Research & Industry
My research focuses on investigating the intricate dynamics of turbulent flows and the development of novel technologies in numerical and experimental Aero-/Hydro-dynamics. The field of offshore engineering has seen significant innovation in recent years due to the increasing number of operations moving further out to sea. Offshore wind turbines, wave energy converters as well as autonomous service vessels all represent possibilities for novel research and development. Detailed Aero-/Hydro-turbulent analyses are necessary to properly design, build, maintain, and optimize the performance and dynamics of these structures and platforms. My research centers on numerical Aero-/Hydro-dynamics for renewable engineering. Combining numerical simulations, experimental testing, and machine learning, I aim to deepen our understanding of turbulent flows in offshore renewable energy devices.
Research/Industry Experience
The University of Texas at Dallas,
Starting Fall 2024
Graduate Research Assistant
Advisor: Professor Kianoosh Yousefi.
Projects:
Contributions:
Developing machine and deep learning models to predict the turbulence structure above the surface waves.
Conducting high-fidelity simulations for the interaction between marine renewable energies and surface waves.
Stevens Institute of Technology,
Spring 2019 - Summer 2020
Texas A&M University,
Fall 2020 - Fall 2023
Graduate Research Assistant
Advisor: Professor Mirjam Fürth.
Projects: Hydrokinetic Flapping Foil Turbines, Point Wave Energy Converters, Oscillating Cylinder, and Planing High-Speed Crafts.
Contributions:
Developed a home-built code designed for investigating hydrokinetic energy converters.
Investigated the hydrodynamics of Leading-Edge Vortex (LEV) over a flapping foil in swing-arm mode.
Investigated the impact of varying the foil shape parameters on the Leading-Edge Vortex (LEV) and power extraction throughout the flapping cycle in swing-arm mode.
Developed a deformable Overset mesh technique in OpenFOAM for flexible flapping foils.
Implemented the PANS turbulent modeling technique in OpenFOAM.
Proposed a numerical towing tank for the planing high-speed craft using a turbulent PANS model.
Investigated the effect of buoy shape on the power-generating ability in a point wave energy converter.
Investigated the effect of changing the wave characteristics on the power-generating ability of the spheroid buoy system.
Helped in writing grant proposals.
Front Energies, LLC
Floating System Engineering,
Summer 2022
Research & Development Engineering Intern
PI: Dr. Zhirong Shen.
Projects: Floating Offshore Wind Turbines.
Contributions:
Integrated the mooring solver (MoorDyM) with OpenFOAM by building a new linking library in OpenFOAM.
Conducted validating simulations for the moored floater of a FOWT.
Research Skills & Interests
Programming & CFD Tools: Proficient in Fortran, OpenFOAM, Mathematica, C++, GitHub, Python, Bash, Linux HPCFD, SLURM, LATEX, OpenFAST, NEMOH, Matlab, R, TensorFlow, & Keras.
Commercial Software: Proficient in SolidWorks and AutoCAD and Good in Fluent ANSYS
Interests:
Ocean and Wind Renewable Energy Applications, such as Wave Energy Converters, Hydrokinetic Turbines, and Floating Offshore Wind Turbines.
Supersonic and Transonic Flow Applications, such as Morphing Bump over a Transonic Airfoil and Moving Supersonic Intakes.
High-fidelity turbulence modelings, such as PANS and LES.
Developing CFD Tools/Codes.
Fluid-Structure Interaction Simulations
Numerical and Experimental Wind and Wave Tanks.
Planning High-Speed Crafts.
Research Collaborations
Biolistic Drug-Delivery
July 2024 - Present
Focus on the flow dynamic aspects of a novel biolistic delivery method, called “MOF-Jet”, which uses a carrier gas to deliver a payload of drug loaded metal-organic frameworks, as an alternative to needle-based administration methods.
The process is modeled with a coupled Lagrangian-Eulerian framework, in which the drug particles are injected into a porous medium using a high-speed flow. This four-way coupling method models flow-particle interactions, including particle collisions.
Collaborator:
Thomas S. Howlett, Ph.D. Student at UTD, Focuses on Lab. Experiments.
Advisors:
Professor Kianoosh Yousefi, UTD.
Professor Jeremiah J. Gassensmith, UTD.
Ship Hull Optimization
May 2022 - May 2024
Developed codes to reduce the wave resistance over a KCS hull by optimizing its shape.
Advisors:
Professor Mirjam Fürth, TAMU.
Professor Antony Jameson, TAMU.
Professor Luigi Martinelli, Princeton University.
