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Articles 811 - 840 of 3234
Full-Text Articles in Mechanical Engineering
Precise Landing Of Vtol Uavs Using A Tether, Jeremy W. Rathjen
Precise Landing Of Vtol Uavs Using A Tether, Jeremy W. Rathjen
Graduate Theses, Dissertations, and Problem Reports (ETD)
Unmanned Aerial Vehicles (UAVs), also known as drones, are often considered the solution to complex robotics problems. The significant freedom to explore an environment is a major reason why UAVs are a popular choice for automated solutions. UAVs, however, have a very limited flight time due to the low capacity and weight ratio of current batteries. One way to extend the vehicles' flight time is to use a tether to provide power from external batteries, generators on the ground, or another vehicle. Attaching a tether to a vehicle may constrain its navigation but it may also create some opportunities for …
Cfd And Heat Transfer Analysis Of Rocket Cooling Techniques On An Aerospike Nozzle, Geoffrey Sullivan
Cfd And Heat Transfer Analysis Of Rocket Cooling Techniques On An Aerospike Nozzle, Geoffrey Sullivan
College of Graduate Studies: Theses & Dissertations
In recent years the development of rocket engines has been mainly focused on improving the engine cycle and creating new fuels. Rocket nozzle design has not been changed since the late 1960s. Recent needs for reliable and reusable rockets, as well as advancements in additive manufacturing, have brought new interest into the aerospike nozzle concept. This nozzle is a type of altitude adjusting nozzle that is up to 90% more efficient than bell nozzles at low altitudes and spends up to 30% less fuel. Since the nozzle body is submerged in the hot exhaust gasses it is difficult to keep …
Plasma Spheroidization Of Gas-Atomized 304l Stainless Steel Powder For Laser Powder Bed Fusion Process, M. Hossein Sehhat, Austin T. Sutton, Chia-Hung Hung, Ben Brown, Ronald J. O'Malley, Jonghyun Park, Ming-Chuan Leu
Plasma Spheroidization Of Gas-Atomized 304l Stainless Steel Powder For Laser Powder Bed Fusion Process, M. Hossein Sehhat, Austin T. Sutton, Chia-Hung Hung, Ben Brown, Ronald J. O'Malley, Jonghyun Park, Ming-Chuan Leu
PSMRC Faculty Research
Particles of AISI 304L stainless steel powder were spheroidized by the induction plasma spheroidization process (TekSphero-15 spheroidization system) to assess the effects of the spheroidization process on powder and part properties. The morphology of both as-received and spheroidized powders was characterized by measuring particle size and shape distribution. The chemistry of powders was studied using inductively coupled plasma optical emission spectroscopy for evaluation of composing elements, and the powder’s microstructure was assessed by X-ray diffraction for phase identification and by electron backscattered diffraction patterns for crystallography characterization. The Revolution Powder Analyzer was used to quantify powder flowability. The mechanical properties …
Calorimetric Measurements Of Lunar Regolith Simulant And Water. An Experimental Study Correlating Weight Percent Water And Temperature Change Through Periods Of Phase Change., George B. Johnson
Dissertations, Master's Theses and Master's Reports
Permanently Shaded Regions (PSRs) are cold traps located around the lunar south pole that have been confirmed to contain possible interesting quantities or volatiles such as H2O, CO2, SO2, CH4, and others. [1] The identification of these volatiles on the lunar surface was a critical step in the development of NASA’s strategic goals for scientific discoveries, sustained space travel and exploration, and re-establishing a human presence on the moon. These volatiles are vital to the future of operating in and exploring space. The LCROSS impact revealed the existence of these resources in PSRs but more information is needed about the …
Numerical Investigation On The Effect Of Spectral Radiative Heat Transfer Within An Ablative Material, Raghava S. C. Davuluri, Rui Fu, Kaveh A. Tagavi, Alexandre Martin
Numerical Investigation On The Effect Of Spectral Radiative Heat Transfer Within An Ablative Material, Raghava S. C. Davuluri, Rui Fu, Kaveh A. Tagavi, Alexandre Martin
Mechanical Engineering Faculty Publications
The spectral radiative heat flux could impact the material response. In order to evaluate it, a coupling scheme between KATS - MR and P1 approximation model of radiation transfer equation (RTE) is constructed and used. A Band model is developed that divides the spectral domain into small bands of unequal widths. Two verification studies are conducted: one by comparing the simulation computed by the Band model with pure conduction results and the other by comparing with similar models of RTE. The comparative results from the verification studies indicate that the Band model is computationally efficient and can be used to …
