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Mechanical and Aerospace Engineering Dissertations - Archive

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Articles 61 - 90 of 266

Full-Text Articles in Mechanical Engineering

Set-Theoretic Frameworks For Online Optimization, Estimation, And Control, Dignata Bhattacharjee Aug 2021

Set-Theoretic Frameworks For Online Optimization, Estimation, And Control, Dignata Bhattacharjee

Mechanical and Aerospace Engineering Dissertations - Archive

This research is primarily focused on developing online frameworks, which are suited to real-time implementation, for performance optimization, estimation, and control of dynamical systems using set-theoretic concepts and/or having set-theoretic interpretations. First, two perturbation-based extremum seeking control schemes, based on the classical setup and equipped with novel adaptation laws for the perturbation signal amplitudes, are proposed for general single input single output nonlinear systems. The proposed schemes are able to extremize steady-state system output in a practical asymptotic sense, i.e., the system is driven to an arbitrarily small set centered at the true steady-state optimal operating point. The next development …


Uncertainty Propagation, Control, And Estimation Of Stochastic Dynamic Systems Using Generalized Polynomial Chaos Expansion, Rajnish Bhusal Aug 2021

Uncertainty Propagation, Control, And Estimation Of Stochastic Dynamic Systems Using Generalized Polynomial Chaos Expansion, Rajnish Bhusal

Mechanical and Aerospace Engineering Dissertations - Archive

In recent years, uncertainty propagation has emerged as an important research area in the field of dynamical systems. The growing interest in this area arises out of the need to develop computationally efficient approaches to predict the evolution of a system subject to uncertainties. To this end, this dissertation is focused on developing computational frameworks for uncertainty propagation, control, and state estimation of stochastic dynamical systems using the generalized polynomial chaos (gPC) expansion technique. In the first part of this dissertation, the construction of gPC expansion is presented in general. The novelty of this dissertation lies in developing a mixed …


Computational Investigation Of Energy Dissipation Through Progressive Failure In Tailored Composite Structures Via Explicit Finite Element Analysis, Anirudh Srinivas Aug 2021

Computational Investigation Of Energy Dissipation Through Progressive Failure In Tailored Composite Structures Via Explicit Finite Element Analysis, Anirudh Srinivas

Mechanical and Aerospace Engineering Dissertations - Archive

In this study, energy dissipation in structures implementing a previously developed, analytically modeled, and experimentally validated composite tailoring concept is investigated using an explicit finite element approach. The tailored composite structures consist in a series connection of parallel alternate load paths of tailored length and thickness. The advantage of the tailored structure when compared to an untailored conventional structure is that when subjected to a tensile load, the response of the tailored composite structure is characterized by progressive failure of the load paths resulting in increased energy dissipation. The tailored composite structure is modeled for IM7-8552 composite material using a …


Laminar Swept And Cross Shockwave/Boundary-Layer Interactions, Jiss Jacob Sebastian Aug 2021

Laminar Swept And Cross Shockwave/Boundary-Layer Interactions, Jiss Jacob Sebastian

Mechanical and Aerospace Engineering Dissertations - Archive

Shockwave/boundary-layer interactions are considered one of the most complex problems in high-speed gas dynamics, and numerous studies have been carried out for more than eighty years to understand the fundamental physics. A numerical study was performed using fin-plate configurations to study the three-dimensional swept and cross shockwave/ laminar boundary-layer interactions. All the interactions studied were strong enough for the boundary layer to separate. In the first part, swept shock interactions between a laminar boundary layer and the shockwave induced by a sharp fin mounted perpendicularly on a flat plate were studied. Different flow conditions were investigated at freestream Mach numbers …


Design, Operation And Maintenance Of Direct And Indirect Evaporative Cooling Systems In Data Center Thermal Management, Ashwin Siddarth Aug 2021

Design, Operation And Maintenance Of Direct And Indirect Evaporative Cooling Systems In Data Center Thermal Management, Ashwin Siddarth

Mechanical and Aerospace Engineering Dissertations - Archive

Evaporative cooling is an alternative data center cooling solution that presents significant energy cost savings in acquisition and operation when compared to conventional air conditioning and mechanical refrigeration systems. This research focuses on developing a deeper understanding in implementing, operating and maintaining evaporative cooling systems integrated with air-side economization to realize the energy savings potential in data center cooling. The goal of the research is to develop a comprehensive guide to assess and contrast different approaches of evaporative cooling being used in data center cooling and provide guidance in improving water and energy efficiency. An air handling unit (AHU) serves …


