplet collision and coalescence in an icing wind tunnel and the influence of these processes on droplet size distributionInternational Journal of Multiphase Flow , 31 (1), pp. 69-92. ISSN 0301-9322

Kollar, L. and Turi, J. (2005) ‘Numerical Stability Analysis in Respiratory Control System ModelsElectronic Journal of Differential Equations: Proceedings of 2004 Conference on Differential Equations and Applications in Mathematical Biology , 12, pp. 65-78.

Kollar, L., Stepan, G. and Turi, J. (2004) ‘Dynamics of piecewise linear discontinuous mapsInternational Journal of Bifurcation and Chaos , 14 (07), pp. 2341-2351. ISSN 0218-1274

Kollar, L., Stepan, G. and Turi, J. (2003) ‘Dynamics of delayed piecewise linear systemsElectronic Journal of Differential Equations: Fifth Mississippi State Conference on Differential Equations and Computational Simulations , 10, pp. 163-185.

Kollar, L., Stepan, G. and Turi, J. (2002) ‘Digital balancing of systems with backlashDecision and Control, 2002, Proceedings of the 41st IEEE Conference on , 3, pp. 3106-3111. ISSN 0191-2216

Kollar, L., Somlo, J. and Stepan, G. (2000) ‘Szabályozott egyensúlyozási rendszer periodikus megoldásai [Periodic Responses of a Controlled Balancing System]Gépgyártástechnológia, (10). ISSN 0016-8580

Stepan, G. and Kollar, L. (2000) ‘Balancing with reflex delayMathematical and Computer Modelling , 31 (4-5), pp. 199-205. ISSN 0895-7177

Kollar, L., Stepan, G. and Hogan, S. (2000) ‘Sampling Delay and Backlash in Balancing SystemsPeriodica Polytechnica Mechanical Engineering , 44 (1), pp. 77-84. ISSN 0324-6051

Book Section

Kollar, L., Lucas, G. and Zhang, Z. (2013) ‘An Analytical Method for Reconstruction of Velocity Profiles using a Multi-Electrode Electromagnetic Flow Meter’. In: 7th World Congress on Industrial Process Tomography. Krakow, Poland: International Society for Industrial Process Tomography. pp. 385-394. ISBN 978 0 853 16323 7

Kollar, L. and Farzaneh, M. (2011) ‘Modeling and Experimental Study of Variation of Droplet Cloud Characteristics in a Low-Speed Horizontal Icing Wind Tunnel’. In: Wind Tunnels: Aerodynamics, Models and Experiments. : Nova Publishers. pp. 93-128. ISBN 978-1-61209-204-1

Kollar, L. and Stepan, G. (2000) ‘Digital controlling of piecewise linear systems’. In: 2000 2nd International Conference. Control of Oscillations and Chaos. Proceedings (Cat. No.00TH8521). : IEEE. pp. 327-330. ISBN 0-7803-6434-1

Kollar, L. and Stepan, G. (1999) ‘Digital balancing using artificial labyrinth’. In: Proceedings of the 5th Conference on Dynamical Systems - Theory and Applications. : Technical University Press. pp. 221-225.

St�p�n, G. and Kollar, L. (1999) ‘Robotic balancing using artificial labyrinth’. In: Romansy 12: Theory And Practice Of Robots And Manipulators. : Springer. pp. 443-450. ISBN 9783211831434

Conference Item

Kollar, L., Mishra, R. and Jain, A. (2016) ‘Inverse Design of Blade Shapes for Vertical Axis Wind Turbines’. In: 6th International and 43rd National Conference on Fluid Mechanics and Fluid Power December 15-17, 2016,, December 15-17, 2016,, MNNIT Allahaabd, India

Kollar, L., Lucas, G. and Zhang, Z. (2013) ‘An analytical method for reconstruction of velocity profiles using a multi-electrode electromagnetic flow meter’. In: 7th World Congress on Industrial Process Tomography, 2nd - 5th September 2013, Krakow, Poland

Hefny, R., Farzaneh, M. and Kollar, L. (2012) ‘Simulation of Snow Adhesion on Power Transmission Cables’. In: International Conference on Mechanical Engineering and Mechatronics, 16th - 18th August 2012, Ottowa, Canada

Hefny, R., Kollar, L. and Farzaneh, M. (2012) ‘Influence of Dynamic Forces on Wet Snow Shedding from Overhead Cables’. In: International Conference on Mechanical Engineering and Mechatronics, 16th - 18th August 2012, Ottowa, Canada

Kollar, L. and Farzaneh, M. (2012) ‘Influence of transmission line parameters on high-amplitude vibration of conductor bundles’. In: 10th world congress on computational mechanics, 8-13th July 2012, Sao Paulo, Brazil

Kulyakhtin, A., Kollar, L., L�set, S. and Farzaneh, M. (2012) ‘Numerical Simulations of 3D Spray Flow in a Wind Tunnel with Application of O’Rourke’s Interaction Algorithm and Its Validation’. In: 21st International Symposium on Ice, 11th - 15th June 2012, Dalian, China

Kulyakhtin, A., L�set, S. and Kollar, L. (2012) ‘Small-Scale Simulation of Seawater Icing in Natural Field Conditions’. In: 21st International Symposium on Ice, 11th - 15th June 2012, Dalian, China

Kollar, L. and Farzaneh, M. (2011) ‘Numerical modeling and small-scale experimental simulation of ice shedding propagation on bundled conductors’. In: IWAIS 2011 - The 14th International Workshop on Atmospheric Icing of Structures, 8-13th May 2011, Chongqing, China