Analysis Of Multiple Degree-Of-Freedom Oscillatory Aquatic Propulsion, Seth Alan Brooks
Analysis Of Multiple Degree-Of-Freedom Oscillatory Aquatic Propulsion, Seth Alan Brooks
Dissertations - ALL
Propulsive performance and flow field data were experimentally measured for a two degree-of-freedom fish platform. The fish platform was designed and constructed based on the yellowfin tuna (\textit{Thunnus albacares}) that is known to be both fast and efficient. This work extends the current understanding of oscillatory aquatic propulsion to a three-dimensional fish platform with full volume flow field data and propulsive performance. A parametric sweep of trailing-edge amplitude of the caudal fin ($A$), heave-to-pitch ratio ($h^*$), and phase offset between the two degrees-of-freedom ($\phi$) was used to explore a parameter space that encompasses and extends beyond the known biological domain. …
State-Of-The-Art Of Thermal Control Solutions To Establish A Modular, Multi-Orbit Capable Spacecraft Thermal Management System Design Methodology, Robert C. Consolo Jr
State-Of-The-Art Of Thermal Control Solutions To Establish A Modular, Multi-Orbit Capable Spacecraft Thermal Management System Design Methodology, Robert C. Consolo Jr
Doctoral Dissertations and Master's Theses
Today, the exploration and exploitation of space continues to become a more common occurrence. All types of spacecraft (S/C) utilize various types of thermal management solutions to mitigate the effects of thermal loading from the unforgiving vacuum of space. Without an appropriately designed thermal system, components on-board the S/C can experience failure or malfunction due to fluctuations in temperatures either beyond the designed operational parameters or unstable oscillating temperatures. The purpose of this study is to perform a comprehensive review of technologies available today that are being used for thermal management onboard S/C in addition to investigating the means to …
Numerical Simulation Of A Cryogenic Spray, Neel Kishorkumar Shah
Numerical Simulation Of A Cryogenic Spray, Neel Kishorkumar Shah
Doctoral Dissertations and Master's Theses
Cryogenic sprays have many applications in modern engineering. Cooling of electronic equipment subject to high heat flows, surgical ablation of gastrointestinal mucosae or orbital maneuvering are a few examples of their versatility. However, the atomization of a cryogenic liquid is a complex process. During such an event, aerodynamic effects associated with secondary atomization are further affected by thermodynamic flashing. A better understanding of the characteristics of cryogenic sprays is then necessary to allow for improved design and optimization in applications. The overarching objective of this study is to document such characteristics. The numerical simulation was performed over cryogenic nitrogen spray …
A Numerical Study Of Water Entry Problems Based On Overset Meshes, Yanni Chang
A Numerical Study Of Water Entry Problems Based On Overset Meshes, Yanni Chang
Mechanical and Aerospace Engineering Dissertations - Archive
A series of numerical experiments carried out on the water entry of circular cylinders are presented in this study. A cylinder was entering into the water with a prescribed inclined angle and velocity. The interface between water and air is tracked by the Piecewise Linear Interface Calculation (PLIC) schemes in conjunction with the Volume of Fluid (VOF) method. PLIC schemes have been extensively employed in the VOF method for interface capturing in numerical simulations of multiphase flows. Dynamic overset meshes, which have been widely used for problems with relative motions and complex geometric shapes, are applied to handle the moving …
Characterization And Enhancement Of Fatigue And Fracture Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Manjarik Mrinal
Characterization And Enhancement Of Fatigue And Fracture Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Manjarik Mrinal
Mechanical and Aerospace Engineering Dissertations - Archive
Fused filament fabrication (FFF) show high anisotropy and reduced mechanical properties as compared to conventional manufacturing techniques. This happens due to the poor interlaminar bonding between the layers, as a result of premature halt of bond healing process. Previous research works show multiple approaches to improve the bond quality to enhance the mechanical properties of FFF parts, however these are complex and expensive techniques. In this work a novel print head assembly is presented to offer a simple and effective solution by applying a thermal field to the part as it is being printed to preheat the previously deposited layer, …
Internal Pressure Response Of A Human Head Surrogate Model Subject To Variable Impact Loading With Finite Element Analysis, Aaron Ronald Jackson