Characterization And Enhancement Of Mechanical Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Rhugdhrivya Rane Aug 2021

Characterization And Enhancement Of Mechanical Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Rhugdhrivya Rane

Mechanical and Aerospace Engineering Dissertations - Archive

Fused filament fabrication is one of the most common and widely used additive manufacturing techniques. Owing to its ease of use, availability and cheap feedstock it provides a significant advantage over other AM techniques. But these advantages are overshadowed by the fact that FFF parts show high anisotropy and reduced mechanical properties as compared to conventional manufacturing techniques. Literature review of previous research works show multiple approaches to enhance the mechanical properties of FFF parts but each of these techniques have limitations to either the geometries that can be printed or involve complex expensive setups. In one such technique a …


Shape Modeling, Attitude Estimation, And Classification Of Artificial Resident Space Objects (Rso) Using Photometric Light Curves, Katiyayni Balachandran Aug 2021

Shape Modeling, Attitude Estimation, And Classification Of Artificial Resident Space Objects (Rso) Using Photometric Light Curves, Katiyayni Balachandran

Mechanical and Aerospace Engineering Dissertations - Archive

Light curve inversion (LCI) has proven valuable in using photometric measurements to optimize various physical parameters of a resident space object (RSO) such as rotational period about its own spin axis, pole orientation and others. Other characteristics such as shape and size are dependent on the surface brightness. To accurately determine size, shape, spin rate, or attitude information of an unresolved resident space object, photometry is required to capture the relatively rapid changes in brightness that these objects can exhibit. LCI has been developed significantly for asteroids, although not fool-proof for artificial RSOs. Satellites and space debris, unlike asteroids, are …


Theoretical And Experimental Analysis And Optimization Of Thermal Conduction In Electrochemical And Latent Heat Energy Storage Systems, Amirhossein Mostafavi Aug 2021

Theoretical And Experimental Analysis And Optimization Of Thermal Conduction In Electrochemical And Latent Heat Energy Storage Systems, Amirhossein Mostafavi

Mechanical and Aerospace Engineering Dissertations - Archive

Phase change materials (PCMs) are used commonly for energy storage purposes. Thermal energy can be stored in a PCM with a variety of configurations such as PCM slabs, cartesian and cylindrical finned systems. Heat transfer in PCM storage systems can be from a heat transfer fluid (HTF) or a heat source at constant temperature to adjacent PCM. The rate of heat transfer is limited by thermal properties. Fin insertion can improve the heat transfer inside the PCM. Chapters 2 and 3 derive and solve the governing energy equations to determine the transient temperature distribution in the PCM due to the …


Real-Time Material State Assessment Of Composites Using Artificial Intelligence And Its Challenges, Muthu Ram Prabhu Elenchezhian May 2021

Real-Time Material State Assessment Of Composites Using Artificial Intelligence And Its Challenges, Muthu Ram Prabhu Elenchezhian

Mechanical and Aerospace Engineering Dissertations - Archive

Over several decades of careful experimental investigation and exhaustive development of discrete damage analysis methods including integrated computational mechanics methods, our community knows a great deal about how discrete defects such as matrix cracks and defect growth (e.g. delamination) can be predicted in structural composites. For many practical situations controlled by laminated multiaxial composite structures, the loss of performance and “sudden death” end of life is controlled by defect coupling which becomes a precursor to fracture plane development. These interaction sequences are highly dependent on local details of manufacture, design configurations, and loading for a given application material and influenced …


Cooling Efficiency Improvement Of A Data Center Using Optimized Cabinet Design And Hybrid Cooling With High Inlet Conditions Of Single-Phase Coolant And Air, Uschas Chowdhury May 2021

Cooling Efficiency Improvement Of A Data Center Using Optimized Cabinet Design And Hybrid Cooling With High Inlet Conditions Of Single-Phase Coolant And Air, Uschas Chowdhury

Mechanical and Aerospace Engineering Dissertations - Archive

The objective of this study is to improve and optimize the cooling efficiency of liquid and air cooling from server to room level while applying best practices in the industry. The effect of increased air and coolant temperature has been explored through a literature survey and studies are conducted from device level to room level for air and liquid cooling. Three major aspects are considered. A closed-form air cooling solution is proposed for high-powered racks in a modular data center equipped with in-row coolers. Direct-to-chip liquid cooling technology is extensively studied at the server level for raised air and coolant …