Kollar, L., Farzaneh, M. and Van Dyke, P. (2011) ‘Modeling of cable vibration following ice shedding propagation’. In: IWAIS 2011 - The 14th International Workshop on Atmospheric Icing of Structures, 8-13th May 2011, Chongqing, China

Banitalebi Dehkordi, H., Farzaneh, M., Kollar, L. and Van Dyke, P. (2011) ‘Experimental study of spray characteristics and its uniformity under different icing conditions’. In: IWAIS 2011 - The 14th International Workshop on Atmospheric Icing of Structures, 8-13th May 2011, Chongqing, China

Hefny, R., Kollar, L., Farzaneh, M. and Payrard, C. (2009) ‘Adhesion of Wet Snow to Different Cable Surfaces’. In: 13th International Workshop on Atmospheric Icing of Structures, 8th - 11th September 2009, Andermatt, Switzerland

Fony�, A., Kollar, L., Farzaneh, M. and Montpellier, P. (2009) ‘Experimental Simulation of Wet-Snow Shedding from Sagged Cables’. In: 13th International Workshop on Atmospheric Icing of Structures, 8th - 11th September 2009, Andermatt, Switzerland

Olqma, O., Kollar, L., Farzaneh, M. and Pellet, L. (2009) ‘Modeling Wet-Snow Shedding from Current-Carrying Conductors’. In: 13th International Workshop on Atmospheric Icing of Structures, 8th - 11th September 2009, Andermatt, Switzerland

Kollar, L. and Farzaneh, M. (2007) ‘Dynamic model for spacers on triple and quad bundles of conductors’. In: 7th International symposium on cable dynamics, 2007, Vienna, Austria

Kollar, L. and Farzaneh, M. (2006) ‘Dynamic Behavior of Cable Systems with Spacers Following Ice Shedding’. In: ICNPAA-2006: Mathematical Problems in Engineering and Aerospace Sciences, 21st - 23rd June 2006, Budapest, Hungary

Kalman, T., Farzaneh, M., Kollar, L., McClure, G. and Leblond, A. (2005) ‘Dynamic behavior of iced overhead cables subjected to mechanical shocks’. In: 6th International Symposium on Cable Dynamics, 2005, Charleston, South Carolina, USA

Kollar, L. and Farzaneh, M. (2005) ‘Dynamic analysis of overhead cable vibrations as a result of ice shedding’. In: 6th International Symposium on Cable Dynamics, 2005, Charleston, South Carolina, USA

Lozowski, E., Oleskiw, M., Blackmore, R., Karev, A., Kollar, L. and Farzaneh, M. (2005) ‘Spongy Icing Revisited: Measurements of Ice Accretion Liquid Fraction in Two Icing Tunnels’. In: 43rd AIAA Aerospace Sciences Meeting and Exhibit, 10th - 13th January 2005, Reno, Nevada, USA

Karev, A., Farzaneh, M., Kollar, L. and Vaslon, S. (2004) ‘New dynamic aspects of contemporaneous concepts in atmospheric icing modelling’. In: 17th International Symposium on Ice, 2004, St Petersburg, Russia

Karev, A., Farzaneh, M., Kollar, L. and Vaslon, S. (2004) ‘Freezing of water in an open channel flow under supercooled ambient conditions - preliminary results’. In: 17th International Symposium on Ice, 2004, St Petersburg, Russia

Kollar, L., St�p�n, G. and Turi, J. (2004) ‘Dynamics of sampled systems with backlash’. In: 11th world congress in mechanism and machine science, 1-4th April 2004, Tianjin University, Tianjin, China

Kollar, L., Somlo, J. and St�p�n, G. (2000) ‘Periodic responses of a controlled balancing system’. In: VIIIth international conference on the theory of machines and mechanisms, 5-7th September 2000, Technical University of Liberec, Czech republic

Kollar, L. and Stepan, G. (2000) ‘Balancing on inclined surface’. In: 2nd Conference on Mechanical Engineering, 2000, Budapest, Hungary

Kollar, L., Stepan, G. and Hogan, S. (2000) ‘Backlash in balancing systems using approximate spring characteristics’. In: 3rd European Nonlinear Oscillations Conference, 8-12 August 1999, Lyngby, Denmark

Kollar, L (1998) ‘Backlash in machines stabilized by control force’. In: 1st Conference on Mechanical Engineering, 1998, Budapest, Hungary

Monograph

Farzaneh, M., Jakl, F., Arabani, M., Eliasson, A., Fikke, S., Gallego, A., Haldar, A., Isozaki, M., Lake, R., Leblond, L., McDougall, G., Minchin, M., Mito, M., Pellet, L., Ronzio, D., Santana Lopez, J., Ryerson, C., Shkaptsov, V., Turbin, S., Wareing, B., Zangl, H., Anderson, B., Kermani, M., Kollar, L., Menini, R., Peter, Z. and Volat, C. (2010) Systems for prediction and monitoring of ice shedding, anti-icing and de-icing for power line conductors and ground wires CIGRE

Banitalebi Dehkordi, H., Kollar, L., Farzaneh, M., Camirand, P. and D'Amours, C. (2010) Introduction, instrumentation and calibration of CIGELE atmospheric icing research wind tunnel University of Quebec (Unpublished)

Research Degree Supervision

General projects areas

  • Design of wind turbine blade shapes considering ice accretion
  • Wind turbine blade vibration due to uneven load
  • Reconstruction of velocity profiles using a multi-electrode electromagnetic flow meter
  • Modelling particle collision and the evolution of particle size distribution in two-phase flows

Current opportunities

  • Please contact this member of staff to discuss possible opportunities.