Internal Pressure Response Of A Human Head Surrogate Model Subject To Variable Impact Loading With Finite Element Analysis, Aaron Ronald Jackson
Mechanical and Aerospace Engineering Theses - Archive
Traumatic brain injury (TBI) from blunt impacts to the head is a major cause of brain disease and dysfunction for thousands of people every year. Each year in the United States approximately 1 million TBI cases occur causing as many as 56,000 deaths and leaving nearly 90,000 individuals with long-term disabilities. Damage resulting from a TBI occurs on a multiscale level including the macroscopic, tissue, and neuron length scale. This research focuses on correlating the macroscopic blunt impact conditions to the internal pressure developed in the coup and countercoup for water and gelatin-filled head models. Two separate 3D printed models …
Synthesis And Characterization Of Graphene-Reinforced Polymer Filaments For Additive Manufacturing, Sean Menezes
Synthesis And Characterization Of Graphene-Reinforced Polymer Filaments For Additive Manufacturing, Sean Menezes
Mechanical and Aerospace Engineering Theses - Archive
Fused Deposition Modeling (FDM) is a popular 3D printing process which uses a spool of thermoplastic polymer filament that is melted by the movable extruder printer head onto the bed to generate the required shape. The most used polymer filaments in FDM are Acrylonitrile Butadiene Styrene (ABS) and Poly Lactic Acid (PLA). However, these conventional polymer filaments have lower mechanical strength and are more susceptible to cracking as the cooler parts of the printed part shrink so much that they cause cracks to develop, leading to warping. The current investigation focuses on the synthesis of graphene, synthesis of polymer filaments …
Reverse Engineering To Create High Quality Polymer Parts Using Additive Manufacturing, Gurtej Singh Tarsem Singh Channa
Reverse Engineering To Create High Quality Polymer Parts Using Additive Manufacturing, Gurtej Singh Tarsem Singh Channa
Mechanical and Aerospace Engineering Theses - Archive
Reverse engineering is a process of recreating parts for which the tools no longer exist, reducing the cost of an original part by manufacturing it in-house or redesigning and improving the original part's function. This research demonstrates two methods to reverse engineer a part using Polyworks software, having it printed using an SLS printer and checking the accuracy of the printed part to the original scan. The part is first scanned using a Faro-Arm laser scanner to obtain the point cloud data. The two methods used to recreate and extract the STEP file are: • Exporting NURBS. • Exporting Features …
Development Of The Vehicle Configuration Compendium: A Comprehensive Data-Information-Knowledge System To Aid In High-Speed Vehicle Design, Stenila Simon
Mechanical and Aerospace Engineering Theses - Archive
The conceptual design phase is the most crucial phase in hypersonic vehicle design. Choices made during this phase will have significant impact on the success of the overall project and the feasibility of the end-product. Therefore, it is of utmost importance for the design decision-maker to be adequately informed of past-to-present projects throughout the aerospace community and lessons learned from them. This avoids wasting valuable time and resources for reinventing the wheel. There currently exists no one-stop solution in the aerospace industry to address the issue of lost data, information and knowledge in the field of high-speed vehicle design. The …
Relating Linear And Rotational Accelerations With Internal Pressures Developed Inside Human Head Surrogate Models, Arthur Thomas Koster
Relating Linear And Rotational Accelerations With Internal Pressures Developed Inside Human Head Surrogate Models, Arthur Thomas Koster
Mechanical and Aerospace Engineering Theses - Archive
Traumatic Brain Injury (TBI) is a chronic disease process that is difficult to both detect and treat. TBI can result from blast, kinetic, sonic, and electromagnet energy sources. This research focuses on correlating the bulk acceleration of a human-like head model to the localized internal pressure developed in the coup and contrecoup regions due to variable impact loading. Damage resulting in a TBI occurs on a multiscale level from the macroscale down to the damage of each individual neuron. Obtaining a relationship between bulk acceleration and localized internal pressure will allow for further correlation to the damage done on these …
Investigation Of Heat Transfer Performance Of Double Pipe Counter-Flow Heat Pipe Using Three Fluids Water, Dowtherm, And Water-Based Nanofluid, Alaa Abed Harchan Al Hasseun
Investigation Of Heat Transfer Performance Of Double Pipe Counter-Flow Heat Pipe Using Three Fluids Water, Dowtherm, And Water-Based Nanofluid, Alaa Abed Harchan Al Hasseun
Mechanical and Aerospace Engineering Theses - Archive