Impact Of Material Models On Immersion Cooled Electronics Packages And Reliability Assessment For Chip-Package Interaction, Tushar Jashvantbhai Chauhan May 2021

Impact Of Material Models On Immersion Cooled Electronics Packages And Reliability Assessment For Chip-Package Interaction, Tushar Jashvantbhai Chauhan

Mechanical and Aerospace Engineering Dissertations - Archive

The immersion cooling for IT equipment has been around for decades. From thermal energy management perspective, immersion cooling is better than traditional cooling technology. However, there is need for more work in open literature when it comes to impact of immersion cooling on the reliability of IT equipment to make it commercially implemented. Detailed study of material compatibility of the various electronics packaging materials for immersion cooling is essential to understand their failure modes and reliability. The stiffness and thermal expansion are critical material properties for electronics mechanical design. This part of the study mainly focuses on two things. The …


Nanoscale Mechanics Of Disordered Biomolecules In Brain, Md Ishak Khan Dec 2020

Nanoscale Mechanics Of Disordered Biomolecules In Brain, Md Ishak Khan

Mechanical and Aerospace Engineering Dissertations - Archive

The long-term objective of this dissertation is to link blast-induced traumatic brain injury (TBI) with multiscale, multiphysics damage evolution in the brain using experimentally verifiable computations and simulations. The short-term goal is to conduct modeling and simulation to correlate dynamic mechanical loading to damage in sub-axonal components. It is known that the interior of the brain at the macroscale (10^-1 m) is composed of two distinct components, the grey matter, and the white matter. Within the cortex, the grey matter primarily takes the form of cortical columns (mesoscale: 10^-3 m), which are six layered structures, each composed of 8-10 thousand …


Analytical And Experimental Studies On Mixing In Supersonic Flows, Vijay Gopal Dec 2020

Analytical And Experimental Studies On Mixing In Supersonic Flows, Vijay Gopal

Mechanical and Aerospace Engineering Dissertations - Archive

Mixing enhancement in supersonic flow is an important domain of research for enabling the realization of efficient and scalable high speed air-breathing engines (scramjet). Introducing streamwise vorticies in supersonic flow and tailoring their interactions for mixing enhancement is the primary motivation for the present research study. Leveraging the research performed in the group at the Aerodynamics Research Center (ARC), systematic experimental studies on mixing enhancement is carried out in supersonic flows by tailoring the selected modes of streamwise vortex interactions with the aid of in-house developed reduced order method VorTX. This method utilizes the lifting line-vortex theory in supersonic flow …


Automating Aerospace Synthesis Code Generation A Tool For Generic Vehicle Design And Technology Forecasting, Thomas Peter Mccall Dec 2020

Automating Aerospace Synthesis Code Generation A Tool For Generic Vehicle Design And Technology Forecasting, Thomas Peter Mccall

Mechanical and Aerospace Engineering Dissertations - Archive

The principal development and deliverable of this research is a generic synthesis assembling decision support environment for early conceptual design that automates the assembly of synthesis architectures for enhanced product exploration and technology forecasting. The objective of this research is to develop a baseline environment to assess complex vehicle automated synthesis architecture synthetization procedures for adaptation into a greater cognitive system. This tool has been developed as a precursory and developmental task in an initiative towards an artificial intelligence design and research assistant peer. The artificial intelligence peer is a perceived course for future design system evolution in the continued …


Theoretical Modeling Of Heat And Mass Transfer Processes In Phase Change And Electrochemical Energy Storage Systems, Mohammad Parhizi Aug 2020

Theoretical Modeling Of Heat And Mass Transfer Processes In Phase Change And Electrochemical Energy Storage Systems, Mohammad Parhizi

Mechanical and Aerospace Engineering Dissertations - Archive

Theoretical understanding of heat and mass transfer processes in energy storage and conversion devices is of much interest for a wide variety of engineering applications. Two commonly used mechanisms for energy storage are electrochemical energy storage, such as in Li-ion cells, and phase change based energy storage, such as in phase change materials (PCM). Previous studies show that heat and mass transfer in both PCMs and Li-ion cells are critical processes affecting the performance and safety of these systems. This dissertation investigates several theoretical aspects of heat and mass transfer in these energy storage systems, with the goal of improving …


