Dr. Pavlos Stephanou
Cyprus University of Technology
A major theme of our research work is the development of reliable constitutive models for describing the dynamics and flow behavior of complex polymeric fluids. To this, we rely on the use of non-equilibrium thermodynamics (NET), in particular on the Generalized Bracket and GENERIC formalisms, for developing closed-form balance equations for the fundamental hydrodynamic fields. No matter what the system is (say biological or chemical), it must obey the laws of thermodynamics. In particular, when the system is beyond equilibrium (e.g., under the influence of a flow field), its time evolution must be dictated by the laws of non-equilibrium thermodynamics (NET). This is exactly the reason why in our work we employ NET: by construction the new constitutive models obey the laws of thermodynamics. So far, we have developed generalized constitutive models for polymer melts, polymer solutions, and polymer nanocomposites. Currently, we are using NET to develop constitutive models for biomolecular fluids such as blood.
In most cases, the resulting constitutive equations contain parameters whose values are not known. To overcome this, we resort to atomistic simulations, both (equilibrium) Molecular Dynamics (MD) and non-equilibrium MD (NEMD), and coarse-grained Brownian Dynamics (BD) simulations. This allows us to develop interconnections between three different levels of system description: the atomistic or microscopic, the mesoscopic, and the macroscopic. As one moves from the atomistic to the macroscopic level (coarse-graining), the degrees of freedom of the system are significantly reduced, which results in dramatic reductions in computational demands. However, coarse-graining must be done carefully to avoid the loss of important information. Our work connects the three levels through the development of scale-bridging methodologies, and the outcome is a set of, closed-form, constitutive equations for the time evolution of the structural and hydrodynamic fields selected to describe the system. Overall, the building blocks of our bridging methodology are the following: 1) At the atomistic level: we use atomistic MD and NEMD simulations to simulate the real system to obtain the values of important parameters entering the description of the system at the mesoscopic level. 2) At the mesoscopic level: we design coarse-grained simulations (e.g. BD simulations) which provide information about the evolution of the system for much larger time spans than what is addressed by atomistic simulations. 3)At the macroscopic level: we use NET to derive generalized constitutive models for complex systems whose parameters are evaluated from the previous levels.
- 2011: Ph.D., Department of Chemical Engineering, University of Patras
- 2006: Diploma in Chemical Engineering, University of Patras
- 09/2019 – present: Assistant Professor, Department of Chemical Engineering, Cyprus University of Technology, Limassol, Cyprus.
- 08/2018– 07/2019: Post-doctoral research fellow, Novamechanics Ltd, Nicosia, Cyprus (by receiving the research grant POST-DOC/0916/0197).
- 09/2016 – 07/2018: Post-doctoral research fellow, Department of Mathematics and Statistics, University of Cyprus, Cyprus (with Prof. Georgios Georgiou).
- 03/2015-09/2016: Post-doctoral research fellow, Department of Materials, ETH-Zürich, Institut für Polymere, Zürich, Switzerland (with Profs. Hans Christian Öttinger and Martin Kröger).
- 09/2011-02/2015: Post-doctoral research fellow, Department of Mathematics and Statistics, University of Cyprus, Cyprus (with Prof. Georgios Georgiou).
- 09/2008-04/2009: Ph.D. Research Assistant, Department of Chemical and Biomolecular Engineering, The University of Tennessee-Knoxville, TN, USA (with Profs. Brian J. Edwards and Bamin Khomami).
- 09/2006-07/2011: PhD studies, thesis ” Development of scale-bridging methodologies and algorithms founded on the outcome of detailed atomistic simulations for the reliable prediction of the viscoelastic properties of polymer melts”, supervised by Prof. Vlasis G. Mavrantzas.
- Top of Class Award for Undergraduate studies, State Scholarship Foundation, annually 2001 – 2006.
- Top of Class Award for Undergraduate studies for the academic year 2003-2004, Technical Chamber of Greece, 2007.
- Top of Class Award for excellence in Undergraduate studies, Technical Chamber of Greece, 2008.
- Marie Curie Reintegration grant, European Commission, (FP7-PEOPLE-2011-CIG, Code 293945), 08/2011-07/2012 [Terminated as it was not possible to have it funded simultaneously with ΔΙΔΑΚΤΩΡ/0311/40].
- National post-doctoral grant, Cyprus Research Promotion Foundation (ΔΙΔΑΚΤΩΡ/0311/40), 07/2012-12/2014.
- Swiss Government Excellence Scholarship for Foreign Scholars, 01/09/2015-31/08/2016 (ESKAS No. 2015.0297).
- Cyprus Research Award – “Young Researcher” 2015 (Thematic Area: Physical Sciences and Engineering), November 2015, https://www.youtube.com/watch?v=SX1OC-xs9zA (in Greek).
- National grant, Cyprus Research Promotion Foundation (made available through the Cyprus Research Award – “Young Researcher” 2015) (ΚΟΥΛΤΟΥΡΑ/ΒΡ-ΝΕ/0415/01), 09/2016-03/2018.
