Engineering Commons^™

A Comprehensive Analysis Of Balance, Symmetry, And Center Of Mass In The Gait Cycle Of Transfemoral Amputees, Kayla T. Etienne

FIU Electronic Theses and Dissertations

The purpose of this thesis is to create a framework that assists in the transfemoral prosthesis fitting process by calculating balance and symmetry to quantify patient comfort with an understanding of bipedal locomotion and human anatomy. Three different software applications were used to compare (1) the body position during gait cycle, (2) the natural and amputee anatomies, (3) the natural and prosthetic legs, and (4) the equilibrium and torque movements of the hip, knee, and ankle joints. Models were created in Maya for analysis in Solidworks and MEL code evaluation with MatLab. The MatLab code tested combinations of joint degrees …

Toward A Fast And Accurate Modeling Strategy For Thermal Management In Air-Cooled Data Centers, Long Tran Bao Phan

FIU Electronic Theses and Dissertations

Computational fluid dynamics (CFD) has become a popular tool compared to experimental measurement for thermal management in data centers. However, it is very time-consuming and resource-intensive when used to model large-scale data centers, and may not be ready for real-time thermal monitoring. In this thesis, the two main goals are first to develop rapid flow simulation to reduce the computing time while maintaining good accuracy, and second, to develop a whole building energy simulation (BES) strategy for data center modeling. To achieve this end, hybrid modeling and model training methodologies are investigated for rapid flow simulation, and a multi-zone model …

A Constructal Approach To The Design Of Inflected Airplane Wings, Shanae Powell

FIU Electronic Theses and Dissertations

Aeroelastic instabilities such as flutter can be accurately captured by state-of-the-art aeroelastic analysis methods and tools. However, these tools and methods fall short in exposing the reasons behind the occurrence of such instabilities. In this research, the constructal law is used to discover the main cause of the variation in the flutter speed and stress distribution for inflected aircraft wings when compared to its uninflected counterpart. This law considers the design as a physics phenomenon and uses an evolutionary flow principle to explain and predict the occurrence of energy flow configurations (i.e. the flow of stresses throughout the structure).

For …

Computational Fluid Dynamic Analysis Of Microbubble Drag Reduction Systems At High Reynolds Number, John D. Goolcharan

FIU Electronic Theses and Dissertations

Microbubble drag reduction (MBDR) is an effective method to improve the efficiency of fluid systems. MBDR is a field that has been extensively studied in the past, and experimental values of up to 80% to 90% drag reduction have been obtained. The effectiveness and simplicity of MBDR makes it a viable method for real world applications, particularly in naval applications where it can reduce the drag between the surface of ships and the surrounding water. A two dimensional single phase model was created in ANSYS Fluent to effectively model the behavior of bubble laden flow over a flat plate. This …

Database-Assisted Analysis And Design Of Wind Loads On Rigid Buildings, Filmon Fesehaye Habte

FIU Electronic Theses and Dissertations

The turbulent nature of the wind flow coupled with additional turbulence created by the wind-building interaction result in highly non-uniform, fluctuating wind-loading on building envelopes. This is true even for simple rectangular symmetric buildings. Building codes and standards should reflect the information on which they are based as closely as possible, and this should be achieved without making the building codes too complicated and/or bulky. However, given the complexity of wind loading on low-rise buildings, its codification can be difficult, and it often entails significant inconsistencies. This required the development of alternative design methods, such as the Database-Assisted-Design (DAD) methodology, …

Development Of A Two-Fluid Drag Law For Clustered Particles Using Direct Numerical Simulation And Validation Through Experiments, Ahmadreza Abbasi Baharanchi

FIU Electronic Theses and Dissertations

This dissertation focused on development and utilization of numerical and experimental approaches to improve the CFD modeling of fluidization flow of cohesive micron size particles. The specific objectives of this research were: (1) Developing a cluster prediction mechanism applicable to Two-Fluid Modeling (TFM) of gas-solid systems (2) Developing more accurate drag models for Two-Fluid Modeling (TFM) of gas-solid fluidization flow with the presence of cohesive interparticle forces (3) using the developed model to explore the improvement of accuracy of TFM in simulation of fluidization flow of cohesive powders (4) Understanding the causes and influential factor which led to improvements and …

A Novel Hip Implant Using 3d Woven Composite Material – Design And Analysis, Hari Kishore Adluru

FIU Electronic Theses and Dissertations

The present research focuses on analyzing the possibility of implementing three dimensional woven composite (3DWC) materials in hip implants. The integration of 3DWCs in hip implants has the possibility to both extend the life-time and improve patient outcomes; by spatially varying mechanical properties to meet both biological needs as well as required mechanical loading. In this study, the bulk material properties of 3DWCs were varied based on woven composite architecture and determined using physics based models, which reflect the realistic geometries of fibers in compaction and preform. The multi-digital chain method combined with Extended Finite Elemental Analysis (XFEA) are adopted …

Engineering Analysis In Imprecise Geometric Models, Riccardo Gasparini

FIU Electronic Theses and Dissertations

Engineering analysis in geometric models has been the main if not the only credible/reasonable tool used by engineers and scientists to resolve physical boundaries problems. New high speed computers have facilitated the accuracy and validation of the expected results. In practice, an engineering analysis is composed of two parts; the design of the model and the analysis of the geometry with the boundary conditions and constraints imposed on it.

Numerical methods are used to resolve a large number of physical boundary problems independent of the model geometry. The time expended due to the computational process are related to the imposed …

The Development Of A Hybrid Optimization Algorithm For The Evaluation And Optimization Of The Asynchronous Pulse Unit, Eric Inclan

FIU Electronic Theses and Dissertations

The effectiveness of an optimization algorithm can be reduced to its ability to navigate an objective function’s topology. Hybrid optimization algorithms combine various optimization algorithms using a single meta-heuristic so that the hybrid algorithm is more robust, computationally efficient, and/or accurate than the individual algorithms it is made of. This thesis proposes a novel meta-heuristic that uses search vectors to select the constituent algorithm that is appropriate for a given objective function. The hybrid is shown to perform competitively against several existing hybrid and non-hybrid optimization algorithms over a set of three hundred test cases. This thesis also proposes a …

Development Of A Coupling Model For Fluid-Structure Interaction Using The Mesh-Free Finite Element Method And The Lattice Boltzmann Method, Jaime Mudrich

FIU Electronic Theses and Dissertations

In the presented thesis work, the meshfree method with distance fields was coupled with the lattice Boltzmann method to obtain solutions of fluid-structure interaction problems. The thesis work involved development and implementation of numerical algorithms, data structure, and software. Numerical and computational properties of the coupling algorithm combining the meshfree method with distance fields and the lattice Boltzmann method were investigated. Convergence and accuracy of the methodology was validated by analytical solutions.

The research was focused on fluid-structure interaction solutions in complex, mesh-resistant domains as both the lattice Boltzmann method and the meshfree method with distance fields are particularly adept …

Development Of Rear-End Collision Avoidance In Automobiles, Uttamkumar Dravidam

FIU Electronic Theses and Dissertations

The goal of this work is to develop a Rear-End Collision Avoidance System for automobiles. In order to develop the Rear-end Collision Avoidance System, it is stated that the most important difference from the old practice is the fact that new design approach attempts to completely avoid collision instead of minimizing the damage by over-designing cars. Rear-end collisions are the third highest cause of multiple vehicle fatalities in the U.S. Their cause seems to be a result of poor driver awareness and communication. For example, car brake lights illuminate exactly the same whether the car is slowing, stopping or the …