Finite Element Based Methodology To Predict Fatigue Compression Failure In Composite Based On Fiber Kinking Damage Model, Md Saddam Hossain Aug 2020

Finite Element Based Methodology To Predict Fatigue Compression Failure In Composite Based On Fiber Kinking Damage Model, Md Saddam Hossain

Mechanical and Aerospace Engineering Dissertations - Archive

Advanced polymer matrix composites are widely used in designing high-performance and lightweight spacecraft, rotorcraft, and automotive structures, due to its superior performance such as specific stiffness, specific strength, and toughness, which are appealing in reducing the weight of these structures. One critical factor that limits the efficient design of structures composed of fiber-reinforced composites (FRP) is the vulnerability of the material under compression loading since compressive strength of FRP material is typically a lot less compared to the tensile strength. Moreover, composite structure may undergo compression loading either by accidentally or by deliberately, large margins of safety are usually imposed …


A Scaling Investigation Of Feasibility And Hover Endurance For Electric Quasi Quadrotor Configurations, Budhyant Venepalli Aug 2020

A Scaling Investigation Of Feasibility And Hover Endurance For Electric Quasi Quadrotor Configurations, Budhyant Venepalli

Mechanical and Aerospace Engineering Dissertations - Archive

Motivated by recent developments in distributed propulsion electric vehicles, an effort is made in the present study to numerically investigate the upper bound of hover endurance achievable by electric quasi-quadrotors at various mass scales in the range of 0.1 kg to 10000 kg total vehicle mass. A feasible rotor propulsion pod design space is determined considering physics-based conceptual design constraints defined by blade tip Mach number and Reynolds number to ensure effective and energy-efficient generation of lift. A conceptual level scaling optimization for two-bladed rotor quasi-quadrotors was carried out at constant blade tip speed. A momentum theory model, a blade …


A Molecular Scale Study Of Cavitation Growth And Shock Response In Soft Materials, Khandakar Mahmud Aug 2020

A Molecular Scale Study Of Cavitation Growth And Shock Response In Soft Materials, Khandakar Mahmud

Mechanical and Aerospace Engineering Dissertations - Archive

Cavitation is a mechanism through which small vapor-filled cavities are formed in a liquid medium due to rapid changes of pressure. In liquid, the cavitation bubble is created when surrounding pressure drops below the saturation vapor pressure. Here, cavitation formation due to shock wave is considered. The molecular level heterogeneous and homogenous cavitation mechanisms and bubble growth kinetics in soft gelatin hydrogel and water has been studied. Gelatin, which is derived from collagen, is frequently used as a brain simulant material. As such, the morphology of gelatin is very different from water. In the heterogeneous cavitation study, using molecular dynamics …


Experimental And Numerical Study Of Open Bath Immersion Cooling Of Microprocessors., Amirreza Niazmand Aug 2020

Experimental And Numerical Study Of Open Bath Immersion Cooling Of Microprocessors., Amirreza Niazmand

Mechanical and Aerospace Engineering Dissertations - Archive

The increase on demand of communication and networking has resulted to increase for more powerful servers and bigger data centers. With increase the power of electronics, thermal management and cooling of the equipment become a gigantic challenge due to lower surface, they have higher power density and traditional methods of cooling become ineffective. Generally, air cooling method is the first option for cooling of the electronics due to cheaper price. To increase the efficiency and capacity of cooling liquid immersion cooling is used due to higher thermal properties like heat capacity and thermal conductivity compare to air. Two methods of …


Hypoid Gear Noise And Vibration Control In Automotive Rear Axle Systems, Chia-Ching Lin Aug 2020

Hypoid Gear Noise And Vibration Control In Automotive Rear Axle Systems, Chia-Ching Lin

Mechanical and Aerospace Engineering Dissertations - Archive

Gear whine is a key issue for the vehicle powertrain system, and the design of a quiet, reliable driveline system is highly desirable for the automotive industry. From past studies, the main source of excitation for gear vibration and noise is the transmission error (TE), which generates the dynamic mesh force between the gear teeth. Then the vibration transmits through the flexible axle components and radiates off from the surface of the axle housing structure. The dynamic responses of the hypoid geared rotor system in the rear axle have a significant effect on the performance of noise, vibration, and harshness …