Turbulent PANS Model
January 2023 - August 2023
Implemented different turbulent PANS models in OpenFOAM and performed validation simulations.
Advisors:
Professor Mirjam Fürth, TAMU.
Professor Sharath Girimaji, TAMU.
Modified OverSet Mesh in OpenFOAM
May 2022 - March 2024
Developed a modified OverSet meshing technique to simulate deformable moving bodies, such as flexible flapping foils, see GitHub link.
Improving the coupling library between OpenFOAM and PreCICE to perform a Fluid-Solid Interaction (FSI) simulation.
Developed with Ph.D student Karim Ahmed, Universite de Poitiers.
Advisors:
Professor Mirjam Fürth, TAMU.
Professor Ludovic Chatellier, Universite de Poitiers.
Research Mentoring/Co-Advising
Vertical Axis Wind Turbine - AIAA CLUB
July 2024 - Present
Investigated the separation phenomenon over a straight blade vertical axis wind turbines through cross-flow fan integration.
Students:
Undergraduate Students in the Department of Mechanical Engineering, The University of Texas at Dallas.
Main Advisors:
Professor Kianoosh Yousefi, The University of Texas at Dallas.
Heat Transfer from a Channel
September 2021 - Present
Investigated the naturally-driven flow behavior in channels with different aspect ratios.
Students:
Master Student in Chemical Engineering Department, Alexandria University (Remotely).
Main Advisors:
Professor Mahmoud Taha Moharam, American University of the Middle East.
Machine Learning in CFD of Transonic Flow over an Airfoil
Septemeber 2022 - October 2023
Proposed an approach to estimate the aerodynamic coefficients of airfoils in the transonic regime using Artificial Neural Networks.
Students:
Senior/M.Sc. Students at Aerospace Engineering Department, Cairo University (Remotely).
Main Advisors:
Professor Mohamed Madbouli Abdelrahman, Cairo University.
Professor Mahmoud Ayyad, Stevens Institute of Technology.
Point Wave Energy Converters
January 2021 - May 2023
Investigated different shaped surface buoys, with a focus on the power-generating ability of the system, for a single point WEC at different waves.
Students:
Junior/Senior Students at TAMU.
Main Advisors:
Professor Mirjam Fürth, TAMU.
Research Topics
Figure: Unsteady compressible viscous transonic flow over an airfoil with a morphing bump.
Figure: Mesh motion results for the case of a flexible flapping wing during a flapping cycle.
Figure: Folder structure of TurbulenceModels library, showing the implementation location of different models.
Figure: Folder structure of TurbulenceModels library, showing the implementation location of different models.
Computational Fluid Dynamics
My research endeavors encompass a multifaceted approach to advancing computational fluid dynamics (CFD) techniques in a diverse array of engineering domains. Leveraging my expertise in building in-house finite element method (FEM) and finite volume method (FVM) codes in Fortran and C++, I have developed robust tools for simulating both steady and unsteady incompressible and compressible flows, spanning from basic Euler equations to more complex Navier-Stokes formulations.
Embracing the principles of Object-Oriented Programming (OOP), I have contributed to the development of shape optimization code using Fortran. In addition, I gained the skills of dealing with different types of dynamic meshes, such as morphing and overset meshes, as well as implementing fixed meshes such as Volume-of-Fluid (VOF) and Level Set Method (LSM) in both Fortran and OpenFOAM (C++) environments.
My proficiency in parallelization techniques for High-Performance Computing (HPC) environments has been instrumental in optimizing computational efficiency. Notably, my contributions include developing libraries for mooring coupling, refining overset methods to accommodate simultaneous rigid body motion and deformation, and implementing PANS in turbulent modeling.
Figure: Compressible turbulent flow over a triangle airfoil using RANS and PANS turbulent.
Turbulent Modeling & Machine Learning
Leveraging advanced turbulence modeling techniques, including Reynolds-Averaged Navier-Stokes (RANS), Partially-Averaged Navier-Stokes (PANS), and Implicit Large Eddy Simulation (ILES), I have delved into understanding the intricate interplay of turbulent structures and their impact on fluid behavior. Recognizing the limitations of traditional modeling approaches, I will embark on integrating machine learning (ML) and deep learning (DL) techniques into turbulent simulations to augment predictive accuracy and efficiency. By harnessing the power of ML algorithms, such as neural networks and deep learning models, I aim to uncover hidden patterns within turbulent flow data and develop novel methodologies for turbulence modeling and prediction. Through projects like ML-based lift coefficient prediction for transonic airfoils (Ayman et al., 2023) and participation in OpenFOAM-Machine Learning Hackathons, I have enriched my knowledge in AI technologies and their potential for revolutionizing turbulent flow simulations. Moving forward, I am committed to further exploring the synergies between turbulent simulations and machine learning, with the ultimate goal of advancing our understanding of turbulent flows and driving innovation in engineering design and optimization.