Heat pipes are two-phase devices, capable of converting a significant amount of energy with low losses. They have been used in several applications such as systems thermal control and cooling. The purpose of the present work is to investigate the thermal performance of a double pipe counterflow against the fluid type. The pipe is divided into three zones including evaporator, adiabatic, and condenser zones. All thermal boundary conditions are defined in terms of heating or cooling temperatures in which the operating temperatures are defined between 303 K to 470 K. using Ansys Fluent, the pipe is analyzed in two-and three-dimensional …
Prediction Of Solder Joint Fatigue Life Of Photonic Package Using ?-? Materials, Ojas Tyagi
Prediction Of Solder Joint Fatigue Life Of Photonic Package Using ?-? Materials, Ojas Tyagi
Mechanical and Aerospace Engineering Theses - Archive
Fatigue life prediction has become very important factor in reliability of any electronic components to withstand extreme thermal stresses in industrial standard. Hence, photonic packages are widely used in telecommunication and computer applications. The primary focus of this study is to determine the thermal cycles to crack initiation of solder bump used in laser array waferboard for telecommunication applications. This includes GaAs Laser chip on waferboard and Si substrate with pure Indium solder balls in between. Indium has proved higher fatigue life in various experimental studies in the field of reliability and lead-free material. Therefore, a solder ball was designed …
Analysis Of Blood Pressure Waveform For Detection And Diagnosis Of Cardiovascular Anomalies, Atul Shrotriya
Analysis Of Blood Pressure Waveform For Detection And Diagnosis Of Cardiovascular Anomalies, Atul Shrotriya
Mechanical and Aerospace Engineering Theses - Archive
Cardiovascular diseases are the leading cause of mortalities worldwide as well as in the United States. Early diagnosis and prediction of these diseases is critical to mitigate the risks to the patient. A common method to assess a person’s heart health is through the use of cuff type oscillometric devices placed on the arm of the patient. As the mean pressure in the cuff is increased the blood flow in the brachial artery becomes blocked. When the cuff pressure is reduced the blood starts flowing again; during this cycle, pressure fluctuations in the cuff are measured using a pressure transducer. …
Determination Of Guidance Laws For Uav Systems In Communication Networks Using Collision Cone Theory, Utsav Mudgal
Determination Of Guidance Laws For Uav Systems In Communication Networks Using Collision Cone Theory, Utsav Mudgal
Mechanical and Aerospace Engineering Theses - Archive
Unmanned Aerial Vehicles (UAVs), also commonly known as drones, are used in various applications, including military applications such as surveillance and intelligence-gathering as well as civilian applications such as search and rescue. The use of UAVs to form communication networks is a topic of active research interest. This thesis aims to investigate the development of guidance laws for multiple UAVs to form such communication networks. Toward this end, this thesis employs tools from collision cone theory and incorporates them with parameters used to describe a communication network. Different types of networks are evaluated for use of the guidance laws. Simulation …
Guidance Laws For N-Mobile Agents To Grip A Moving Target, Pranay Gadiya
Guidance Laws For N-Mobile Agents To Grip A Moving Target, Pranay Gadiya
Mechanical and Aerospace Engineering Theses - Archive
In this thesis, we consider the problem of n mobile agents carrying a gripper, with the objective of gripping a moving circular target. The target may move with constant velocity, or even maneuver. We develop guidance laws by which the agents can first cage the target and subsequently grip it. These guidance laws are developed based on a collision cone framework, using which the mobile agents cooperatively steer their velocity vectors in an appropriate fashion to meet their objective. It is assumed that each of the mobile agents are equipped with a lidar sensor, using which they obtain the range …
Buckling Load Optimization Of Variable Stiffness Composite Plate Using Fem And Semi-Analytical Method, Jeegar Vallabhbhai Patel
Buckling Load Optimization Of Variable Stiffness Composite Plate Using Fem And Semi-Analytical Method, Jeegar Vallabhbhai Patel
Mechanical and Aerospace Engineering Theses - Archive
The advent of new composite manufacturing techniques like Automated Fiber Placement (AFP) offers greater flexibility in structural designs by allowing curvilinear fiber paths. Hence, it is now possible to change laminate stiffness locally, thereby enabling Variable Stiffness (VS) composite structures. Such structures demonstrate superior buckling performance over traditional constant stiffness structures. However, obtaining the optimum fiber paths to improve buckling performance remains an open area of research due to the complexity of determining such fiber paths. This research investigated two approaches for optimizing fiber paths; First, a Finite Element Method (FEM) approach that utilizes linear shape functions to interpolate local …