A Multiscale Study Of Cavitation Mechanism And Damage In Soft Materials, Fuad Hasan Aug 2020

A Multiscale Study Of Cavitation Mechanism And Damage In Soft Materials, Fuad Hasan

Mechanical and Aerospace Engineering Dissertations - Archive

Cavitation is defined as the formation and growth of the gaseous bubble in bulk liquid due to the tensile pressure followed by the violent collapse. The collapse of the bubble is particularly significant due to its potential to cause damage to relatively stronger materials by either creating pressure waves (symmetric collapse) or liquid jet (asymmetric collapse). The study of cavitation in soft materials (e.g., tissue, brain, gelatin gel, etc.) has, therefore, gained a fair share of attention in the scientific communities. Recent studies have indicated that cavitation could be one of the leading causes of the mild Traumatic Brain Injury …


Molecular Level Mechanical Properties Of Ultra High Temperature Ceramics And Their Nanocomposites, Md Riaz Kayser Aug 2020

Molecular Level Mechanical Properties Of Ultra High Temperature Ceramics And Their Nanocomposites, Md Riaz Kayser

Mechanical and Aerospace Engineering Dissertations - Archive

Ultra High-Temperature Ceramics (UHTC) have been of great interest in the spacecraft, aerospace, and aeronautic industry due to their high melting point and their potential application as a protective material for the stagnation areas of leading edges. In this work, the effect of nanoparticle reinforcement for achieving tailored mechanical properties of UHTC’s has been studied. Two different material systems have been considered, namely the ZrB2-based and the HfO2-based nanocomposites. In the first study, the grain boundary driven mechanical behavior of polycrystalline ZrB2 and ZrC-ZrB2 nanocomposites using large-scale molecular dynamics simulations have been performed. The atomistic models of polycrystalline ZrB2 and …


Reliability Enhancement Of Heterogeneous 3d Integrated Circuit And Characterization Of Thermal Interface Material, A S M Raufur Chowdhury Aug 2020

Reliability Enhancement Of Heterogeneous 3d Integrated Circuit And Characterization Of Thermal Interface Material, A S M Raufur Chowdhury

Mechanical and Aerospace Engineering Dissertations - Archive

Electronic products require high functional integration in small footprints with lower cost. At the same time, it is required to maintain effective communication between the IC’s and the electronic systems. Various challenges are arising due to these factors such as signal processing time, heat dissipation, structural integrity, chip package interaction which need to be dealt effectively during electronic packaging. 3D stacking of the processors and the components accomplishes these goals and in high computing application it reduces the delay. Through-silicon via (TSV) is the heart of 3D integration, and the stacking of chips is emerging now as a powerful tool …


Attraction, Transport And Release Of Water Fleas’ Ephippia For Migration, Xiang Wang Aug 2020

Attraction, Transport And Release Of Water Fleas’ Ephippia For Migration, Xiang Wang

Mechanical and Aerospace Engineering Dissertations - Archive

Planktonic crustaceans of the genus Daphnia live in aquatic environments. Although they are lack of walking and flying capabilities, they have developed adaptations that facilitate the dispersal of their dormant forms, ephippia to cross terrestrial barriers and reach neighborhood waterbodies. It increases the survival rate of their species. A possible way for this spread to occur is the transport of their ephippia through waterfowls’ legs. Yet, little is known about the key role of the legs in the dispersal and the main mechanisms. The ephippia first get attached to the waterfowls’ legs. The waterfowls may then carry these ephippia to …


Investigation Of The Impact Of Material Models On Reliability Assessment Of Electronic Packages, Abel Misrak Aug 2020

Investigation Of The Impact Of Material Models On Reliability Assessment Of Electronic Packages, Abel Misrak

Mechanical and Aerospace Engineering Dissertations - Archive

Drop testing, thermal cycling, power cycling, etc. are some of the tests used to assess the reliability of new electronic products. However, performing experimental study of every new design is costly and time consuming. Computational tools are often employed to perform the required reliability analysis in a shorter time period and save valuable resources. Extensive set of material characterization work needs to be done before an accurate material model can be developed and used in computational analysis. Structural components such as printed circuit boards (PCBs) are critical in the thermomechanical reliability assessment of electronic packages. The bulk material properties of …


