Passion for mathematics and research

2009 SMAI-GAMNI best Ph.D thesis in France and 2009 ECCOMAS Outstanding doctoral thesis award in Europe

Dr. Elie Hachem completed his PhD at CEMEF, Center for material forming, MINES ParisTech, Sophia-Antipolis in 2009. His dissertation work was performed on applied mathematics and computational mechanics, advised by Prof. Thierry Coupez and Dr. Elisabeth Massoni.

Elie Hachem, Doctor of MINES ParisTech since Sept. 4th 2009

Using advanced numerical methods to conjugate heat transfer, turbulence modelling, radiative heat transfer and incompressible flows, Dr. Hachem showed in his thesis that the simulation of complex 3D industrial furnaces was possible.
Seven industrial partners were involved in this project. Their aim: “A better understanding of the thermal history of the load and the temperature distribution in their furnaces”.
This point is critical for the final microstructure and the mechanical properties of the treated workpieces and can directly determine their final quality in terms of hardness, toughness and resistance.

A mathematical accurate analyze is difficult because of the complex three-dimensional structure of the furnace, considering also the joined aspects such as the thermal coupling of fluids and solids, turbulent convection, thermal radiation, location of the heated objects, the burners, and the given geometry.

“How can we answer this industrial demand, particularly when such processes should have lower energy consumption and pollutant emissions?”


That was a great challenge and Elie was highly motivated. His main objective for three years was to make possible understand and better model the heat treatment process.

First, the resolution must take into account what is happening at the same time in the furnace chamber and within the workpieces. In addition, the numerical resolution must consider any specified furnace geometry, thermal schedule, parts loading design, initial operation conditions, or performance requirements.

Therefore, Dr. Hachem together with his advisors led a huge theoretical and computational campaign in different domains of computational mechanics and applied mathematics. This step was essential in order to obtain the correlated models and methods for predicting the furnace behaviour and heat transfer processes of the workpieces.

Finally, a novel multidomain approach to treat the solid and fluid interaction was developed.


Various stabilized finite element methods to solve the heat transfer and turbulent fluid flows were implemented. The combinations of these techniques into one global direct resolution made this work as an outstanding doctoral thesis.

3D direct simulation of heating process inside an industrial furnace
using two burners: temperature and streamlines evolution

It has been awarded twice by:
- SMAI-GAMNI in France as the best PhD thesis in industrial and applied mathematics,
- ECCOMAS, the best two-PhD thesis in computational mechanics in all Europe.

 Working three years in an advanced laboratory on a challenging project definitely opens the mind!
Elie found his “scientific family” at CEMEF where he is currently an assistant reseacher. ‘It is a very good environment for innovative research. Interaction between researchers, students and industrial partners is important; it gives the appropriate basis of a good scientific work.
His field of research is still the ‘fluid-structure interaction’ initiated with his thesis project. His aim is double: developing his own research activity related to applied mathematics as well as increasing the interactions with other CEMEF research teams, providing them with new numerical solutions. ‘It is so rewarding to realize all can still be done’.

Air cooling of two heated solid objects in a 2D environment

Academic background in Lebanon & a one way ticket to France and Research


Elie obtained an undergraduate degree in Pure Mathematics from the Faculty of Sciences, Lebanese University, then pursued with a first M.S. in Applied Mathematics entitled: “Computer Sciences & Finance”. After a 1-year job at the R&D of a well respected bank, his passion for the research in applied mathematics drove him again to obtain another research master entitled “Numerical Analysis and Partial Differential Equations” from the Faculty of Sciences of Saint-Joseph, University in Lebanon.
There, one of his professors from Paris 6 University and Ecole Polytechnique chose him to do an internship at the Centre of Applied Mathematics at Ecole Polytechnique. It gave him the opportunity to affirm his strong desire of pursuing a PhD thesis in the field of applied mathematics.
CEMEF, Centre for material forming, one of MINES ParisTech labs located at Sophia Antipolis, corresponds exactly to Elie’s intentions and expectations for an advanced joint industry-research PhD program.

Heating of a solid object placed next to the burner: Temperature evolution in the furnace and inside the solid


If you want to know more about Elie Hachem activities, consult his professional webpage: