Advanced composites and AFP
Defect modeling, resin-rich regions, tow gaps, thermoplastic veils, and fiber waviness reduction in automated fiber placement laminates.
Osimulon research portfolio
Ahmad Ravangard
I study advanced composite materials, automated fiber placement, high-fidelity simulation, and AI-supported design as a Ph.D. student in Mechanical Engineering at Old Dominion University.
Research
Reducing defects in aerospace-grade composite manufacturing.
My work combines experiments, multiphysics modeling, and data-driven methods to study tow gaps, resin-rich regions, fiber waviness, cure-induced deformation, and performance limits in automated fiber placement laminates.
Research areas
Composite manufacturing, simulation, and computation.
Multiphysics simulation
Finite-element modeling, cure kinetics, progressive failure analysis, resin flow, fluid-structure interaction, and computational fluid dynamics.
Scientific computing
MATLAB, Python, R, Fortran, C++, Wolfram Mathematica, Bash, Git, Linux, and numerical methods for integral equations and flow solvers.
Projects
Selected computational and composite studies.
Composite cure modeling
Bilamina Composite cure-induced deflection modeling
- Problem
- Predict cure-induced curvature and final deflection in a composite laminate.
- Method
- Model cure cycle temperature, degree of cure, glass-transition temperature, property evolution, thickness change, and curvature.
- Tools
- MATLAB, experimental temperature profiles, analytical laminate modeling.
- Result
- Predicted deflection compared with experimental measurements.
Kinetic theory
Integral-equation solution of the linearized BGK model for Couette flow
- Problem
- Describe rarefied Couette velocity fields from the linearized BGK model.
- Method
- Nondimensionalization, pure-shear simplification, and boundary conditions.
- Result
- Analytical reduction to an integral equation for velocity behavior.
Rarefied gas dynamics
Integral-equation analysis of Kramers flow using the linearized BGK model
- Problem
- Model rarefied gas motion over a flat plate with slip-flow behavior.
- Method
- Apply BGK linearization, boundary conditions, and asymptotic analysis.
- Result
- Integral-equation description of the Kramers velocity profile.
Numerical methods
RCIP for cornered integral equations
- Problem
- Solve singular Fredholm integral equations with corner singularities.
- Method
- Product Nystrom discretization and compressed inverse recursion.
- Result
- Stable high-accuracy integral-equation solution for BGKW Kramers flow.
Flow simulation
Coupled-pressure Navier-Stokes solver with multigrid Poisson acceleration
- Problem
- Accelerate incompressible lid-driven cavity flow simulation.
- Method
- Coupled pressure-velocity algorithm with multigrid Poisson solver.
- Result
- Reduced iteration counts and maintained benchmark accuracy.
LBM-MRT-MGM
Lattice Boltzmann MRT simulation of lid-driven cavity flow
- Problem
- Improve stability and efficiency for nearly incompressible cavity flow.
- Method
- Multiple-relaxation-time LBM with multigrid pressure correction.
- Result
- Fast, precise pressure-velocity solution for the cavity benchmark.
Publications
Papers, journals, and conference work.
Mitigating Out-of-Plane Fiber Waviness in AFP Laminates with Tow-Gaps via Selective Placement of Thermoplastic Veils
A. Ravangard, K. Celebi, S. G. Kravchenko, O. G. Kravchenko. Fibers, 13(11):145.
Effects of Biomass and Iron Catalyst on Yield of Plant-Based Graphitic Nanoplatelets
D. W. Mulqueen, A. Ravangard, J. D. Bhagatji, S. Kumar, O. G. Kravchenko. Materials Chemistry and Physics, 131629.
Compaction and Mechanical Performance of AFP Composites with Fiber Tow Gaps
A. Ravangard, O. Kravchenko. 24th International Conference on Composite Materials.
Reducing Out-of-Plane Fiber Waviness in AFP Laminate with Tow Gaps
A. Ravangard, O. Kravchenko. SAMPE Conference.
Mechanics of Resin Rich Regions Formation in AFP Preform with Staggered Fiber Tow Gaps
A. Ravangard, V. C. Jamora, J. D. Bhagatji, O. Kravchenko. Sixth International Symposium on Automated Composites Manufacturing.
Origin and Significance of Non-Uniform Morphology in AFP Composites
A. R. Ravangard, V. C. Jamora, J. D. Bhagatji, O. Kravchenko. American Society for Composites 38th Annual Technical Conference.
The Influence of Heat Transfer Due to Radiation from a Combustion Chamber
B. Razmjooei, A. R. Ravangard, L. Momayez, M. Ferchichi. Journal of Thermal Analysis and Calorimetry, 147(3):1901-1917.
Effects of Geometry on Simulation of Two-Phase Flow in Microchannel with Density and Viscosity Contrast
A. R. Ravangard, L. Momayez, M. Rashidi. Journal of Thermal Analysis and Calorimetry, 139(1):427-440.
A Numerical Investigation of Kenics Static Mixer as a Heat Exchanger in Separation and Segregation Process of Supercritical Carbon Dioxide
A. R. Ravangard, R. Kamali. Conference on Recent Advances in Aerospace and Associated Sciences.
Ph.D. in Mechanical Engineering, Old Dominion University, Norfolk, VA. M.Sc. in Aerospace Engineering, University of Tehran. B.Sc. in Mechanical Engineering, Islamic Azad University of Neyriz.
Programming, simulation, experimental characterization, composite manufacturing, numerical methods, machine learning, and technical communication.
Graduate teaching and research work across Mechanical and Aerospace Engineering, Mathematics and Statistics, Engineering Management, and NSF-funded research.
Contact