Heat Transfer Measurements And Enhancement For Materials And Processes In Polymer Extrusion Based Additive Manufacturing, Hardikkumar Mangaldas Prajapati May 2020

Heat Transfer Measurements And Enhancement For Materials And Processes In Polymer Extrusion Based Additive Manufacturing, Hardikkumar Mangaldas Prajapati

Mechanical and Aerospace Engineering Dissertations - Archive

Additive manufacturing (AM) is a burgeoning method for manufacturing over the subtractive manufacturing methodologies. Among the various method of polymer additive manufacturing the fused deposition modeling (FDM) also known as 3D printing is the most popular technique. In this technique, a rastering extruder dispenses a thermoplastic material on to a bed at a temperature greater than its glass transition temperature to build the part. Due to the additive nature of the process, AM introduces several challenges related to functional properties such as strength, thermal conductivity, etc of the eventual part. Measurement of thermal conductivity of additively manufactured polymer samples in …


Reinitiation Mode Study Of Highly Irregular Detonation, Nandakumar Vijayakumar May 2020

Reinitiation Mode Study Of Highly Irregular Detonation, Nandakumar Vijayakumar

Mechanical and Aerospace Engineering Dissertations - Archive

The propagation of detonation waves is governed by their stability characteristics. Interest in highly unstable detonation grew when early experiments revealed limits of operation to be directly proportional to the stability of detonation. This research focuses on reinitiation pathways of highly irregular self-sustaining detonation. This is an important aspect of stability which is not yet fully understood, while many possible mechanisms have been proposed in the literature. First, a one-dimensional instability model simulation was performed using a global one-step chemistry mechanism to understand the different unstable modes by increasing the activation energy of a mixture of hydrogen and oxygen. The …


Measurement And Optimization Of Thermal Transport Phenomena For Weld Strength Improvement In Polymer Extrusion Based Additive Manufacturing, Darshan Babu Ravoori May 2020

Measurement And Optimization Of Thermal Transport Phenomena For Weld Strength Improvement In Polymer Extrusion Based Additive Manufacturing, Darshan Babu Ravoori

Mechanical and Aerospace Engineering Dissertations - Archive

Additive manufacturing (AM) processes involve layer-by-layer addition of material to fabricate a 3-dimensional part. AM offers significant design and manufacturing flexibility compared to traditional manufacturing approaches. The major challenge in polymer-based additive manufacturing (AM) is that printed parts often have poor thermal/structural properties. These properties depend on weld strength of filaments and which intern depends on the degree of healing/neck growth between deposited polymers. The major contribution of this dissertation is understanding the importance of heat transfer during the printing process on the polymer neck growth and presented with techniques to improve the thermal and structural strength of finished part. …


Design And Optimization Of Thermal Management Approaches In Data Center Applications, Rajesh Kasukurthy May 2020

Design And Optimization Of Thermal Management Approaches In Data Center Applications, Rajesh Kasukurthy

Mechanical and Aerospace Engineering Dissertations - Archive

In the present day to day life, Internet of Things (IOT) is everything, i.e., Internet and telecommunication is needed for almost every task of our life, which require data centers. These data centers provide various facilities such as, data processing, storage, transmission, maintenance, operations etc., To perform these tasks, a huge amount of power is consumed, which in turn generates large amount of heat. As these data centers are to be made operational throughout the year, cooling of data centers is of utmost importance. The continued increase in heat flux at the chip level due to new and robust technology …


Design Optimization Of An Elastically Supported Multi-Beam Rotordynamic System To Minimize Flexural Response With Considerations For Robustness, Bret R. Hauser May 2020

Design Optimization Of An Elastically Supported Multi-Beam Rotordynamic System To Minimize Flexural Response With Considerations For Robustness, Bret R. Hauser

Mechanical and Aerospace Engineering Dissertations - Archive

Modern rotating machines are often required to operate with a small physical footprint and/or overall weight; necessitating that they utilize wide-ranging shaft speed to accomplish needed power levels. It is not uncommon that these designs also be required to support operation through a speed range encompassing multiple Critical Speeds while also limiting flexural vibrations to acceptable levels. Design optimization of this class of problem can be particularly difficult in that responses can be highly multi-modal and, when coupled with Finite Element (FE) solvers meet the conditions of a High Dimensional, Computationally Expensive Black Box (HEB) system. Because of this, some …