A Modular Platform For Intrusive Diagnostics And Tps Testing In The Onr-Uta Arc-Jet Facility, Blake Anthony Hamilton
A Modular Platform For Intrusive Diagnostics And Tps Testing In The Onr-Uta Arc-Jet Facility, Blake Anthony Hamilton
Mechanical and Aerospace Engineering Theses - Archive
This work presents an approach to the design, and successful experimental implementation, of a modular platform for intrusive diagnostics and TPS testing in the ONR-UTA Arc-Heated Wind Tunnel "Leste" Facility. The harsh conditions typical of arc-jet facilities (hypersonic, high-enthalpy, chemically-reacting, continuous flows) present a challenge to the design of insertion platforms. In this work a detailed analysis of the aerothermal loads is used to aid in the design process. Specific design points for this modular platform and its ancillary instrumentation have been identified. Based on this design approach, a modular platform for intrusive diagnostics and TPS testing has been developed. …
Theoretical Prediction Of Mechanical Behavior Of Regular And Chiral Honeycombs Based On Loading Of Single Cell., Sai Krishna K. Pinnamaneni
Theoretical Prediction Of Mechanical Behavior Of Regular And Chiral Honeycombs Based On Loading Of Single Cell., Sai Krishna K. Pinnamaneni
Mechanical and Aerospace Engineering Dissertations - Archive
Cellular solids are both naturally occurring and man-made materials depending on the characteristic length or Stochastic manner, these materials exhibit a low-relative density usually 30% than the constituent solid material. Low-density cellular solids have been demonstrating superior mechanical properties in various applications from marine to aerospace and lightweight sandwich structures, which has intrigued in development of novel structured materials. Cellular solids offer great design flexibility ashowows how for the targeted geometric for the application-based industry. These materials are used in sandwich structures and come in the shape of hexagonal. An additional aspect of determining the properties and behavior is by …
Multi-Parametric And Multi-Objective Optimization Of Heatsinks For Forced And Natural Convection Based Single-Phase Immersion Cooling Of Server, Tushar Rohidas Wagh
Multi-Parametric And Multi-Objective Optimization Of Heatsinks For Forced And Natural Convection Based Single-Phase Immersion Cooling Of Server, Tushar Rohidas Wagh
Mechanical and Aerospace Engineering Theses - Archive
An increase in utility of internet-based services, cloud computing and greater performance demands due to rising AI and ML applications have led to a steep growth in GPU and CPU thermal design power. Efficient thermal management of these processors has become a bottleneck in performance enhancement and corresponding power densification of these components. Furthermore, increased pressure on data center owners to reduce power demands and move towards green computing has exacerbated the data center cooling challenges. Single-phase immersion cooling allows data center owners to not only dissipate the increasing heat fluxes efficiently but can also potentially improve equipment reliability as …
Impact Of Surface And Pore Characteristics On Fatigue Life Of Laser Powder Bed Fusion Ti–6al–4v Alloy Described By Neural Network Models, Seunghyun Moon, Ruimin Ma, Ross Attardo, Charles Tomonto, Mark Nordin, Paul Wheelock, Michael Glavicic, Maxwell Layman, Richard Billo, Tengfei Luo
Impact Of Surface And Pore Characteristics On Fatigue Life Of Laser Powder Bed Fusion Ti–6al–4v Alloy Described By Neural Network Models, Seunghyun Moon, Ruimin Ma, Ross Attardo, Charles Tomonto, Mark Nordin, Paul Wheelock, Michael Glavicic, Maxwell Layman, Richard Billo, Tengfei Luo
Mechanical and Aerospace Engineering Faculty Research & Creative Works
In this study, the effects of surface roughness and pore characteristics on fatigue lives of laser powder bed fusion (LPBF) Ti–6Al–4V parts were investigated. The 197 fatigue bars were printed using the same laser power but with varied scanning speeds. These actions led to variations in the geometries of microscale pores, and such variations were characterized using micro-computed tomography. To generate differences in surface roughness in fatigue bars, half of the samples were grit-blasted and the other half were machined. Fatigue behaviors were analyzed with respect to surface roughness and statistics of the pores. For the grit-blasted samples, the contour …
Second-Order Reliability Methods: A Review And Comparative Study, Zhangli Hu, Rami Mansour, Mårten Olsson, Xiaoping Du