- Member of Hellenic Society of Rheology (HSR), European Society of Rheology (ESR), and Society of Rheology (SOR).
- Reviewer for Physical Review Letters (PRL), Langmuir, Soft Matter, Journal of Rheology, Journal of Chemical Physics, Industrial and Engineering Chemistry Research, Powder Technology, Chemical Physics Letters, Physical Review E, Journal of Non-Newtonian Fluid Mechanics, and Macromolecular Theory and Simulation.
Dr. Loukas Peristeras
Dr. Loukas Peristeras is a Researcher in the Molecular Thermodynamics and Modelling of Materials Laboratory (MTMML) at the National Center for Scientific Research “Demokritos” in Athens, Greece. He has worked as senior research scientist in a scientific software high-tech company (Sienomics SARL) from 2006 to 2014 where he was in charge of the development of various tools integrated in the main software solution of the company. In parallel, he was responsible for the preparation and submission of research proposals for funding. He is the creator of “Amorphous Builder”, a software for the creation of initial configuration for molecular modeling, integrated in MAPS® commercial software and he has contributed to the development of open source scientific projects (LAMMPS, MCCCS, TOWHEE). His main scientific interest is the application of available schemes, their improvement and the development and new approaches for the calculation of material properties by means of molecular and thermodynamic modeling.
- 2003: Ph.D., Department of Chemistry, National and Kapodistrian University of Athens
- 2000: Master’s Degree in Polymer Science, National and Kapodistrian University of Athens
- 1996: Diploma in Chemical Engineering, National Technical University of Athens
- 2015 – present: Research Scientist, National Center for Scientific Research “Demokritos”, Institute of Nanoscience and Nanotechnology
- 2006 – 2014: Senior Research Scientist, Scienomics SARL, France
- 2003 – 2015: Postdoctoral researcher, Computational Materials Science and Engineering group (COMSE), National Technical University of Athens
- Reviewer for: Physical Chemistry Chemical Physics (PCCP), European Polymer Journal
Dr. Nikolaos Lempesis
Mathematical, computational and multiscale simulation sciences that translate to the cutting edge of materials research. Developing and delivering theoretical frameworks that describe the underlying structure-property-function relationships to advance novel scientific endeavors. Facilitating the fusion of theory and experimentation by intelligent and intuitive software technologies.
- 2013: Ph.D., School of Chemical Engineering, National Technical University of Athens (NTUA)
- 2007: Diploma in Chemical Engineering, Biotechnology and Process Engineering, Technical University of Munich (TUM)
- 2007: Diploma in Chemical Engineering, Materials Science, NTUA
- 2017 – present: Post-doctoral research associate, Department of Mechanical Engineering, Swiss Federal Institute of Technology (ETH)
- 2013 – 2016: Post-doctoral research associate, Department of Chemical Engineering, Massachusetts Institute of Technology (MIT)
- 2008-2013: PhD thesis “Molecular simulation of glass forming materials”, supervised by Prof. Doros N. Theodorou at NTUA
- Award from the Technical Chamber of Greece (Τ.Ε.Ε.) for academic achievements at NTUA (2012)
- HPC-Europa2 Transnational Access program fellowship to visit GENCI-CINES (Oct 1, 2011 – Dec 31, 2011) in Paris-Montpellier/France, (2011)
- “NTUA Thomaidion award” 2010 for scientific publication on peer-reviewed journals, (2010)
- National Strategic Reference Framework (NSRF), Enhancement of research man power through the implementation of thesis – HERACLITUS ΙΙ/ Hellenic Ministry of National Education and Religious Affairs: PhD
- Scholarship (Sep 1, 2010 – Aug 31, 2013) for the project entitled “Molecular simulations of glass forming materials”, (2010)
- Silver medal “Prometheus Pyrforos”, emblem of NTUA, for graduating second in rank, Magna Cum Laude, (2008)
- Scholarship of the Department of Materials Science and Engineering of the NTUA, (2007, 2008, 2009)
- Scholarship of the Bodossakis Foundation, (2008)
- Scholarship and award for the academic years 2000,2001 and 2003 offered by the National Scholarship Foundation of Greece (Ι.Κ.Υ.) for the best effort during the first three academic years at NTUA (2008)
- EU Scholarship for the participation to the T.I.M.E. Double Degree Program, (2003, 2004)
Kefalogianni award for academic achievements at the NTUA (2000, 2001, 2003)
- Reviewer at Soft Matter, Polymer, Macromolecules, JPC, JCP, Sensors
- Member of the Top Industrial Managers of Europe (T.I.M.E.) association
- Member of the: American Chemical Society (ACS), American Institute of Chemical Engineers (AIChE)
- Expert in: Wolfram Mathematica, Matlab, Aspen, OpenFoam, Scienomics MAPS, LAMMPS, Enhanced Monte Carlo, MPI, Open-MP, MS-Windows (all), Linux, Unix, workstations, administration and maintenance of clusters