Figure: Schematics of a WEC with a cylindrical buoy (Hamada & Fürth, 2021a).
Wave Energy Converters
One way to improve the effectiveness of the Point Wave Energy Converters (PWEC), is to optimize the buoy shape, increasing its response motions and subsequently improving the power extraction efficiency. However, the literature does not provide a single universally optimized buoy shape; it changes from study to study along with the wave characteristics (Hamada & Fürth, 2021 & 2022). Recently, the scientific community has been focusing on developing a Variable Shape PWEC, which can harvest wave energy efficiently over a wide range of sea states. The first VSPWEC was proposed by Zou & AbdelKhalik (2020). This buoy can change its shape depending on the incident wave’s characteristics. With the use of active shape optimization, optimal control algorithms, and excitation wave estimation, VSPWEC can outperform Fixed Shape PWECs due to their wider optimal operation ranges and less complex PTO units (Zou et al., 2021). The existing literature on VSPWECs relies on potential solvers and low-fidelity simulations. However, these methods may not capture the full complexity of turbulent dynamics in such applications. Therefore, there is a critical gap in understanding the turbulent behavior of VSPWEC systems, particularly regarding their interaction with the mooring system, Power Take-Off system, irregular sea waves, and harsh sea conditions. Addressing this gap through detailed turbulent simulations is essential for advancing our knowledge and optimizing the design and performance of VSPWECs. Leveraging recent advancements, such as the overset method and the integration of PANS in OpenFOAM (Ahmed et al., 2024) facilitates the execution of these simulations, offering a pathway to comprehensive understanding and optimization.
Figure: Vorticity contours around a NACA 0012 flapping foil in swing-arm mode during the down-stroke phase (Hamada & Fürth, 2023).
Flapping-foil hydrokinetic turbine
The VIV phenomenon also appears over streamlined bodies, such as foils, at high angles of attack. The flapping foil generates power by performing two main motions: heave and pitch. The main indication of the power extraction capability for the flapping-foil is the strength of the Leading-Edge Vortex (LEV) (Hamada & Fürth, 2022 & 2023). Hence, the gained power starts to fade out when the stall phenomenon appears (Karbasian et al., 2016). High-lift devices will delay the stall phenomenon of the LEV over the flapping foils. However, which type of high lift device, (flap, slat, cuff, and air slots) is the best and the time of its operation during the flapping cycle is still unclear. In addition, expanding from 2D to 3D, biomimicry from the fish fin will be used to improve the performance of the flapping foil. The motion of a fish’s fin during swimming is very similar to the flapping foil motion, simplifying the fish’s fin motion to be a rigid body, Qiang Zhong et al. (2021) showed that the induced vortices, generated during the flapping motion of the fin, are highly affected by the shape of the fish’s fin. Thus, the bio-inspired shapes from near-ground swimming fishes will increase the efficiency of energy harvesting using the flapping foil operating near the ground. However, the determination of the geometric parameters of the flapping foil, such as the aspect ratio, sweep angle, taper ratio, and twist angle is still an open area of research.
Floating Offshore Wind Turbines
Figure: FOWT subjected to a focus wave.
Floating Offshore Wind Turbines (FOWTs) have attracted growing attention in recent years due to their enormous potential to harvest wind energy in deep-water offshore regions. Numerical modeling of the moored FOWT system is important to provide an accurate and reliable CFD for moored offshore systems. Enhancing my proficiency in the realm of Floating Offshore Wind Turbines (FOWTs), I have directed my focus towards conducting high-fidelity simulations of extreme waves on these offshore structures. Employing various OpenFOAM libraries, such as Iso-Advector, waves2foam, FocusedWave, Adaptive Mesh Refinement (AMR), Overset, MoorDyn, and FloatStepper, I have endeavored to capture the intricate dynamics of wave-structure interactions. Through these simulations, I aim to unravel the intricate dynamics of turbulent flows, encompassing hydrodynamic, aerodynamic, and structural phenomena within FOWTs. Specifically, the research aims to elucidate the complex interactions between these factors, with a primary focus on the wake-wind-wave interaction and its influence on the performance and integrity of floating offshore wind farms.