Second-Order Reliability Methods: A Review And Comparative Study, Zhangli Hu, Rami Mansour, Mårten Olsson, Xiaoping Du
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Second-order reliability methods are commonly used for the computation of reliability, defined as the probability of satisfying an intended function in the presence of uncertainties. These methods can achieve highly accurate reliability predictions owing to a second-order approximation of the limit-state function around the Most Probable Point of failure. Although numerous formulations have been developed, the lack of full-scale comparative studies has led to a dubiety regarding the selection of a suitable method for a specific reliability analysis problem. In this study, the performance of commonly used second-order reliability methods is assessed based on the problem scale, curvatures at the …
Accelerated Performance Degradation Of Single-Phase Cold Plates For Direct-To-Chip Liquid Cooled Data Centers, Lochan Sai Reddy Chinthaparthy
Accelerated Performance Degradation Of Single-Phase Cold Plates For Direct-To-Chip Liquid Cooled Data Centers, Lochan Sai Reddy Chinthaparthy
Mechanical and Aerospace Engineering Theses - Archive
Expanding demands for cloud-based computing and storage, the Internet of Things, and AI-based applications have escalated thermal loads in high-density data centers which necessitated the utilization of more efficient cooling technologies. Direct-to-chip liquid cooling using cold plates has proven to be one of the most efficient methods to dissipate the high heat fluxes of modern high-power CPUs and GPUs. While the published literature has well-documented research on the thermal aspects of direct liquid cooling, a detailed account of reliability degradation is missing. The present investigation provides an in-depth analysis of the reliability degradation of copper cold plates used in high-power …
Autonomous Guidance Of Unmanned Combat Air Vehicles In Basic Fighter Maneuvering, Jeffery G. Dean
Autonomous Guidance Of Unmanned Combat Air Vehicles In Basic Fighter Maneuvering, Jeffery G. Dean
Mechanical and Aerospace Engineering Dissertations - Archive
Basic fighter maneuvering, or BFM, is the dynamic engagement of two or more aircraft in close-range air combat. The relatively recent introduction of advanced unmanned combat air vehicles (UCAVs) has opened the possibility for automated systems to be players in this arena of air-to-air combat, which has thus far been limited to manned aircraft. In order to design an unmanned system that could fight and win a BFM engagement, the system must include an advanced system for guidance. This dissertation leverages techniques from gain scheduling and incorporates adjustable aimpoint guidance, in order to address the capability for UCAVs to execute …
Estimating Smart Wi-Fi Thermostat-Enabled Thermal Comfort Control Savings For Any Residence, Abdulelah D. Alhamayani, Qiancheng Sun, Kevin Hallinan
Estimating Smart Wi-Fi Thermostat-Enabled Thermal Comfort Control Savings For Any Residence, Abdulelah D. Alhamayani, Qiancheng Sun, Kevin Hallinan
Mechanical and Aerospace Engineering Faculty Publications
Nowadays, most indoor cooling control strategies are based solely on the dry-bulb temperature, which is not close to a guarantee of thermal comfort of occupants. Prior research has shown cooling energy savings from use of a thermal comfort control methodology ranging from 10 to 85%. The present research advances prior research to enable thermal comfort control in residential buildings using a smart Wi-Fi thermostat. "Fanger's Predicted Mean Vote model" is used to define thermal comfort. A machine learning model leveraging historical smart Wi-Fi thermostat data and outdoor temperature is trained to predict indoor temperature. A Long Short-Term-Memory neural network algorithm …
Computational Sodium Heat Pipe Simulation In Three Dimensions For Transient Nuclear Reactor Analysis With Variable Surface Heat Flux, Valerie Jean Lawdensky
Computational Sodium Heat Pipe Simulation In Three Dimensions For Transient Nuclear Reactor Analysis With Variable Surface Heat Flux, Valerie Jean Lawdensky
UNLV Theses, Dissertations, Professional Papers, and Capstones
Heat pipes are used to transfer heat through phase change in a liquid/vapor contained in a metal tube. They are passive devices that require no pumps to circulate the fluid and can transfer heat far more efficiently than a solid copper rod of the same diameter. They are commonly used in laptop computers where copper heat pipes filled with water take heat away from the CPU and transfer the heat to air through a heat exchanger. Heat pipes were also used in the Kilopower nuclear reactor where higher temperatures required sodium as the working fluid with stainless steel tubes. Computer …