Computational Engineering Commons^™

Simulation Of Stress, Deformation, And Vibration In Unlubricated Ball Bearings At Varying Rotational Speeds, Billy Dwiki, Moh. Hartono

Journal of Mechanical Engineering Science and Technology (JMEST)

Bearings are critical components in rotating machinery, and their performance is highly influenced by operational factors such as rotational speed, load, and lubrication. This study aims to analyze the deformation, stress, and dynamic behavior of SAE 52100 bearings under dry operating conditions at various rotational speeds, as well as to propose mitigation strategies for high-speed industrial applications. A finite element simulation was conducted using ANSYS R19.2 to evaluate the total deformation, equivalent elastic strain, Von Mises stress, and vibrational characteristics of a 6204-type SAE 52100 bearing. The simulations were performed across a speed range of 600 to 2000 RPM under …

Signal Modeling Of High Purity Germanium Detectors, Brooke Parker Thibodeau

Honors Scholar Theses

Pulse shape analysis can be used to analyze radiation incident on a semiconductor diode detector. Finite element analysis (FEA) can be used to simulate high purity germanium detectors with user-specified geometry, impurity concentration, and bias voltage. Subsequent streamline calculation can be used to conduct pulse shape analysis for single and multiple site gamma-ray interactions within the detector volume. Cross sections of the detector can be visualized by contour plots of the electric field, drift velocity magnitude, and collection time, as well as t30 and t90 rise-time values.

Method Of Embedded Imperfections For The Direct Simulation Of Deformation Instabilities In Film-Substrate Structures, Siavash Nikravesh Kazeroni

Mechanical Engineering ETDs

In this dissertation, a novel finite-element methodology called “embedded imperfections” is proposed and employed for computationally simulating various types of deformation instabilities observed in film-substrate structures subjected to mechanical loading. The approach involves the incorporation of elements having distinctive material properties within the film-substrate interface. One can interpret this practice as a deliberate distribution of material defects within the numerical model. It has been shown that embedded imperfections not only can trigger the onset of instability, but also can lead to “direct” simulation of deformation instability problems in that primary and subsequent instability modes can all be captured in a …

Perturbed Stress Field Of The Human Lens Capsule After Cataract Surgery, Kurt Ameku, Caleb Berggren, Ryan M. Pedrigi

UCARE: Research Products

Current modeling of the human lens capsule has been focused on the mechanism of accommodation and its decline with age, but few studies have modeled the effects of cataract surgery and quantified the altered mechanical environment introduced by the procedure. The goal of this study is to develop the first fully 3-D finite element model of the post-surgical human lens capsule with an implanted device in order to characterize lens capsule mechanics after cataract surgery. The model demonstrates a highly perturbed stress field compared to the native state, which we hypothesize is the primary driving force behind the long-term errant …

Development Of A Statistical Shape-Function Model Of The Implanted Knee For Real-Time Prediction Of Joint Mechanics, Kalin Gibbons

Boise State University Theses and Dissertations

Outcomes of total knee arthroplasty (TKA) are dependent on surgical technique, patient variability, and implant design. Non-optimal design or alignment choices may result in undesirable contact mechanics and joint kinematics, including poor joint alignment, instability, and reduced range of motion. Implant design and surgical alignment are modifiable factors with potential to improve patient outcomes, and there is a need for robust implant designs that can accommodate patient variability. Our objective was to develop a statistical shape-function model (SFM) of a posterior stabilized implant knee to instantaneously predict output mechanics in an efficient manner. Finite element methods were combined with Latin …

Elastic Linear Analysis Of Connecting Rods For Single Cylinder Four Stroke Petrol Engines Using Finite Element Method, Didin Zakariya Lubis, Andoko Andoko

Journal of Mechanical Engineering Science and Technology (JMEST)

A connecting rod is one of the most critical parts in engine assembly which transfers energy from the piston to the crankshaft. The connecting rod mainly undergoes tensile and compressive loading under engine cyclic process. The forces acting on the connecting rod are forces due to maximum combustion pressure and forces due to the inertia of the connecting rod. This research aimed to analyze the design of the connecting rod of single-cylinder four-stroke engines. This study used CAD software for modeling and structural design. Stresses generated across all the locations of the connecting rod were evaluated using FEA Software. Elastic …

Analytical And Numerical Modeling Of Cavity Expansion In Anisotropic Poroelastoplastic Soil, Kai Liu

LSU Doctoral Dissertations

Cavity expansion/contraction problems have attracted intensive attentions over the past several decades due to its versatile applications, such as the interpretation of pressuremeter/piezocone penetration testing results and the modelling of pile installation/tunnel excavation in civil engineering, and the prediction of critical mud pressure required to maintain the wellbore stability in petroleum engineering. Despite the fact that various types of constitutive models have been covered in the literature on this subject, the soils and/or rocks were usually treated as isotropic geomaterials.

In recognition of the above fact, this research makes a substantial extension of the fundamental cavity expansion theory by considering …