Nazek Khouja

Nazek Khouja
Faculty: Business Administration Position: Part TimerE-mail: NAZEK.KHOUJA@GMAIL.COM


Nazek EL KHOUJA received his Ph.D. in October 2013 from Nantes University and M.S. in Applied Mathematics in 2010 from Amiens University. She obtained his B.S. in Mathematics from Lebanese University in 2008. She is instructor in the faculty of science department of Mathematics and faculty of Business in BAU University.



Many complex materials are obtained by transformation a moist granular assembly in a homogeneous viscoplastic paste. This transformation results from a flow set of the assembly. This is particularly the case concrete mixing. Recent work on the behavior viscoplasticity but also friction. However, only the viscoplastic character seems to have been the subject of mathematical research. In the literature, the Bingham model is used to analyze the viscoplasticity. In my work of research, the frictional character is obtained introducing a dependency pressure in plasticity yield stress Bingham model, named FVL. The work then focuses on the theoretical and numerical study of VFL. For this purpose, three types of problems are analyzed: problem with variable yield stress, FVL with regularized yield stress and discreet FVL. In particular, the existence of a solution is shown, a numerical resolution algorithm based on the existence of a fixed point is designed for non-linearity yield stress and a spatial discretization by a mixed finite element method bilinearconstant in pressure-velocity and bilinear discontinuous for stress is carried out. More, its convergence and robustness are evidenced on different geometry as Couette geometry and flow around a cylinder. Finally, the feasibility of the numerical resolution algorithm is proved in the case of a planetary mixer.


 All Publications (total number)

  • N. EL KHOUJA, N. ROQUET, B. CAZACLIU,Analysis of a regularized Bingham model with pressure-dependent yield stress, of the Journal of Non-Newtonian Fluid Mechanics, 2014
  • N. EL KHOUJA, N. ROQUET, B. CAZACLIU,Numerical modeling of frictional rheology law: application to concrete mixing, MAMERN13 : 5th International Conference on Approximation Methods and Numerical Modelling in Environment and Natural resources, April 2013.
  • N. EL KHOUJA, N. ROQUET, B. CAZACLIU, Simulation numérique d'un écoulement viscoplastique frictionnel autour d'un cylindre circulaire, CFM: XXIe congrès français de mécanique, August 2013.
  • N. EL KHOUJA, N. ROQUET, B. CAZACLIU, Frictional viscoplastic law : Modeling and application, Viscoplastic Fluids : From Theory to Application, November 2013.